U.S. GEOLOGICAL SURVEY DIGITAL DATA SERIES DDS-46


Geology and Resource Assessment of the Venezuelan Guayana Shield at 
1:500,000 scale--A Digital Representation of Maps published by the U.S. 
Geological Survey

By Paul G. Schruben(1), Jeffrey C. Wynn(1), Floyd Gray(2), Dennis P. Cox(3), 
John H. Stewart(3), and William E. Brooks(3)

	(1) U.S. Geological Survey 
		920 National Center
		12201 Sunrise Valley Drive
		Reston, VA  22092-9998

	(2) U.S. Geological Survey
		210 E. 7th St
		Tucson, AZ  85705-8454

	(3) Formerly with U.S. Geological Survey


U.S. DEPARTMENT OF THE INTERIOR
BRUCE BABBITT, Secretary

U.S. GEOLOGICAL SURVEY
Gordon P. Eaton, Director

For sale by U.S. Geological Survey, Map Distribution
Box 25286, Building 810, Federal Center
Denver, CO 80225

Prepared in the Eastern Region, Reston, Va.  
 Manuscript approved for publication          .

1997

TABLE OF CONTENTS

Title Page
Disclaimer
System Requirements
Acknowledgments
Contacts
Disc Contents
Project Overview
History of the Maps
Bulletin 2062 Text and Figures Files
References for this Disc
Digital Production Techniques
Map Projection
Cautions Relating to the Use of the Maps
Online Files
Graphics Formats Available on the Disc
ARCVIEW 1 and ARC/INFO Files
	Export Files
	Raw UNIX Coverages
	PC ARCVIEW 1 Coverages
	Running the Plot Programs
Installing ARCVIEW 1 
Using ARCVIEW 1
ARCVIEW 1 Files
ARCVIEW 3 Files
Coverage Data Definition
DLG Optional Format
Descripton of Map Units

DISCLAIMER

	This Compact Disc-Read Only Memory (CD-ROM) publication was prepared by an agency of the United States Government.  Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed in this report, or represents that its use would not infringe privately owned rights.  Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof.  Any views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.  
	Although all data and software published on this CD-ROM have been used by the USGS, no warranty, expressed or implied, is made by the U.S. Geological Survey as to the accuracy of the data and related materials and/or the functioning of the software. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these data, software, or related materials.  
	Graphical map depictions on this disc are intended to be used within the map scale limits applicable to the source data. Although software enables the user to show images on the disc at various scales, the user is cautioned to refer to the source documentation for the appropriate map scale limitations.





SYSTEM REQUIREMENTS 

	This CD-ROM was produced in accordance with the ISO 9660 standard and thus allows access to the disc files by computers with ISO 9660 software drivers.  The disc contains Adobe Acrobat Reader software for DOS, Macintosh, UNIX, and Windows. as well as a graphics display program, ArcView 1, for Windows 3.x.  

ARCVIEW 1 REQUIREMENTS

    80386 or better CPU
    Math coprocessor recommended
    Windows 3.0 or higher but not Windows 95
    4 Mb of RAM, 8 Mb strongly recommended
    15 Mb of disk space
    Super VGA graphics system, 256 colors, 640x480 pixels minimum, 
       1024x768 pixels strongly recommended
    Microsoft-compatible mouse
    Windows-supported printer


ARCVIEW 3 REQUIREMENTS

    80486 or better CPU
    Windows 3.x, 95, or NT
    12-16 Mb of RAM
    Super VGA graphics system, 256 colors, 640x480 pixels minimum, 
       1024x768 pixels strongly recommended
    Microsoft-compatible mouse

or

    Power Macintosh or 68040 processor with FPU
    System 7.1 or higher
    16-18 Mb of RAM 



ADOBE ACROBAT READER REQUIREMENTS:

A color display monitor is strongly recommended with all platforms.

Windows 95 - rs32e30.exe

Minimum 
     i386(TM), i486(TM), Pentium(R), or
     Pentium Pro processor-based personal computer 
     Microsoft Windows 95, or Windows NT(R) 3.51 or later 
     8 MB of RAM (16 MB for Windows NT) for Acrobat Reader 
     10 MB of available hard-disk space

Recommended 
     Pentium processor-based personal computer 
     Windows 95 or Windows NT 
     16 MB of RAM (24 for Windows NT) 
     10 MB of available hard-disk space 


Windows NT - rs32e30.exe

Minimum 
     i386(TM), i486(TM), Pentium(R), or Pentium Pro processor
     Windows NT(R) 3.51 or later 
     8 MB of RAM (16 MB for Windows NT) for Acrobat Reader 
     10 MB of available hard-disk space 

Recommended
     Pentium processor-based personal
     computer 
     Windows 95 or Windows NT 
     16 MB of RAM (24 for Windows NT) 
     10 MB of available hard-disk space 


Windows 3.1 and 3.11 for Workgroups  - rs16e30.exe

Minimum 
     i386(TM), i486(TM), Pentium(R), or Pentium Pro processor
     Microsoft Windows 3.1 or Windows 3.11 or later 
     8 MB of RAM for Acrobat Reader
     5 MB of available hard-disk space

Recommended 
     Pentium processor-based personal computer 
     Microsoft Windows 3.1 or Windows 3.11 or later 
     12 MB of available hard-disk space 



Macintosh and Power Macintosh - Install Acrobat Reader 3.0, Search Installer

Minimum 
     Macintosh with a 68020 or greater processor, or Power Macintosh 
     3.5 MB of RAM (5 MB for Power Macintosh) available to Acrobat Reader 
     Apple(R) System Software version 7.1 or later 

Recommended 
     8 MB of available RAM 
     Apple System Software version 7.1.2 or later 
     12.5 MB of available hard-disk space


UNIX

UNIX system requirements 
     12 MB of disk space for Acrobat Reader 
     System with 32 MB of RAM 

Sun SPARCstation(R) - acroread_sunos_30.tar.gz, acroread_solaris_30.tar.gz
     SunOS 4.1.3 or 4.1.4 or Solaris 2.3, 2.4, or 2.5 
     OpenWindows(TM) (version 3.0 or later),
     Motif(TM) window manager (1.2.3 or later),
     OpenLook version 3.0, or 
     Common Desktop Environment (CDE) 1.0 and above 

HP Series 9000 workstation, model 700 or greater - acroread_hpux_30.tar.gz
     HP-UX 9.0.3 or later 
     X Window System(TM) X11R5 with HP-VUE or CDE 1.0 
     12 megabytes of available hard disk space 
     A 32 megabyte machine 

IBM(R) RS/6000(TM) workstation - acroread_aix_30.tar.gz
     AIX 4.1 or later operating system 
     Common Desktop Environment (CDE) or the Motif window manager 

Silicon Graphics workstation - acroread_irix_30.tar.gz
     IRIX(TM) 5.3 or later operating system software 
     12 megabytes of available hard disk space 
     A 32 megabyte machine 

Linux workstation - acroread_linux_30.tar.gz
     LINUX 5.3 or later operating system software
     12 megabytes of available hard disk space 
     A 32 megabyte machine



OS/2 - aro2e30.exe

Minimum 
     i386, i486, Pentium, or Pentium Pro processor
     IBM OS/2 Warp or Warp Connect 3.0 or later 
     4 MB application RAM available to Acrobat Reader 
     8 MB RAM for system 
     5 MB hard-disk space, plus 5 MB temporary space for installation 

 Recommended 
      Pentium processor
      IBM OS/2 Warp 4.0 


Adobe Acrobat Reader 1.0 for DOS - rdrdos10.zip

Minimum 
     i386(TM), i486(TM) processor
     Microsoft DOS 3.3 or later 
     2 MB of RAM for Acrobat Reader. 
     5 MB of available hard-disk space

Recommended 
     486 or Pentium processor
     Microsoft DOS 3.3 or later 
     4 MB of application RAM 
     5 MB of available hard-disk space 





ACKNOWLEDGEMENTS

	Development of the graphics files on this CD-ROM spanned many years and involved the efforts of many organizations and individuals.  Most of the digitizing was done in GSMAP by Jeff Wynn (USGS) and others.  The northern quadrangles were scanned from tracings created by the geologists.  Thanks to the following authors for those materials:

John H. Stewart (USGS)
Dennis P. Cox (USGS)
Floyd Gray (USGS)
W. E. Brooks (USGS) 

	Thanks to Corporaci—n Venezolana de Guayana, TŽcnica Minera C.A. and the following authors of Venezuela maps and reports for their help in the preparation of the digital files:

Juan Acosta
Jesśs Aresp—n
Yasmin Estanga
Luis Franco
AndrŽs Garc’a
Yolanda Lopez
Elis Lugo
Iris Marcano
FŽlix Mart’nez
Vicente Mendoza-S.
Stephen D. Olmore
InŽs Rend—n
HaydŽe Rinc—n
Nelson Rivero
Edixon Salazar
Gary B. Sidder (formerly USGS, now Golden Star Resources)
Frank Tovar


	Thanks to David K. Traudt, USGS, who assembled the files and directories from tape to master CD-ROM.  Thanks to the following personnel in the USGS who provided disk files of Bulletin 2062 text and figures as well as many thoughtful suggestions for improvements to the maps and text on the CD-ROM.

Frederick C. Brunstein
David A. Emery
Will Stettner
Judith W. Stoeser


CONTACTS

Questions about the digital map files should be directed to:

Paul Schruben	Telephone     (703) 648-6142
	FAX                (703) 648-6383
	E-mail            pschrube@usgs.gov

U.S. Geological Survey, 954 National Center, Reston, VA  22092-9998.

Technical help with ArcView 1 is available via CompuServe by typing GO ESRI.

Copies of the original USGS 1993 Bulletin 2062, MF maps cited in the Documentation of Map Units, and this CD-ROM are available from:

	U.S. Geological Survey, Map Distribution
	Box 25286, Building 810
	Federal Center
	Denver, CO 80225

Tel: (888) ASK-USGS or  for overseas access  (703) 648-6045.



DISC CONTENTS

1readme.doc       description of this disc, Microsoft Word 6 file
1readme.mac.text  description of this disc, Macintosh/OS plain text file
1readme.pdf       description of this disc, Adobe Acrobat Reader file
1readmet.dos      description of this disc, MS/DOS plain text file
1readmew.dos      description of this disc, Microsoft Word for Windows 1.0
acrobat       directory containing Acrobat Reader installer programs
arcview1      directory containing ArcView 1 installer program 
arcpc         directory containing PC ArcView 1 and ARC/INFO directories.  
                Same as arcunix6 directory below
arcunix6      directory containing ArcView 1 and ARC/INFO 6.1.2 directories
  at            directory containing files for Atabapo 2ˇx3ˇ quadrangle 
                  (Venezuela part)
    at.aml        ARC/PLOT program for 44" Versatec plotter
    at.av         ArcView 1 file
    at.gra        ARC/PLOT plot file for 44" Versatec plotter
    atanno5       geographic place name annotation
    atcor         correlation of map units
    atft          faults
    atge          geology
    atlab         rock unit label annotation
    atleg         map legend
    atma          buried magnetic bodies
    atout         quadrangle outline and lat/long numbers
    atpl          political boundaries
    atscale       1:500,000 scale bar, title, & citation
    atst          single-line tributaries
    attc          latitude/longitude tics for this quadrangle
    grid          lat/long grid lines for index map
    index         index map showing quadrangle names and surrounding 
                    countries
    vztc          latitude/longitude numbers and tics for index map
  ay          directory containing Puerto Ayacucho 2ˇx3ˇ quadrangle 
                    (Venezuela part) files
    ay.aml        ARC/PLOT program for 44" Versatec plotter
    ay.av         ArcView 1 file
    ay.gra        ARC/PLOT plot file for 44" Versatec plotter
    ayanno5       geographic place name annotation
    aycor         correlation of map units
    aycrlbm       crossection geology rock unit labels
    aycrm         crossection geology polygons
    ayft          faults
    ayge          geology
    aylab         rock unit label annotation
    aylabcr       crossection line and annotation on map
    ayleg         map legend
    aylegpt       map legend points
    ayma          buried magnetic bodies
    aymalab       buried magnetic bodies
    ayout         quadrangle outline and lat/long numbers
    aypl          political boundaries
    ayrd          roads
    ayscale       1:500,000 scale bar, title, & citation
    ayst          single-line tributaries
    aytc          latitude/longitude tics for this quadrangle
    grid          lat/long grid lines for index map
    index         index map showing quadrangle names and surrounding 
                    countries
    vztc          latitude/longitude numbers and tics for index map
  ca          directory containing R’o Caura 2ˇ by 3ˇ quadrangle files
    ca.aml        ARC/PLOT program for 44" Versatec plotter
    ca.av         ArcView 1 file
    ca.gra        ARC/PLOT plot file for 44" Versatec plotter
    caanno5       geographic place name annotation
    cacor         correlation of map units
    caft          faults
    cage          geology
    calab         rock unit label annotation
    caleg         map legend
    calegpt       map legend points
    cama          buried magnetic bodies
    caout         quadrangle outline and lat/long numbers
    capl          political boundaries
    cascale       1:500,000 scale bar, title, & citation
    cast          single-line tributaries
    catc          latitude/longitude tics for this quadrangle
    grid          lat/long grid lines for index map
    index         index map showing quadrangle names and surrounding 
                    countries
    vztc          latitude/longitude numbers and tics for index map
  es          directory containing La Esmeralda 2ˇx3ˇ quadrangle 
                    (Venezuela part) files
    es.aml        ARC/PLOT program for 44" Versatec plotter
    es.av         ArcView 1 file
    es.gra        ARC/PLOT plot file for 44" Versatec plotter
    esanno5       geographic place name annotation
    escor         correlation of map units
    esft          faults
    esge          geology
    eslab         rock unit label annotation
    esleg         map legend
    eslegpt       map legend points
    esma          buried magnetic bodies
    esout         quadrangle outline and lat/long numbers
    espl          political boundaries
    esscale       1:500,000 scale bar, title, & citation
    esst          single-line tributaries
    estc          latitude/longitude tics for this quadrangle
    grid          lat/long grid lines for index map
    index         index map showing quadrangle names and surrounding 
                    countries
    vztc          latitude/longitude numbers and tics for index map
  gu          directory containing Guri and southern part of the Tucupita 
                    2ˇx3ˇ quadrangles files
    grid          lat/long grid lines for index map
    gu.aml        ARC/PLOT program for 44" Versatec plotter
    gu.av         ArcView 1 file
    gu.gra        ARC/PLOT plot file for 44" Versatec plotter
    guanno5       geographic place name annotation
    gucor         correlation of map units
    guft          faults
    guge          geology
    gulab         rock unit label annotation
    guleg         map legend
    gulegpt       map legend points
    guout         quadrangle outline and lat/long numbers
    gupl          political boundaries
    gurd          roads
    guscale       1:500,000 scale bar, title, & citation
    gust          single-line tributaries
    gutc          latitude/longitude tics for this quadrangle
    index         index map showing quadrangle names and surrounding 
                    countries
    vztc          latitude/longitude numbers and tics for index map
  ma          directory containing R’o Mavaca 2ˇx3ˇ quadrangle (Venezuela 
                    part)
    grid          lat/long grid lines for index map
    index         index map showing quadrangle names and surrounding 
                    countries
    ma.aml        ARC/PLOT program for 44" Versatec plotter
    ma.av         ArcView 1 file
    ma.gra        ARC/PLOT plot file for 44" Versatec plotter
    maanno5       geographic place name annotation
    macor         correlation of map units
    maft          faults
    mage          geology
    malab         rock unit label annotation
    maleg         map legend
    mama          buried magnetic bodies
    maout         quadrangle outline and lat/long numbers
    mascale       1:500,000 scale bar, title, & citation
    mast          single-line tributaries
    matc          latitude/longitude tics for this quadrangle
    vztc          latitude/longitude numbers and tics for index map
  pc          directory containing Piedra de Cocuy 2ˇx3ˇ quadrangle 
                    (Venezuela part) files
    grid          lat/long grid lines for index map
    index         index map showing quadrangle names and surrounding 
                    countries
    pc.aml        ARC/PLOT program for 44" Versatec plotter
    pc.av         ArcView 1 file
    pc.gra        ARC/PLOT plot file for 44" Versatec plotter
    pcanno5       geographic place name annotation
    pccor         correlation of map units
    pcft          faults
    pcge          geology
    pclab         rock unit label annotation
    pcleg         map legend
    pclegpt       map legend points
    pcma          buried magnetic bodies
    pcout         quadrangle outline and lat/long numbers
    pcpl          political boundaries
    pcscale       1:500,000 scale bar, title, & citation
    pcst          single-line tributaries
    pctc          latitude/longitude tics for this quadrangle
    vztc          latitude/longitude numbers and tics for index map
  pi          directory containing Ciudad Piar and part of the Ciudad 
                    Bolivar 2ˇx3ˇ quadrangles files
    fnt040        ARC/INFO font file necessary for sag fault line symbol
    grid          lat/long grid lines for index map
    index         index map showing quadrangle names and surrounding 
                    countries
    pi.aml        ARC/PLOT program for 44" Versatec plotter
    pi.av         ArcView 1 file
    pi.gra        ARC/PLOT plot file for 44" Versatec plotter
    pianno5       geographic place name annotation
    picor         correlation of map units
    pift          faults
    pige          geology
    pilab         rock unit label annotation
    pileg         map legend
    pilegpt       map legend points
    pima          kimberlite area
    piout         quadrangle outline and lat/long numbers
    pipl          political boundaries
    pird          roads
    piscale       1:500,000 scale bar, title, & citation
    pisr          structural lines from SLAR
    pist          single-line tributaries
    pitc          latitude/longitude tics for this quadrangle
    vztc          latitude/longitude numbers and tics for index map
  se          directory containing Santa Elena 2ˇx3ˇ quadrangle (Venezuela 
                    part) files
    grid          lat/long grid lines for index map
    index         index map showing quadrangle names and surrounding 
                    countries
    se.aml        ARC/PLOT program for 44" Versatec plotter
    se.av         ArcView 1 file
    se.gra        ARC/PLOT plot file for 44" Versatec plotter
    seanno5       geographic place name annotation
    secor         correlation of map units
    seft          faults
    sege          geology
    selab         rock unit label annotation
    seleg         map legend
    selegpt       map legend points
    seout         quadrangle outline and lat/long numbers
    sepl          political boundaries
    serd          roads
    sescale       1:500,000 scale bar, title, & citation
    sest          single-line tributaries
    setc          latitude/longitude tics for this quadrangle
    vztc          latitude/longitude numbers and tics for index map
  sf          directory containing San Fernando de Apure 2ˇx3ˇ quadrangle 
                    (Bolivar part) files
    grid          lat/long grid lines for index map
    index         index map showing quadrangle names and surrounding 
                    countries
    sf.aml        ARC/PLOT program for 44" Versatec plotter
    sf.av         ArcView 1 file
    sf.gra        ARC/PLOT plot file for 44" Versatec plotter
    sfanno5       geographic place name annotation
    sfcor         correlation of map units
    sfft          faults
    sfge          geology
    sflab         rock unit label annotation
    sfleg         map legend
    sflegpt       map legend points
    sfout         quadrangle outline and lat/long numbers for ArcView
    sfpl          political boundaries
    sfscale       1:500,000 scale bar, title, & citation
    sfst          single-line tributaries
    sftc          latitude/longitude tics for this quadrangle 
    vztc          latitude/longitude numbers and tics for index map
  vz          directory containing combined map coverages for Venezuelan 
                    Guayana Shield, all quadrangles
    av.mrk        ArcView markerset to be copied to the ARCHOME directory
    av.txt        ArcView textset to be copied to the ARCHOME directory
    deposit       mineral deposits, prospects and occurrences
    equi2geo.prj  projection file for converting equidistant conic to 
                    decimal degrees
    fnt040        ARC/INFO font file necessary for sag fault line symbol
    ge.ai         Illustrator 6.0 version of ge.eps
    ge.eps        ARC/PLOT Postscript plot file for 44" Versatec plotter
    ge.gra        ARC/PLOT plot file for 44" Versatec plotter
    geo2equi.prj  projection file for converting decimal degrees to 
                    equidistant conic
    grid          lat/long grid lines for index map
    index         index map showing quadrangle names and surrounding 
                    countries
    mrdsek.mrk    ARC/PLOT markerset for other point symbols
    myalcgeol.mrk ARC/PLOT markerset for cities, bedding, joint symbols
    myplotter.shd ARC/PLOT shadeset for geology patterns
    myplt.lin     ARC/PLOT lineset for faults, roads, political boundaries
    places        geographic place names
    ra            mineral resource permissive areas map A
    raanno        mineral resource permissive areas map A annotation
    rb            mineral resource permissive areas map B
    rbanno        mineral resource permissive areas map B annotation
    rbstruct      mineral resource permissive areas map B structural 
                    features
    scale         scalebar and projection information
    vz.aml        ARC/PLOT program for 44" Versatec plotter
    vz.av         ArcView 1 view file
    vz.apr        ArcView 3 project file
    vzcor         correlation of map units
    vzctry        Northeast South America country borders
    vzft          faults, annotation, joints, and bedding
    vzge          geology
    vzlab         rock unit annotation and leaders
    vzma          buried magnetic bodies
    vzout         outer edge of combined quadrangles in study area 
    vzpl          study area political boundaries
    vzprov        Venezuela province boundaries for index map
    vzrd          roads
    vzst          single-line tributaries and annotation
    vztc          latitude/longitude numbers and tics for index map
arcunix7        directory containing ArcView 3 and ARC/INFO 7 directory
  vz              directory containing combined map coverages for Venezuelan 
                    Guayana Shield, all quadrangles.  Same as in 
                    arcunix6/vz.
bull2062        directory containing text and figures from Bulletin 2062
  doc
    tables.doc      Word 5.1           tables 1-2, 4-11
    tabside.doc     Word 5.1           table 3
  mif
    b2062con.mif    framemaker 3.0p1b  table of contents
    b2062fnt.mif    framemaker 3.0p1b  cover 1, cover 2, i, ii, iii
    b2062txt.mif    framemaker 3.0p1b  main body, p. 1-120
  rtf
    b2062con.rtf    rich text (RTF)    table of contents
    b2062txt.rtf    rich text (RTF)    main body, p. 3-5
  tif
    vzget.tif       TIF                Plate 2, geology, key part
    vzge.tif        TIF                Plate 2, geologic map part 
    vzmin.tif       TIF                Plate 6, mineral deposits
  txt
    b2062con.txt    text               table of contents
    b2062fnt.txt    text               i, ii
    b2062txt.txt    text               main body, p. 1-72
dlg             directory containing Digital Line Graph (DLG) Optional files
  cor.dlg       correlation of map units in Equidistant Conic projection
  cordd.dlg     correlation of map units in decimal degrees
  ft.dlg        faults in Equidistant Conic projection
  ftdd.dlg      faults in decimal degrees
  ge.dlg        geology in Equidistant Conic projection
  gedd.dlg      geology in decimal degrees
  ptype.unl     rock unit names, descriptions, colors for Versatec 
                  plotter
  scale.dlg     scale bar in Equidistant Conic projection
  scaledd.dlg   scale bar in decimal degrees
  vzline.unl    fault and contact line types
export        directory containing directories of ARC/INFO export files and 
                programs
  at          directory containing Atabapo quadrangle files
    at.aml        ARC/PLOT program for 44" Versatec plotter
    at.av         ArcView 1 file
    at.gra        ARC/PLOT 1040 plot file for 44" Versatec plotter.  
                    This a binary file
    atanno5.e00   geographic place name annotation
    atcor.e00     correlation of map units
    atft.e00      faults
    atge.e00      geology
    atlab.e00     rock unit label annotation
    atleg.e00     map legend
    atma.e00      buried magnetic bodies
    atout.e00     quadrangle outline and lat/long numbers
    atpl.e00      political boundaries
    atscale.e00   1:500,000 scale bar, title, & citation
    atst.e00      single-line tributaries
    attc.e00      latitude longitude tics for this quadrangle
    grid.e00      lat/long grid lines for index map
    import.aml    ARC program for importing coverage
    index.e0*     index map showing quadrangle names and surrounding 
                    countries, files 0-1
    vztc.e00      latitude longitude tics for index map
  ay          directory containing Puerto Ayacucho quadrangle files
    ay.aml        ARC/PLOT program for 44" Versatec plotter
    ay.av         ArcView 1 file
    ay.gra        ARC/PLOT 1040 plot file for 44" Versatec plotter.  
                    This a binary file
    ayanno5.e00   geographic place name annotation
    aycor.e00     correlation of map units
    aycrlbm.e00   cross section labels
    aycrm.e00     cross section arcs
    ayft.e00      faults
    ayge.e00      geology
    aylab.e00     rock unit label annotation
    aylabcr.e00   rock unit label annotation for cross section
    ayleg.e00     map legend
    aylegpt.e00   map legend points
    ayma.e00      buried magnetic bodies
    aymalab.e00   buried magnetic bodies labels
    ayout.e00     quadrangle outline and lat/long numbers
    aypl.e00      political boundaries
    ayrd.e00      roads
    ayscale.e00   1:500,000 scale bar, title, & citation
    ayst.e00      single-line tributaries
    aytc.e00      latitude longitude tics for this quadrangle
    grid.e00      lat/long grid lines for index map
    import.aml    ARC program for importing coverage
    index.e0*     index map showing quadrangle names and surrounding 
                    countries, files 0-1
    vztc.e00      latitude longitude tics for index map
  ca          directory containing R’o Caura quadrangle files
    ca.aml        ARC/PLOT program for 44" Versatec plotter
    ca.av         ArcView 1 file
    ca.gra        ARC/PLOT 1040 plot file for 44" Versatec plotter.  
                    This a binary file
    caanno5.e00   geographic place name annotation
    cacor.e00     correlation of map units
    caft.e00      faults
    cage.e00      geology
    calab.e00     rock unit label annotation
    caleg.e00     map legend
    calegpt.e00   map legend points
    cama.e00      buried magnetic bodies
    caout.e00     quadrangle outline and lat/long numbers
    capl.e00      political boundaries
    cascale.e00   1:500,000 scale bar, title, & citation
    cast.e00      single-line tributaries
    catc.e00      latitude longitude tics for this quadrangle
    grid.e00      lat/long grid lines for index map
    import.aml    ARC program for importing coverage
    index.e0*     index map showing quadrangle names and surrounding 
                    countries, files 0-1
    vztc.e00      latitude longitude tics for index map
  es          directory containing La Esmeralda quadrangle files
    es.aml        ARC/PLOT program for 44" Versatec plotter
    es.av         ArcView 1 file
    es.gra        ARC/PLOT 1040 plot file for 44" Versatec plotter.  
                    This a binary file
    esanno5.e00   geographic place name annotation
    escor.e00     correlation of map units
    esft.e00      faults
    esge.e00      geology
    eslab.e00     rock unit label annotation
    esleg.e00     map legend
    eslegpt.e00   map legend points
    esma.e00      buried magnetic bodies
    esout.e00     quadrangle outline and lat/long numbers
    espl.e00      political boundaries
    esscale.e00   1:500,000 scale bar, title, & citation
    esst.e00      single-line tributaries
    estc.e00      latitude longitude tics for this quadrangle
    grid.e00      lat/long grid lines for index map
    import.aml    ARC program for importing coverage
    index.e0*     index map showing quadrangle names and surrounding 
                    countries, files 0-1
    vztc.e00      latitude longitude tics for index map
  gu          directory containing Guri and Tucupita quadrangle files
    grid.e00      lat/long grid lines for index map
    gu.aml        ARC/PLOT program for 44" Versatec plotter
    gu.av         ArcView 1 file
    gu.gra        ARC/PLOT 1040 plot file for 44" Versatec plotter.  
                    This a binary file
    guanno5.e00   geographic place name annotation
    gucor.e00     correlation of map units
    guft.e00      faults
    guge.e0*      geology files, 0-2
    gulab.e00     rock unit label annotation
    guleg.e00     map legend
    gulegpt.e00   map legend points
    guout.e00     quadrangle outline and lat/long numbers
    gupl.e00      political boundaries
    gurd.e00      roads
    guscale.e00   1:500,000 scale bar, title, & citation
    gust.e00      single-line tributaries
    gutc.e00      latitude longitude tics for this quadrangle
    import.aml    ARC program for importing coverage
    index.e0*     index map showing quadrangle names and surrounding 
                    countries, files 0-1
    vztc.e00      latitude longitude tics for index map
  ma          directory containing R’o Mavaca quadrangle files
    grid.e00      lat/long grid lines for index map
    import.aml    ARC program for importing coverage
    index.e0*     index map showing quadrangle names and surrounding 
                    countries, files 0-1
    ma.aml        ARC/PLOT program for 44" Versatec plotter
    ma.av         ArcView 1 file
    ma.gra        ARC/PLOT 1040 plot file for 44" Versatec plotter.  
                    This a binary file
    maanno5.e00   geographic place name annotation
    macor.e00     correlation of map units
    maft.e00      faults
    mage.e00      geology
    malab.e00     rock unit label annotation
    maleg.e00     map legend
    mama.e00      buried magnetic bodies
    maout.e00     quadrangle outline and lat/long numbers
    mascale.e00   1:500,000 scale bar, title, & citation
    mast.e00      single-line tributaries
    matc.e00      latitude longitude tics for this quadrangle
    vztc.e00      latitude longitude tics for index map
  pc          directory containing Piedra de Cocuy quadrangle files
    grid.e00      lat/long grid lines for index map
    import.aml    ARC program for importing coverage
    index.e0*     index map showing quadrangle names and surrounding 
                    countries, files 0-1
    pc.aml        ARC/PLOT program for 44" Versatec plotter
    pc.av         ArcView 1 file
    pc.gra        ARC/PLOT 1040 plot file for 44" Versatec plotter.  
                    This a binary file
    pcanno5.e00   geographic place name annotation
    pccor.e00     correlation of map units
    pcft.e00      faults
    pcge.e00      geology
    pclab.e00     rock unit label annotation
    pcleg.e00     map legend
    pclegpt.e00   map legend points
    pcma.e00      buried magnetic bodies
    pcout.e00     quadrangle outline and lat/long numbers
    pcpl.e00      political boundaries
    pcscale.e00   1:500,000 scale bar, title, & citation
    pcst.e00      single-line tributaries
    pctc.e00      latitude longitude tics for this quadrangle
    vztc.e00      latitude longitude tics for index map
  pi          directory containing Ciudad Piar and Ciudad Bolivar 
                  quadrangle files
    fnt040        ARC/INFO font file necessary for sag fault line symbol
    grid.e00      lat/long grid lines for index map
    import.aml    ARC program for importing coverage
    index.e0*     index map showing quadrangle names and surrounding 
                    countries, files 0-1
    pi.aml        ARC/PLOT program for 44" Versatec plotter
    pi.av         ArcView 1 file
    pi.gra        ARC/PLOT 1040 plot file for 44" Versatec plotter.  
                    This a binary file.
    pianno5.e00   geographic place name annotation
    picor.e00     correlation of map units
    pift.e00      faults
    pige.e0*      geology, 0-2
    pilab.e00     rock unit label annotation
    pileg.e00     map legend
    pilegpt.e00   map legend points
    pima.e00      buried magnetic bodies
    piout.e00     quadrangle outline and lat/long numbers
    pipl.e00      political boundaries
    pird.e00      roads
    piscale.e00   1:500,000 scale bar, title, & citation
    pisr.e00      structural lines from SLAR
    pist.e00      single-line tributaries
    pitc.e00      latitude longitude tics for this quadrangle
    vztc.e00      latitude longitude tics for index map
  se          directory containing Santa Elena quadrangle files
    grid.e00      lat/long grid lines for index map
    import.aml    ARC program for importing coverage
    index.e0*     index map showing quadrangle names and surrounding 
                    countries, files 0-1
    se.aml        ARC/PLOT program for 44" Versatec plotter
    se.av         ArcView 1 file
    se.gra        ARC/PLOT 1040 plot file for 44" Versatec plotter.  
                    This a binary file
    seanno5.e00   geographic place name annotation
    secor.e00     correlation of map units
    seft.e00      faults
    sege.e0*      geology, 0-1
    selab.e00     rock unit label annotation
    seleg.e00     map legend
    selegpt.e00   map legend points
    seout.e00     quadrangle outline and lat/long numbers
    sepl.e00      political boundaries
    serd.e00      roads
    sescale.e00   1:500,000 scale bar, title, & citation
    sest.e00      single-line tributaries
    setc.e00      latitude longitude tics for this quadrangle
    vztc.e00      latitude longitude tics for index map
  sf          directory containing San Fernando quadrangle files
    grid.e00      lat/long grid lines for index map
    import.aml    ARC program for importing coverage
    index.e0*     index map showing quadrangle names and surrounding 
                    countries, files 0-1
    sf.aml        ARC/PLOT program for 44" Versatec plotter
    sf.av         ArcView 1 file
    sf.gra        ARC/PLOT 1040 plot file for 44" Versatec plotter.  
                    This a binary file
    sfanno5.e00   geographic place name annotation
    sfcor.e00     correlation of map units
    sfft.e00      faults
    sfge.e00      geology
    sflab.e00     rock unit label annotation
    sfleg.e00     map legend
    sflegpt.e00   map legend points
    sfout.e00     quadrangle outline and lat/long numbers
    sfpl.e00      political boundaries
    sfscale.e00   1:500,000 scale bar, title, & citation
    sfst.e00      single-line tributaries
    sftc.e00      latitude longitude tics for this quadrangle
    vztc.e00      latitude longitude tics for index map
  vz          directory containing export files for combined coverages
    avmrk.e00     ArcView markerset to be copied to the ARC HOME directory
    avtxt.e00     ArcView textset to be copied to the ARC HOME directory
    deposit.e0*   mineral deposits, prospects and occurrences, files 0-2
    equi2geo.prj  projection file for converting equidistant conic to 
                    decimal degrees
    fnt040        ARC/INFO font file necessary for sag fault line symbol
    ge.gra        ARC/PLOT 1040 plot file for 44" Versatec plotter.  
                    This a binary file
    geo2equi.prj  projection file for converting decimal degrees to 
                    equidistant conic
    grid.e00      lat/long grid lines for index map
    import.aml    ARC script for importing all coverages
    index.e0*     index map showing quadrangle names and surrounding 
                    countries, files 0-1
    mrdsek.e00    ARC/PLOT markerset for other point symbols
    myalcgeol.e00 ARC/PLOT markerset for cities, bedding, joint symbols
    myplotter.e00 ARC/PLOT shadeset for geology patterns
    myplt.e00     ARC/PLOT lineset for faults, roads, political boundaries
    places.e00    geographic place names
    ptpat.e00     geology polygon lookup table, plotter patterns
    ptpl.e00      point symbol lookup table
    ptype.e00     geology polygon lookup table, Versatec colors
    ra.e0*        mineral resource permissive areas map A
    raanno.e00    mineral resource permissive areas map A annotation
    rb.e0*        mineral resource permissive areas map B files, 0-1
    rbanno.e00    mineral resource permissive areas map B annotation
    rbstruct.e00  mineral resource permissive areas map B structural 
                    features
    scale.e00     scalebar and projection information
    vz.aml        ARC/PLOT program for 44" Versatec plotter
    vz.av         ArcView 1 view file
    vz.apr        ArcView 3 project file
    vzcor.e00     correlation of map units
    vzctry.e0*    Northeast South America country borders, 0-1
    vzft.e00      faults, annotation, joints and bedding
    vzge.e00      geology files, 0-9
    vzlab.e0*     rock unit annotation and leaders files, 0-2
    vzline.e00    lineset for Arc/Edit, Arc/Plot, Versatec plots
    vzma.e00      buried magnetic bodies
    vzout.e00     outer edge of combined quadrangles in study area 
    vzpl.e00      study area political boundaries
    vzprov.e00    Venezuela province boundaries for index map
    vzrd.e00      roads
    vzst.e0*      single-line tributaries and annotation files, 0-2
    vztc.e00      latitude/longitude numbers and tics for index map


PROJECT OVERVIEW

	Conversion of the Venezuela maps to a computerized digital format was undertaken for the following reasons:

1) The digital format facilitates the presentation and analysis of earth-science data.  Digital maps can be displayed at any scale or projection, whereas a paper map has a fixed scale and projection.  However, the maps on this disc are not intended to be used at any scale more detailed than 1:500,000.
	A geographic information system (GIS) allows combining and overlaying of layers for analysis of spatial relations not readily apparent in the standard paper publication.  Digital data on geology, geophysics, and geochemistry can be combined to create useful derivative products.

2) The digital format was used to facilitate publication in both paper and electronic form.  For the R’o Caura paper map publication (Brooks and others, 1995), digital images were sent to the Gerber plotter, a vector-to-film processor.  The other 1:500,000-scale MF maps were reproduced photographically from electrostatic plotter output on clear mylar.  The published digital formats include this CD-ROM and ARC/INFO Export files to be located on the World Wide Web on the Internet.





HISTORY OF THE MAPS

	The data in this CD-ROM are based on a mineral resource assessment of the Venezuelan Guayana Shield, conducted between 1987 and 1991 by the U.S. Geological Survey and Corporaci—n Venezolana de Guayana, TŽcnica Minera, (USGS, 1993).  The Venezuelan Shield occupies about 415,000 sq km in the south and east part of Venezuela.  The study area is bounded on the north by the R’o Orinoco.  It includes all of the Territorio Federal Amazonas, Estado Bol’var, and part of Estado Delta Amacuro.  The original resource assessment publication USGS Bulletin 2062 consists of 121 pages of text and figures as well as eight full-color maps:

	  Geographic
	  Geologic and tectonic
	  Bouguer gravity
	  Two mineral-occurrence maps
	  Side-looking airborne radar image
	  Two permissive domain maps

	The side-looking airborne radar image and the Bouguer gravity map are not included in this CD-ROM.  The geology layer from the 1993 Bulletin was revised and published as a series of MF and I maps:

   Quadrangles        Map                Authors
--------------------------------------------------------------------
   Guri + Tucupita    MF-2242            Cox and others, 1993
   Ciudad Piar +      MF-2246            Stewart and others, 1994
     Ciudad Bolivar
   San Fernando de    MF-2247            Stewart, 1994
     Apure
   Santa Elena        unpublished data   Floyd Gray and others, 1995
   R’o Caura          I-2537             Brooks and others, 1995
   Puerto Ayacucho    MF-2245            Wynn and others, 1994
   La Esmeralda       MF-2244            Wynn and others, 1994
   Atabapo            MF-2240            Wynn and others, 1994
   R’o Mavaca         MF-2241            Wynn and others, 1994
   Piedra de Cocuy    MF-2243            Wynn and others, 1994


	The digital map files on this CD-ROM were used to create the above publications.  They subsequently underwent minor revisions to reconcile conflicting rock unit names and to view correctly in ArcView.  





USGS BULLETIN 2062 TEXT AND FIGURES FILES

	The text of the 1993 USGS Bulletin 2062 is available in several Framemaker, Rich Text Word, and TIF files on the CD-ROM.  The text in the following files may vary slightly from the final publication.  Some of the files listed below duplicate parts of each other but in different formats.  The tif files were created by scanning the published Plates 2 and 6.  Plate 2 is split into two files.  The other Plates have not been scanned.

              size
file name      Kb    format             content

b2062con.mif   154   framemaker 3.0p1b  table of contents
b2062con.txt   7.6   text               table of contents
b2062con.rtf    16   rich text (RTF)    table of contents
b2062fnt.mif   134   framemaker 3.0p1b  cover 1, cover 2, i, ii, iii
b2062fnt.txt   3.4   text               i, ii
b2062txt.mif  1208   framemaker 3.0p1b  main body, p. 1-120
b2062txt.txt   251   text               main body, p. 1-72
b2062txt.rtf   9.6   rich text (RTF)    main body, p. 3-5
tables.doc     113   Word 5.1           tables 1-2, 4-11
tabside.doc    183   Word 5.1           table 3
vzge.tif     93000   TIF                Plate 2, geologic map part
vzget.tif    20000   TIF                Plate 2, geology, key part
vzmin.tif    87000   TIF                Plate 6, mineral deposits





REFERENCES FOR THIS DISC

Bellizzia-G., Alirio, Pimentel-M., Nelly, and Bajo-O., R., 1976, Mapa geol—gico estructural de Venezuela: Ministerio de Minas e Hidrocarburos, Direcci—n Geol—gica, Caracas, Venezuela, scale 1:500,000. 

Brice–o, H.O., 1982, Application of remote sensing to diamond placer exploration in a tropical jungle environment, Caron’ River, Venezuela: Golden, Colo., Colorado School of Mines, Ph.D dissertation, 176 p.

Brooks, W.E., Sidder, G.B., Wynn, J.C., Cox, D.P., Stewart, J.H., and Schruben, P.G., 1995, Geologic map of the R’o Caura 2ˇ by 3ˇ quadrangle, estado Bolivar, Venezuela: U.S. Geological Survey Miscellaneous Investigations Map I-2537.

Brooks, W.E., Tosdal, R.M., and Nu–ez, F., in press, Gold resources of the R’o Chivao study area, Estado Bol’var, Venezuela, in Sidder, G.B., Garc’a G., AndrŽs, and Stoeser, J.W., eds., Geology and mineral deposits of the Venezuelan Guayana Shield: U.S. Geological Survey Bulletin 2124.

Cox, D.P., Gray, Floyd, Acosta, Juan, Stewart, J.H., Aresp—n, Jesśs, Brooks, W.E., Franco, Luis, Salazar, Edixon, and Lopez, Yolanda, 1993, Geologic map of the Guri and southern part of the Tucupita 2ˇx3ˇ quadrangles, Bolivar State, Venezuela: U.S. Geological Survey Miscellaneous Field Studies Map MF-2242, scale 1:500,000.

Environmental Systems Research Institute, Inc., 1990, ARC/INFO 5.0 User Manuals: Redlands, Calif.

Environmental Systems Research Institute, Inc., 1992, ArcView User's Guide: Redlands, Calif.

Gaudette, H.E., Mendoza, Vicente, Hurley, P.M., and Fairbairn, H.W., 1978, Geology and age of the Parguaza rapakivi granite, Venezuela: Geological Society of America Bulletin, v. 89, p. 1335-1340.  

Gaudette, H.E., and Olszewski, W.J., Jr., 1985, Geochronology of the basement rocks, Amazonas Territory, Venezuela and the tectonic evolution of the western Guiana Shield:  Geologie en Mijnbouw, v. 64, p. 131-143.

Ghosh, S.K., 1985, Geology of the Roraima Group and its implications: Simposium Amazonico, 1st, Caracas, 1981; Ministerio de Energ’a y Minas, Direcci—n de Geolog’a Bolet’n de Geolog’a Publicaci—n Especial 10, p. 31-50

Green, G.N., and Selner, G.I., 1988, GSMARC--A program and procedure to convert GSMAP data bases into ARC/INFO coverages; GSDARC, a counterpart program for GSDRAW data bases and an ARC/INFO procedure to topologically structure resultant data: U.S. Geological Survey Open-File Report 88-430-A (16 p.) and B (a 5.25-inch diskette).

Marcano, Iris, Lugo, Elis, and Rivero, Nelson, 1991, Geolog’a y geomorfolog’a de la frontera con Colombia, entre la Piedra de Cocuy y Maroa, al suroeste del Territorio Federal Amazonas, Venezuela:  CVG-TECMIN Grupo Inventario internal report.

Mart’nez, Felix, 1991, Mapa geol—gico del area R’o Cunucunuma: Congreso Geol—gico de la Frontiera de Venezuela, San Cristobal, Venezuela, September 9-13, 1991.

McCandless, G.C., 1962, Reconnaissance geology of the northwest region of the State of Bol’var, Venezuela: Caribbean Journal of Science, v. 2, no. 4, p. 145-155.

Mendoza, Vicente, Moreno, L.A., Barrios, Fernando, Rivas, Duggar, Mart’nez, Jesśs, Lira, Pedro, Sardi, Gustavo, and Ghosh, S.K., 1977, Geolog’a de la parte norte del Territorio Federal Amazonas, Venezuela (informe en progreso): Congreso Geol—gico Venezolano, 5th, Caracas, 1977, Memoria, v.1, p. 363-404.

Mendoza-S., Vicente, 1977, Evoluci—n tect—nica del Escudo de Guayana, in Petzall, C., ed., Memoria Segundo [II] Congreso Latinoamericano de Geolog’a, Tomo III, Caracas, November 11-16, 1973: Venezuela, Direcci—n de Geolog’a, Boletin de Geolog’a,  Publicaci—n Especial 7, v. 3, p. 2237-2270.

Reid, A.R., and Bisque, R.E., 1975, Stratigraphy of the diamond-bearing Roraima Group, Estado Bol’var, Venezuela: Colorado School of Mines Quarterly Bulletin, v. 70, no. 1, p. 61-82.

Schruben, P.G., 1986, MRDS-REV, a mineral occurrence/deposit database for microcomputer: U.S. Geological Survey Open-File Report 86-34, 55 p.

Schruben, P.G., 1995, Geology of the Venezuelan Guayana Shield at 1:500,000 scale--A digital representation of maps published by the U.S. Geological Survey: U.S. Geological Survey Open-File Report 95-493, 11 p. and a web page.

Selner, G.I., and Taylor, R.B., 1987, GSDRAW and GSMAP version 4.0; prototype programs for the IBM PC and compatible microcomputers to assist compilation and publication of geologic maps and illustrations: U.S. Geological Survey Open-File Report 87-496-A (documentation, 90 p.), B (executable 5.25-inch diskette), C (source-code 5.25-inch diskette), and D (two executable utility program diskettes, each 5.25 inches).

Sidder, G.B., and Mendoza-S., Vicente, 1991, Geology of the Venezuelan Guayana Shield and its relation to the entire Guayana Shield: U.S. Geological Survey Open-File Report 91-141, 59 p., 2 plates.

Sidder, G.B., Garc’a G., AndrŽs, and Stoeser, J.W., eds., in press, Geology and mineral deposits of the Venezuelan Guayana Shield: U.S. Geological Survey Bulletin 2124.

Soares, M.A., 1985, Estudio petrogr‡fico de la estructura alcalina La Churuata, Territorio Federal Amazonas: Congreso Geol—gico Venezolano, 6th, Caracas, Memoria, v. 4, p. 2117-2158.

Stewart, J.H., 1994, Geologic map of part of the San Fernando de Apure 2ˇx3ˇ quadrangle, Venezuela: U.S. Geological Survey Miscellaneous field studies map MF-2247.

Stewart, J.H., Mart’nez, FŽlix, and Brooks, W.E., 1994, Geologic map of the Ciudad Piar and part of the Ciudad Bolivar 2ˇx3ˇ quadrangles, Bolivar State, Venezuela: U.S. Geological Survey Miscellaneous Field Studies Map MF-2246, scale 1:500,000.

Teggin, D.E., Mart’nez, M., and Palacios, G., 1985, Un estudio preliminar de las diabasas del Estado Bol’var, Venezuela, in Espejo C., An’bal, R’os-F., J.H., Pimentel de Bellizzia, Nelly, and Pardo, A.S., eds., Petrolog’a, geoqu’mica, y geocronolog’a,   VI Congreso Geol—gico Venezolano, Caracas, Memoria, v. 4, p. 2159-2206.

U.S. Geological Survey, 1986, Digital line graphs from 1:24,000-scale maps: U.S. Geological Survey US GeoData Data Users Guide 1, 109 p. 

U.S. Geological Survey, 1987, Digital line graphs from 1:2,000,000-scale maps: U.S. Geological Survey US GeoData Data Users Guide 3, 71 p.

U.S. Geological Survey, 1989, Digital line graphs from 1:100,000-scale maps: U.S. Geological Survey US GeoData Data Users Guide 2, 88 p.

U.S. Geological Survey and Corporaci—n Venezolana de Guayana, TŽcnica Minera, C.A., 1993, Geology and Mineral Resource Assessment of the Venezuelan Guayana Shield: U.S. Geological Survey, Bulletin 2062, 121 p. 8 plates.

Wentworth, C.M., and Fitzgibbon, T.T., 1991, Alacarte user manual, version 1.0: U.S. Geological Survey Open-File Report 91-587-C, 267 p.

Wynn, J.C., Olmore, S.D., Mendoza, Vicente, Mart’nez, Miguel, Rinc—n, HaydŽe, Garc’a, AndrŽs, Rivero, Nelson, Rend—n, InŽs, Marcano, Iris, Lugo, Elis, and Schruben, P.G., 1994, Geologic map of the Venezuela part of the Atabapo 2ˇx3ˇ quadrangle, Amazonas Federal Territory, Venezuela: U.S. Geological Survey Miscellaneous Field Studies Map MF-2240, scale 1:500,000.

Wynn, J.C., Olmore, S.D., Mendoza, Vicente, Garc’a, AndrŽs, Mart’nez, Miguel, and Schruben, P.G., 1994, Geologic map of the Venezuela part of the R’o Mavaca 2ˇx3ˇ quadrangle, Amazonas Federal Territory, Venezuela: U.S. Geological Survey Miscellaneous Field Studies Map MF-2241, scale 1:500,000.

Wynn, J.C., Olmore, S.D., Mendoza, Vicente, Garc’a, AndrŽs, Mart’nez, Miguel, Tovar, Frank, Rend—n, InŽs, Rinc—n, HaydŽe, Mart’nez, FŽlix, Lugo, Elis, and Schruben, P.G., 1994, Geologic map of the Venezuela part of the La Esmeralda 2ˇx3ˇ quadrangle, Amazonas Federal Territory, Venezuela: U.S. Geological Survey Miscellaneous Field Studies Map MF-2244, scale 1:500,000.

Wynn, J.C., Olmore, S.D., Mendoza, Vicente, Garc’a, AndrŽs, Rend—n, InŽs, Estanga, Yasmin, Rinc—n, HaydŽe, Mart’nez, FŽlix, Lugo, Elis, Rivero, Nelson, and Schruben, P.G., 1994, Geologic map of the Venezuela part of the Puerto Ayacucho 2ˇx3ˇ quadrangle, Amazonas Federal Territory, Venezuela: U.S. Geological Survey Miscellaneous Field Studies Map MF-2245, scale 1:500,000.

Wynn, J.C., Olmore, S.D., Mendoza, Vicente, Rinc—n, HaydŽe, Garc’a, AndrŽs, Rivero, Nelson, Rend—n, InŽs, Gray, Floyd, Marcano, Iris, Lugo, Elis, and Schruben, P.G., 1994, Geologic map of the Venezuela part of the Piedra de Cocuy 2ˇx3ˇ quadrangle, Amazonas Federal Territiory, Venezuela: U.S. Geological Survey Miscellaneous Field Studies Map MF-2243, scale 1:500,000.





DIGITAL PRODUCTION TECHNIQUES

	The linework for all the quadrangles was originally digitized by Jeff Wynn with GSMAP (Selner and Taylor, 1987), a USGS-authored map editing and publishing program.  Conversion from GSMAP to ARC/INFO was accomplished with GSMARC (Green and Selner, 1988).  The three northern quadrangles were later re-scanned on an Tektronix 4991 autovectorizing drum scanner by Paul Schruben from the geologists' revised drawings.  The arcs and polygons were tagged in ARC/INFO and the oriented point symbols such as bedding and joint symbols were created with Alacarte (Wentworth and Fitzgibbon, 1991).  




MAP PROJECTION

	The map projection is Equidistant Conic with the following parameters for all quadrangles:

   Sphere                               Clarke 1866 spheroid
   1st standard parallel                         9  0  0.000
   2nd standard parallel                         4  0  0.000
   central meridian                            -66  0  0.000
   latitude of projection's origin               0  0  0.000
   false easting (meters)                            0.00000
   false northing (meters)                           0.00000





CAUTIONS RELATING TO USE OF THE MAPS

	One of the advantages of digital maps is the ability to change the map scale.  However, the users of this disc should respect the intentions of the authors and recognize certain limitations of digital maps.  The Venezuelan MF series maps on this disc are intended to be used at a scale of 1:500,000; they are not intended to be used at a more detailed (larger) scale.  A Venezuela 2ˇx3ˇ degree quadrangle measures about 17 inches high by 26 inches wide at 1:500,000 scale.  
	The "quadrangle" maps in this publication cover somewhat more or less than 2ˇx3ˇ depending on the specific map.  For instance, the Guri map (Cox and others, 1993) contains all of the Guri quadrangle and the southern part of the Tucupita quadrangle.  The entire study area in the southeast part of Venezuela, known as the Venezuelan Guayana Shield, is about 36 inches tall at 1:1 million scale, which is the published scale for Bulletin 2062 (USGS and Corporaci—n Venezolana de Guayana, TŽcnica Minera, C.A., 1993).  
	Furthermore, the geologic map is primarily a bedrock map, which depicts geologic materials present beneath the soil or relatively thin mantles of surficial deposits, not necessarily the surficial materials themselves.  Indeed, the study area contains so much surficial cover and standing water that much of the mapping was accomplished with geophysical methods as opposed to directly examining rock outcrops. 





ONLINE FILES

	Some of the files on this CD will be available on the internet at the following internet address:

http://minerals.er.usgs.gov/vz/dds-46.html

	The page will also list any bugs and errors discovered in the CD-ROM after release.



GRAPHICS FORMATS AVAILABLE ON THE DISC

1) ARC/INFO Export

	These coverages are used for spatial analysis, derivative products, and to-scale plots on the Versatec electrostatic plotter.  Compatible with Environmental Systems Research Institute's ARC/INFO Version 6.1.2 or later.  The files are simple text and should be transmitted in ASCII mode except for the *.gra plot files, which are binary.  


2) ARC/INFO Graphics, Adobe Illustrator, Portable Document Format (PDF), and Postscript formats

The geologic map in ARC/INFO Graphics, Adobe Illustrator, PDF, and Postscript formats are located in directory "arcunix7/vz".  All are derived from the ARC/INFO ".gra" file using the POSTSCRIPT command.


3) ArcView format

	ArcView is an easy-to-use graphics display package by the authors of ARC/INFO.  This CD-ROM contains ArcView coverages for both UNIX and Microsoft Windows 3.x.  It also contains export files that can be copied to other ARC/INFO platforms and imported to ArcView.  ArcView 1 keys are in the "arcunix6" directory.  The ArcView 3 key for the "vz" directory is in the "arcunix7"directory.


4) U.S. Geological Survey Digital Line Graph (DLG) Optional format (U.S. Geological Survey, 1986, 1987, and 1989).

	The DLG Optional format is a U.S. Geological Survey standard for storing topologically structured files.  It results in a compact ASCII file that is compatible with a variety of graphics software.  Only the geology, faults, and correlation chart layers were converted to this format.  The polygons and arcs are tagged, but the text annotation is not present because the DLG conversion software does not support annotation.

5) Tagged image file format (TIFF)

	The geologic map and mineral deposit maps from Bulletin 2062 were scanned on a color scanner and saved as TIFF files.  The larger files are compressed under PKZIP.





ARCVIEW AND ARC/INFO FILES

	These files are compatible with ArcView 1 and ARC/INFO Version 6.1.2 or later.  The files are contained in 11 directories.  Ten of those directories contain coverages for the individual quadrangle publications.  The eleventh directory, "vz",  contains the same information but in the form of a combined map with all the quadrangles tiled together into a single coverage.  ArcView 1 keys are in the "arcunix6" directory.  The ArcView 3 key for the "vz" directory is in the "arcunix7"directory.  There are no ArcView 3 keys for the individual quadrangles.
	The coverages for the individual quadrangles have the same features as the combined coverage.  The only differences are in some of the file names.  For instance, the place names and city points in the individual quadrangles are stored in files called "*anno5.e00" as opposed to "places.e00" for the combined coverage.  
	The 11 directory structure is repeated in each of three formats:  export, raw UNIX, and PC ARCVIEW.


EXPORT FILES

	The export files are stored in the "export" directory.  The same export files are used for both ARCVIEW and ARC/INFO.  Each directory contains an IMPORT.AML program which imports all the coverages, lookup tables, etc.  The "vz" directory contains lookup tables and markersets necessary for plotting the individual quadrangles.  Before launching ARCVIEW, the "av.mrk" and "av.txt" files should be copied to the ARCVIEW home directory, usually the root or login directory.  
	The directories containing the export files on the CD are actually ARC/INFO workspaces for UNIX.  For other platforms it may be necessary to launch ARC/INFO, create each of the 11 workspaces and import  the coverages from those new workspaces.  For instance, for the "vz" directory:

arc
cw vz
q
cd vz
cp /pdd/dds46/export/vz/* .
arc
&r import

The directory structure on the CD is as follows:

export  main directory
   at    Atabapo
   ay    Puerto Ayacucho
   ca    R’o Caura
   es    La Esmeralda
   gu    Guri, Tucupita
   ma    R’o Mavaca
   pc    Piedra de Cocuy
   pi    Ciudad Piar, Ciudad Bolivar
   se    Santa Elena
   sf    San Fernando de Apure
   vz    combined coverages.  Also necessary to plot individual quads.


RAW UNIX COVERAGES:

	The raw coverages are in directory "arcunix6" and "arcunix7".  These can be copied to your UNIX machine with the following command:

cp -r /pdd/dds46/arcunix7



PC ARCVIEW COVERAGES:

	The PC ARCVIEW coverages are stored in directory "arcpc".  These files were converted directly from the UNIX version with the C program PCWKSP.


RUNNING THE PLOT PROGRAMS

	Each of the 11 directories contains a plot program for that area.  The plot programs rely on lookup tables in the "vz"  combined coverages directory.  So the "vz"  combined coverages directory should be copied or imported to hard disk before executing the plot program.  The resulting .gra file was converted to PostScript .eps with the ARC POSTSCRIPT command.  The polygon colors are for a Versatec plotter or display screen.





INSTALLING ARCVIEW 1

     This section contains instructions for installing and launching 
ArcView 1 for Windows and launching instructions for ArcView 1 for UNIX.  

Installation instructions for ArcView 1 for Microsoft Windows:

1) Please observe the following system requirements:

   80386 or better CPU
   Math coprocessor recommended
   Windows 3.0 or higher but not Windows 95
   4 Mb of RAM, 8 strongly recommended
   15 Mb of disk space
   Super VGA graphics system, 256 colors, 640x480 pixels minimum, 
      1024x768 pixels strongly recommended
   Microsoft compatible mouse
   Windows-supported printer

2) Decide where you are going to put ArcView 1 on your hard drive.  You must have 15 Mb of hard disk space.

3) Launch Windows.  Launch the File Manager.  Use the File Manager to find the CD-ROM drive and the \DDS46\ARCVIEW directory.  Double-click on 
ARCVIEW.EXE.  This starts the self-installing procedure.  At the licensing agreement document select the File menu, Exit.  ARCVIEW asks for a hard disk drive letter designation and a directory name to store the program.  The default is \ARCVIEW1.

4) When the install finishes, ArcView will tell you to examine SETUP.TXT and use it to modify AUTOEXEC.BAT and CONFIG.SYS.  Exit from Windows and use the following instructions modified from SETUP.TXT.  

Add the following environment variables to the C:\AUTOEXEC.BAT file:

    set AVHOME=c:\arcview1         (or wherever you decide to put it)
    set PATH=%PATH%;%AVHOME%\bin   (Add Arcview1's bin directory
                                   to the path )    
    set HOME=c:\arcview1           (or wherever you decide to put it)
    set TEMP=c:\temp               (Make sure the directory
                                   exists.  A RAM disk works the
                                   best, i.e, TEMP=d:\.  This
                                   variable should already be
                                   present if Windows has been 
                                   installed.)

Add the following line to the C:\CONFIG.SYS file:

    FILES=65

Rename the original lineset.  Copy the custom lineset from the DDS-46 CD- ROM.

    CD C:\ARCVIEW1\SYMBOLS
    REN AV.LIN AV_ORIG.LIN
    COPY D:\DDS46\DATAFILE\AVPCCOV\AV.LIN

5) Launch Windows.  Launch the File Manager again and copy the DDS46\ARCPC directory to your hard disk.  This step is optional but ArcView runs very slowly if the coverages are located on the CD-ROM.

Double-click on the ArcView icon.  Navigate the drive and directory menus to D:\DDS46\DATAFILE.  Double-click on the COSTA.AV view.  ArcView will ask to search for the GEOL coverage.  Select "Yes".  Navigate to the AVPCCOV folder and double-click on the GEOL file.  The ArcView Teacher will automatically find the full path to the rest of the coverages and launch the view.  Select the "File" menu, "Save As".  Save the view  so the next time you launch it, the path will be remembered.  






USING ARCVIEW 1

	The CD-ROM includes coverages that can be displayed with ArcView 1 (Environmental Systems Research Institute, Inc., 1992).  ArcView is an easy-to-use graphics display package by the authors of ARC/INFO.  ArcView displays the same coverages and images as ARC/INFO.  ArcView 1 is available  for UNIX Macintosh and Microsoft Windows 3.x computers.  This CD-ROM contains ArcView 1 for Windows 3.x programs but not ArcView for UNIX or Macintosh programs.  It does, however, contain coverages and views for both types of computers. 
	See "Installing ArcView 1" for instructions on installing and launching ArcView 1.  After ArcView is launched, the Table of Contents or map key appears on the left and the map on the right.  ArcView has a time-saving feature called interruptible re-draw.  This means that the tools, menu items and themes in the Table of Contents are selectable even while ArcView is re-drawing the map.  A mouse-click or mouse-drag will interrupt the drawing and take effect within a few seconds.  There is no need to wait for complicated maps to finish drawing if you already know what you want to do next.
	The initial width of the Table of Contents is too narrow to see all the text in the key.  The width can be increased by dragging on the edge of the table with the mouse.  Increasing the width of the Table of Contents causes it to overlap the map, but the map can be brought to the foreground by clicking on its title bar or edge.
	The individual layers (data themes) in the Table of Contents are turned on and off in the display by selecting the checkboxes along the left side of the map key.  Legends below individual themes can be turned on and off by dragging on the triangle on the right side of the key.  Colors of points, lines, and polygon fill can be changed by double-clicking a theme, selecting the legend checkbox in the Properties dialog, then double-clicking on the color.
	Zooming in and out are accomplished in many ways in ArcView.  One way is to select a theme or themes by single-clicking on the items in the Table of Contents so they appear slightly raised.  Single-click again to de-select them.  Choose just the items you want to zoom to, then select the "fit-selected-features-to-window" icon, which is the second icon from the left in the map window.  It looks like a down arrow over a stack of paper.  For instance, the "Venezuela national boundary" theme will give the widest view, "Index map" the next widest, "Geology, all quadrangles" the next widest, and individual quadrangles the smallest.  In each quadrangle, the Scale bar theme zooms out to see all the text and map.  This is the default selection as the CD is shipped.
	Another way to zoom in is with the "zoom-to-a-box" tool on the tool palette.  The tool palette can be brought to the foreground with the "Windows" menu, "Tools..." item.  Just select the dashed-line-box tool, which is the second from the bottom on the left, then drag in a diagonal movement across the area you wish to zoom to.
	If you view the "Rock unit names" theme, be sure to turn on the "Rock unit name leaders" as well.  Otherwise some unit names appear to float in the wrong unit.
	The order of layers in the Table of Contents is critical.  All layers are opaque, and the color-fill polygons obscure everything beneath them.  For this reason, color-fill themes are positioned lowest on the key and duplicated as non-filled versions higher up in the key.  For instance, "Geology polygons" is low in the Table of Contents because it obscures everything beneath it.  There is also a non-filled version called "Geology arcs" higher up in the key.  Should it be necessary to change the order of items in the Table of Contents, they can be dragged to a new position with the mouse.  For instance, "Index map, colored countries" is positioned fairly high in the key for a color-fill theme.  To draw geology outlines on top of it, just drag the index map theme to a position below the geology outlines theme.  
	To create hard copy of the ArcView 1 graphics screen, select the camera icon on the main display screen.  This creates an encapsulated PostScript (EPS) file of the display image, which can be printed with standard commercial graphics software.
	Use the "File" menu, "Open..." item to select other views:

Area                                                        file name
-------------------------------------------------------------------------
Venezuelan Guayana Shield, all quadrangles                    vz.av
Guri and southern part of the Tucupita 2ˇx3ˇ quadrangles      gu.av
Ciudad Piar and part of the Ciudad Bolivar 2ˇx3ˇ quadrangles  pi.av
San Fernando de Apure 2ˇx3ˇ quadrangle (Bolivar part)         sf.av
Santa Elena 2ˇx3ˇ quadrangle (Venezuela part)                 se.av
R’o Caura 2ˇ by 3ˇ quadrangle                                 ca.av
Puerto Ayacucho 2ˇx3ˇ quadrangle (Venezuela part)             ay.av
La Esmeralda 2ˇx3ˇ quadrangle (Venezuela part)                es.av
Atabapo 2ˇx3ˇ quadrangle (Venezuela part)                     at.av
R’o Mavaca 2ˇx3ˇ quadrangle (Venezuela part)                  ma.av
Piedra de Cocuy 2ˇx3ˇ quadrangle (Venezuela part)             pc.av





ARCVIEW 1 FILES

	The following table shows the ArcView 1 table of contents items and the source coverages:

ArcView views and themes                                file name
-------------------------------------------------------------------------

Venezuelan Guayana Shield, all quadrangles              vz.av

Venezuela national boundary                             vzctry
Venezuela province boundary                             vzprov
Scale bar annotation                                    scale
Scale bar                                               scale
Place names                                             places
Place points                                            places
Roads                                                   vzrd
Outer quad outline                                      vzout
Outer quad outline, lat/long numbers                    vzout
Latitude/longitude tics                                 vztc
Index map annotation                                    index
Index map lat/long grid only                            grid
Index map, colored countries, lat/long grid             index
Streams annotation                                      vzst
Streams                                                 vzst
Mineral deposits                                        deposit
Linear features annotation                              vzft
Linear features                                         vzft
A. Permissive domains annotation                        raanno
A. Permissive domains leaders                           raanno
A. Permissive domains for selected Fe, Au, Sn,          ra
     Cu deposits  
A. Permissive domains poly arcs only                    ra
B. Permissive domains structure annotation              rbstruct
B. Permissive domains structure lines                   rbstruct
B. Permissive domains annotation                        rbanno
B. Permissive domains leaders                           rbanno
B. Permissive domains for selected Pb-Zn, Ni-Cu,        rb
     diamond, kaolin deposits 
B. Permissive domains poly arcs only                    rb
Correlation of map units annotation                     vzcor
Correlation of map units polygons                       vzcor
Buried magnetic bodies                                  vzma
Rock unit labels                                        vzlab
Rock unit labels leaders                                vzlab
Geology arcs                                            vzge
Geology polygons                                        vzge


Guri and southern part of the Tucupita 2ˇx3ˇ            gu.av
   quadrangles

Index map, latitude/longitude tics                      vztc
Index map, annotation                                   index
Index map, lat/long grid only                           grid
Index map, colored countries, lat/long grid             index
Guri, quadrangle lat/long tics                          gutc
Guri, quadrangle lat/long numbers                       guout
Guri, quadrangle outline                                guout
Guri, place name annotation                             guanno5
Guri, city points                                       guanno5
Guri, roads                                             gurd
Guri, province boundary                                 gupl
Guri, streams annotation                                gust
Guri, streams                                           gust
Guri, linear feature annotation                         guft
Guri, linear features                                   guft
Guri, correlation of map units annotation               gucor
Guri, correlation of map units polygons                 gucor
Guri, map key annotation                                guleg
Guri, map key points                                    gulegpt
Guri, map key arcs                                      guleg
Guri, map key polygons                                  guleg
Guri, scale bar annotation                              guscale
Guri, scale bar                                         guscale
Guri, rock unit labels                                  gulab
Guri, rock unit labels leaders                          gulab
Guri, geology arcs                                      guge
Guri, geology polygons                                  guge


Ciudad Piar and part of the Ciudad Bolivar 2ˇx3ˇ        pi.av
   quadrangles

Index map, latitude/longitude tics                      vztc
Index map, annotation                                   index
Index map, lat/long grid only                           grid
Index map, colored countries, lat/long grid             index
Ciudad Piar, quadrangle lat/long tics                   pitc
Ciudad Piar, quadrangle lat/long numbers                piout
Ciudad Piar, quadrangle outline                         piout
Ciudad Piar, place name annotation                      pianno5
Ciudad Piar, city points                                pianno5
Ciudad Piar, roads                                      pird
Ciudad Piar, province boundary                          pipl
Ciudad Piar, streams annotation                         pist
Ciudad Piar, streams                                    pist
Ciudad Piar, linear feature annotation                  pift
Ciudad Piar, linear features                            pift
Ciudad Piar, structural trends from SLAR                pisr
Ciudad Piar, correlation of map units annotation        picor
Ciudad Piar, correlation of map units polygons          picor
Ciudad Piar, map key annotation                         pileg
Ciudad Piar, map key points                             pilegpt
Ciudad Piar, map key arcs                               pileg
Ciudad Piar, map key polygons                           pileg
Ciudad Piar, scale bar annotation                       piscale
Ciudad Piar, scale bar                                  piscale
Ciudad Piar, rock unit labels                           pilab
Ciudad Piar, rock unit labels leaders                   pilab
Ciudad Piar, kimberlite area annotation                 pima
Ciudad Piar, kimberlite area                            pima
Ciudad Piar, geology arcs                               pige
Ciudad Piar, geology polygons                           pige


San Fernando de Apure 2ˇx3ˇ quadrangle (Bolivar part)   sf.av

Index map, latitude/longitude tics                      vztc
Index map, annotation                                   index
Index map, lat/long grid only                           grid
Index map, colored countries, lat/long grid             index
San Fernando, quadrangle lat/long tics                  sftc
San Fernando, quadrangle lat/long numbers               sfout
San Fernando, quadrangle outline                        sfout
San Fernando, place name annotation                     sfanno5
San Fernando, city points                               sfanno5
San Fernando, province boundary                         sfpl
San Fernando, streams annotation                        sfst
San Fernando, streams                                   sfst
San Fernando, linear features                           sfft
San Fernando, correlation of map units annotation       sfcor
San Fernando, correlation of map units polygons         sfcor
San Fernando, map key annotation                        sfleg
San Fernando, map key points                            sflegpt
San Fernando, map key arcs                              sfleg
San Fernando, map key polygons                          sfleg
San Fernando, scale bar annotation                      sfscale
San Fernando, scale bar                                 sfscale
San Fernando, rock unit labels                          sflab
San Fernando, rock unit label leaders                   sflab
San Fernando, geology arcs                              sfge
San Fernando, geology polygons                          sfge


Santa Elena 2ˇx3ˇ quadrangle (Venezuela part)           se.av

Index map, latitude/longitude tics                      vztc
Index map, annotation                                   index
Index map, lat/long grid only                           grid
Index map, colored countries, lat/long grid             index
Santa Elena, quadrangle lat/long tics                   setc
Santa Elena, quadrangle lat/long numbers                seout
Santa Elena, quadrangle outline                         seout
Santa Elena, place name annotation                      seanno5
Santa Elena, city points                                seanno5
Santa Elena, roads                                      serd
Santa Elena, province boundary                          sepl
Santa Elena, stream annotation                          sest
Santa Elena, streams                                    sest
Santa Elena, linear feature annotation                  seft
Santa Elena, linear features                            seft
Santa Elena, correlation of map units annotation        secor
Santa Elena, correlation of map units polygons          secor
Santa Elena, map key annotation                         seleg
Santa Elena, map key points                             selegpt
Santa Elena, map key arcs                               seleg
Santa Elena, map key polygons                           seleg
Santa Elena, scale bar annotation                       sescale
Santa Elena, scale bar                                  sescale
Santa Elena, rock unit labels                           selab
Santa Elena, rock unit labels leaders                   selab
Santa Elena, geology arcs                               sege
Santa Elena, geology polygons                           sege


R’o Caura 2ˇ by 3ˇ quadrangle                           ca.av

Index map, latitude/longitude tics                      vztc
Index map, annotation                                   index
Index map, lat/long grid only                           grid
Index map, colored countries, lat/long grid             index
R’o Caura, quadrangle lat/long tics                     catc
R’o Caura, quadrangle lat/long numbers                  caout
R’o Caura, quadrangle outline                           caout
R’o Caura, place name annotation                        caanno5
R’o Caura, city points                                  caanno5
R’o Caura, province boundary                            capl
R’o Caura, stream annotation                            cast
R’o Caura, streams                                      cast
R’o Caura, linear features annotation                   caft
R’o Caura, linear features                              caft
R’o Caura, correlation of map units annotation          cacor
R’o Caura, correlation of map units polygons            cacor
R’o Caura, map key annotation                           caleg
R’o Caura, map key points                               calegpt
R’o Caura, map key arcs                                 caleg
R’o Caura, map key magnetics                            caleg
R’o Caura, map key polygons                             caleg
R’o Caura, scale bar annotation                         cascale
R’o Caura, scale bar                                    cascale
R’o Caura, rock unit labels                             calab
R’o Caura, rock unit labels leaders                     calab
R’o Caura, buried magnetic bodies                       cama
R’o Caura, geology arcs                                 cage
R’o Caura, geology polygons                             cage


Puerto Ayacucho 2ˇx3ˇ quadrangle (Venezuela part)       ay.av

Index map, latitude/longitude tics                      vztc
Index map, annotation                                   index
Index map, lat/long grid only                           grid
Index map, colored countries, lat/long grid             index
Puerto Ayacucho, quadrangle lat/long tics               aytc
Puerto Ayacucho, quadrangle lat/long numbers            ayout
Puerto Ayacucho, quadrangle outline                     ayout
Puerto Ayacucho, place name annotation                  ayanno5
Puerto Ayacucho, city points                            ayanno5
Puerto Ayacucho, roads                                  ayrd
Puerto Ayacucho, province boundary                      aypl
Puerto Ayacucho, streams annotation                     ayst
Puerto Ayacucho, streams                                ayst
Puerto Ayacucho, linear features                        ayft
Puerto Ayacucho, correlation of map units annotation    aycor
Puerto Ayacucho, correlation of map units polygons      aycor
Puerto Ayacucho, map key annotation                     ayleg
Puerto Ayacucho, map key points                         aylegpt
Puerto Ayacucho, map key arcs                           ayleg
Puerto Ayacucho, map key magnetics                      ayleg
Puerto Ayacucho, map key polygons                       ayleg
Puerto Ayacucho, scale bar annotation                   ayscale
Puerto Ayacucho, scale bar                              ayscale
Puerto Ayacucho, rock unit labels                       aylab
Puerto Ayacucho, rock unit labels leaders               aylab
Puerto Ayacucho, section line annotation                aylabcr
Puerto Ayacucho, section line on map                    aylabcr
Puerto Ayacucho, section annotation                     aycrm
Puerto Ayacucho, section leaders                        aycrm
Puerto Ayacucho, section geology arcs                   aycrm
Puerto Ayacucho, section geology polygons               aycrm
Puerto Ayacucho, buried mag annotation                  aymalab
Puerto Ayacucho, buried mag leaders                     aymalab
Puerto Ayacucho, buried magnetic bodies                 ayma
Puerto Ayacucho, geology arcs                           ayge
Puerto Ayacucho, geology polygons                       ayge


La Esmeralda 2ˇx3ˇ quadrangle (Venezuela part)          es.av

Index map, latitude/longitude tics                      vztc
Index map, annotation                                   index
Index map, lat/long grid only                           grid
Index map, colored countries, lat/long grid             index
La Esmeralda, quadrangle lat/long numbers               esout
La Esmeralda, quadrangle outline                        esout
La Esmeralda, place name annotation                     esanno5
La Esmeralda, city points                               esanno5
La Esmeralda, province boundary                         espl
La Esmeralda, streams annotation                        esst
La Esmeralda, streams                                   esst
La Esmeralda, linear features                           esft
La Esmeralda, structural trends from SLAR               essr
La Esmeralda, correlation of map units annotation       escor
La Esmeralda, correlation of map units polygons         escor
La Esmeralda, map key annotation                        esleg
La Esmeralda, map key points                            eslegpt
La Esmeralda, map key arcs                              esleg
La Esmeralda, map key polygons                          esleg
La Esmeralda, rock unit labels                          eslab
La Esmeralda, rock unit labels leaders                  eslab
La Esmeralda, buried magnetic bodies                    esma
La Esmeralda, geology arcs                              esge
La Esmeralda, geology polygons                          esge


Atabapo 2ˇx3ˇ quadrangle (Venezuela part)               at.av

Index map, latitude/longitude tics                      vztc
Index map, annotation                                   index
Index map, lat/long grid only                           grid
Index map, colored countries, lat/long grid             index
Atabapo, quadrangle lat/long numbers                    atout
Atabapo, quadrangle outline                             atout
Atabapo, place name annotation                          atanno5
Atabapo, swamp symbols                                  atanno5
Atabapo, province boundary                              atpl
Atabapo, streams annotation                             atst
Atabapo, streams                                        atst
Atabapo, linear features                                atft
Atabapo, correlation of map units annotation            atcor
Atabapo, correlation of map units polygons              atcor
Atabapo, map key annotation                             atleg
Atabapo, map key arcs                                   atleg
Atabapo, map key magnetics                              atleg
Atabapo, map key polygons                               atleg
Atabapo, scale bar annotation                           atscale
Atabapo, scale bar                                      atscale
Atabapo, rock unit labels                               atlab
Atabapo, rock unit labels leaders                       atlab
Atabapo, buried magnetic bodies                         atma
Atabapo, geology arcs                                   atge
Atabapo, geology polygons                               atge


R’o Mavaca 2ˇx3ˇ quadrangle (Venezuela part)            ma.av

Index map, latitude/longitude tics                      vztc
Index map, annotation                                   index
Index map, lat/long grid only                           grid
Index map, colored countries, lat/long grid             index
R’o Mavaca, quadrangle lat/long numbers                 maout
R’o Mavaca, quadrangle outline                          maout
R’o Mavaca, place name annotation                       maanno5
R’o Mavaca, city points                                 maanno5
R’o Mavaca, streams annotation                          mast
R’o Mavaca, streams                                     mast
R’o Mavaca, linear features                             maft
R’o Mavaca, correlation of map units annotation         macor
R’o Mavaca, correlation of map units polygons           macor
R’o Mavaca, map key annotation                          maleg
R’o Mavaca, map key arcs                                maleg
R’o Mavaca, map key magnetics                           maleg
R’o Mavaca, map key polygons                            maleg
R’o Mavaca, scale bar annotation                        mascale
R’o Mavaca, scale bar                                   mascale
R’o Mavaca, rock unit labels                            malab
R’o Mavaca, rock unit labels leaders                    malab
R’o Mavaca, geology arcs                                mage
R’o Mavaca, buried magnetic bodies                      mama
R’o Mavaca, geology polygons                            mage


Piedra de Cocuy 2ˇx3ˇ quadrangle (Venezuela part)       pc.av

Index map, latitude/longitude tics                      vztc
Index map, annotation                                   index
Index map, lat/long grid only                           grid
Index map, colored countries, lat/long grid             index
Piedra de Cocuy, quadrangle lat/long numbers            pcout
Piedra de Cocuy, quadrangle outline                     pcout
Piedra de Cocuy, place name annotation                  pcanno5
Piedra de Cocuy, city points                            pcanno5
Piedra de Cocuy, province boundary                      pcpl
Piedra de Cocuy, streams annotation                     pcst
Piedra de Cocuy, streams                                pcst
Piedra de Cocuy, linear features                        pcft
Piedra de Cocuy, structural trends from SLAR            pcsr
Piedra de Cocuy, correlation of map units annotation    pccor
Piedra de Cocuy, correlation of map units polygons      pccor
Piedra de Cocuy, map key annotation                     pcleg
Piedra de Cocuy, map key points                         pclegpt
Piedra de Cocuy, map key arcs                           pcleg
Piedra de Cocuy, map key magnetics                      pcleg
Piedra de Cocuy, map key polygons                       pcleg
Piedra de Cocuy, scale bar annotation                   pcscale
Piedra de Cocuy, scale bar                              pcscale
Piedra de Cocuy, rock unit labels                       pclab
Piedra de Cocuy, rock unit labels leaders               pclab
Piedra de Cocuy, geology arcs                           pcge
Piedra de Cocuy, buried magnetic bodies                 pcma
Piedra de Cocuy, geology polygons                       pcge



ARCVIEW 3 FILES

	The ArcView 1 view for the enitre study area, "vz.av", has been converted to ArcView 3 format, "vz.apr".  It is in "arcunix7/vz" directory.  The coverages are in ARC/INFO 7 format so are useable on Mac, PC and UNIX platforms.





COVERAGE DATA DEFINITION

GEOLOGY POLYGON ATTRIBUTES:

The ARC/INFO VZGE.PAT file consists of:

COLUMN   ITEM NAME        WIDTH OUTPUT  TYPE INDEXED?
    1  AREA                   4    12     F  
    5  PERIMETER              4    12     F  
    9  VZGE#                  4     5     B  
   13  VZGE-ID                4     5     B  
   17  FMATN                  6     6     C  upper-case rock-unit code
   23  PTYPEI                 3     3     C  for sorting units into groups
   26  LC                     6     6     C  mixed-case rock-unit code 
   32  DESC                  60    60     C  
   92  PTYPES                69    69     C  


	PTYPEI is a two-digit integer that is used to sort the units into groups of related rocks.  The third character in PTYPEI is a space for appearance in the legend.  PTYPES is composed of PTYPEI, PTYPE, and DESC.  It also can be used to sort correctly by unit group.  All the short rock descriptions are in the INFO file DESC in alphabetical order (abbreviations: Fm, Formation; gr, grained; Gp Group; E, Early; Prot, Proterozoic; rx, rocks; Plio, Pliocene; qtz, quartz; Sg, Supergroup; congl, conglomerate; qtzite, quartzite; Mid, Middle; terr, terrane; seds, sedimentary rocks; metaseds, metasedimentary rocks):

LC    DESC
blank Unmapped area                                              
d     Diabase - mafic dikes undivided (Mesozoic to M Proterozoic)
dioritFenitized diorite & tonalite at Cerro Impacto              
ic    Carbonatite(?) intrusion of Cerro Impacto                  
Qal   Alluvial deposits of sand, gravel, and silt (Quaternary)   
QTm   Mesa Fm. siltstone and sandy siltstone (Pleistocene & Plio)
water                                                            
Xa    Amphibolite schist containing andesine (E Prot)            
XAgr  Granitic rx of Imataca Complex (E Prot and/or Archean)     
XAi   Imataca Complex orthogneiss and paragneiss (Archean)       
XAm   Migmatite & gneiss of Imataca Complex (E Prot or Archean)  
Xbc   Basement complex granite to granodiorite gneiss (E Prot)   
Xcb   Caballape Fm felsic metatuff and phyllite (E Prot)         
Xcc   Cicapra Fm (Carichapo Gp) mafic to intermed metatuff E Prot
Xce   El Callao Fm (Carichapo Gp) greenstone, greenschist (E Prot
Xcg   Granitic rocks of Cuchivero Group (Early Proterozoic)      
Xco   Cinaruco Fm qtzite, sericitic qtzite, schist (E Prot)      
Xcv   Caicara Fm (Cuchivero Gp) rhyodacitic-rhyolitic tuff E Prot
Xf1   Felsic metatuff and flows (Early Proterozoic)              
Xf2   Felsic metatuff and flows, eugeosynclinal terrane (E Prot) 
Xg    Calc-alkaline granite & other silicic plutonic rx (E Prot) 
Xg1   Metagabbro (greenstone belts) (Early Proterozoic)          
Xg2   Metagabbro (eugeosynclinal terrane) (Early Proterozoic)    
Xgr   Granitic rocks, mostly quartz monzonite (Early Proterozoic)
Xgu   Granitic silicic to intermediate intrusive rocks (E Prot)  
Xlc   Los Caribes Fm arkose, polymict congl, phyllite (E Prot)   
Xm1   Meta-mafic to intermediate flow and pyroclastic rx (E Prot)
Xm2   Mafic to intermediate metalava and metatuff (E Proterozoic 
Xma   Maracapra Fm red beds, felsic volcanics (E Proterozoic)    
Xmo   Moriche Fm metasedimentary conglomerates (E Prot)          
Xmp   Intrusive rx of San Carlos metamorphic-plut terrane (E Prot
Xmu   Greenstone belt rocks, undivided (Early Proterozoic)       
Xpr   Pre-Roraima Gp sedimentary rx clay-rich sandstone (E Prot) 
Xs1   Schist, phyllite, metatuffs, and metavolcanic rx (E Prot)  
Xs2   Muscovite schist and phyllite, eugeosynclinal terr (E Prot)
Xsm   Seds and metaseds of uncertain affinity qtz arenite (E Prot
Xsp   Supamo Complex sodic granitic rx, paragneiss, etc. (E Prot)
Xu1   Metaperidotite, metapyroxenite, serp & talc schist (E Prot)
Xu2   Ultramafic rx metaperidotite, metapyroxenite, etc. (E Prot)
Xui   Ultramafic intrusive rx in La Flor-Carapo area (E Prot)    
Xyf   Yuruari Fm (Pastora Sg) felsic metatuff (E Prot)           
Xys   Yuruari Fm Pastora Sg qtz muscovite schist, phyllite E Prot
Ylg   Late granite intrusive in, and doming Roraima seds (M Prot)
Yp    Parguaza granite, massive, porphryitic & biotite (M Prot)  
YXac  Alkaline intrusive complexes (Middle to Early Proterozoic) 
YXr   Roraima Group (undivided) qtz arenite, arkose M &/or E Prot
YXra  Auyantepuy Fm (Roraima Gp) quartz arenite, arkose M, E Prot
YXrc  Canaima Fm (Roraima Gp) qtz arenite, arkose, etc. M, E Prot
YXrg  Guaiquinima Fm (Roraima Gp) qtz arenite, arkose M, E Prot  


GEOLOGY ARC TYPES:

	The VZGE.AAT items are:

COLUMN   ITEM NAME        WIDTH OUTPUT  TYPE 
    1  FNODE#                 4     5     B  
    5  TNODE#                 4     5     B  
    9  LPOLY#                 4     5     B  
   13  RPOLY#                 4     5     B  
   17  LENGTH                 4    12     F  
   21  VZGE#                  4     5     B  
   25  VZGE-ID                4     5     B  
   29  CODE                   3     3     I  
   32  P1                     3     3     I  
   35  P2                     3     3     I  

CODE   DESC
   1   international boundary
   2   surface water body
  30   geological contact
  32   geological contact hidden


FAULT ARCS:

	The VZFT.AAT attribute table contains:

COLUMN   ITEM NAME        WIDTH OUTPUT  TYPE INDEXED?
    1  FNODE#                 4     5     B  
    5  TNODE#                 4     5     B  
    9  LPOLY#                 4     5     B  
   13  RPOLY#                 4     5     B  
   17  LENGTH                 4    12     F  
   21  VZFT#                  4     5     B  
   25  VZFT-ID                4     5     B  
   29  CODE                   3     3     I  
   32  FTYPEI                 3     3     C  
   35  DESC                  60    60     C  
   95  FTYPES                63    63     C  


CODES AND DESCRIPTIONS FOR FAULTS AND OTHER COVERAGES:

	The INFO file FTYPE contains:

CODE  FTYPEI  DESC
  20       1  fault
   6       2  fault - inferred (dashed)
   7       3  fault - implied (dotted)
  79       4  thrust fault
 127       5  sag fault
  17       6  fold axis
  21       7  graben
  26       8  graben - hidden
  25       9  shear zone
  72      10  U or Th anomaly
  81      11  structural trend
  70      12  ring structure
 103      13  iron formations
  18      14  major magnetic gradient
  16      15  fault movement and fold arrows
   1      16  international boundary
   4      17  province boundary
   2      18  surface water body
   3      18  tributary
   5      19  main road
  42      20  secondary road
  30      21  geological contact
  32      22  geological contact hidden


PERMISSIVE TRACT POLYGONS:

	The RA.PAT and RB.PAT polygon attribute files contain:

 COL  ITEM NAME         WDTH OPUT TYP 
    1  AREA                4   12  F  
    5  PERIMETER           4   12  F  
    9  RA#                 4    5  B  
   13  RA-ID               4    5  B  
   17  FMATN               6    6  C  
   23  TRACT               5    5  C  
   28  DESC               64   64  C  
   92  KEY                69   69  C  


TRACT MAP A

KEY
IIa  Low-sulfide gold-quartz vein deposits, permissive
IIb  Low-sulfide gold-quartz vein deposits, low probability
Ia   Algoma iron and sedimentary manganese deposits, permissive
Ib   Algoma iron and sedimentary manganese deposits, low probability
VI   Tin greisen deposits
VIII Porphyry copper and volcanic-hosted magnetite deposits


TRACT MAP B

KEY
III  Kuroko-type massive sulfide deposits
IV   Synorogenic-synvolcanic Ni-Cu & related platinum deposits
V    Carbonatite deposits and diamond-bearing kimberlite pipes
VII  Sedimentary kaolin deposits


MINERAL DEPOSIT POINTS:

	The original list of mineral deposits in Bulletin 2062 (USGS and Corporaci—n Venezolana de Guayana, TŽcnica Minera, C.A., 1993) was not available in digital form at the time of publication of this CD-ROM.  Consequently, a new retrieval was made from the USGS Mineral Resources Data System (Schruben, 1986).  This also takes advantage of any updates that may have taken place in the data base.  The retrieval netted 2353 deposits in Venezuela, Guayana, Surinam, French Guinea, and Brazil, of which 459 deposits fell in the study area.  The following fields are present in the DEPOSIT.PAT file:

COLUMN   ITEM NAME        WIDTH OUTPUT  TYPE N.DEC  ALTERNATE NAME
    1  AREA                   4    12     F      3                
    5  PERIMETER              4    12     F      3                
    9  DEPOSIT#               4     5     B      -                
   13  DEPOSIT-ID             4     5     B      -                
   17  RECNO                  7     7     C      -                
   24  SITE                  40    40     C      -                
   64  CTRY.CODE              2     2     C      -                
   66  STATE                 13    13     C      -                
   79  LATITUDE               9     9     C      -                
   88  LONGITUDE             10    10     C      -                
   98  COMMOD_GP             11    11     C      -                
  109  COMMOD                34    34     C      -                
  143  COMMOD1                4     4     C      -                
  147  ORE.MAT               60    60     C      -                
  207  DEP.TYPE              40    40     C      -                
  247  DEP.COMMENTS          80    80     C      -                
  327  MODEL                 40    40     C      -                
  367  HOST.RK.NAME          60    60     C      -                
  427  HOST.RK.TYPE          60    60     C      -                
  487  HOST.ROCK.AGE         10    10     C      -                
  497  ASOC.RK.NAME          60    60     C      -                
  557  ASOC.RK.TYPE          60    60     C      -                
  617  ASSOC.ROCK.AGE        10    10     C      -                
  627  ALTERATION            80    80     C      -                
  707  GEOL.COMMENTS         80    80     C      -                
  787  GEN.COMMENTS          80    80     C      -                
  867  REFERENCE             80    80     C      -                
 
COMMOD1 is used to assign symbols to the sites for plotting.  Please note that some fields are truncated from the original MRDS information, particularly the REFERENCE field.





DLG OPTIONAL FORMAT

	The DLG format is a U.S. Geological Survey standard for storing topologically structured files.  It results in a compact ASCII file that is compatible with a variety of graphics software.  
	The Venezuelan Guayana Shield geology, faults, and correlation chart have been converted to Digital Line Graph (DLG) Optional format files.  The DLG files contain tagged polygons and arcs.  Annotation text is not supported in the DLG conversion software and is not present in the DLG files.  The DLG file directory follows:

    cor.dlg      correlation of map units in Equidistant Conic projection
    cordd.dlg    correlation of map units in decimal degrees
    ft.dlg       faults in Equidistant Conic projection
    ftdd.dlg     faults in decimal degrees
    ge.dlg       geology in Equidistant Conic projection
    gedd.dlg     geology in decimal degrees
    ptype.unl    rock unit names, descriptions, colors for Versatec plotter
    scale.dlg    scale bar in Equidistant Conic projection
    scaledd.dlg  scale bar in decimal degrees
    vzline.unl   fault and contact line types

	Although the conversion to ARC/INFO is more easily accomplished with ARC/EXPORT files, which are included elsewhere on this disc, the following instructions for converting DLG files to ARC/INFO may be illustrative for converting DLG files to non-ARC/INFO platforms.
	These methods for converting DLG files to ARC/INFO coverages have been adapted from ARC/INFO manuals (Environmental Systems Research Institute, 1990):

1) Copy the .dlg and .unl files from the CD-ROM.  For instance, from a UNIX prompt, type:

arc
cw vz                             create arc/info workspace
q
cd vz
cdrom in
cp /pdd/cdrom/datafiles/dlg/*.unl .
cdrom out

2) Launch ARC/INFO and create a lookup table for the rock unit codes:

arc
tables
define ptype.lut
Enter Command: define ptype.lut
      1
Item Name: major1
Item Width: 6
Item Output Width: 6
Item Type: i
      7
Item Name: fmatn
Item Width: 6
Item Output Width: 6
Item Type: c
     13
Item Name: ptypei
Item Width: 3
Item Output Width: 3
Item Type: c
     16
Item Name: lc
Item Width: 6
Item Output Width: 6
Item Type: c
     22
Item Name: color
Item Width: 3
Item Output Width: 3
Item Type: i
     25
Item Name: desc
Item Width: 60
Item Output Width: 60
Item Type: c
     85
Item Name:
Enter Command: alter fmatn
COLUMN   ITEM NAME        WIDTH OUTPUT  TYPE N.DEC  ALTERNATE NAME
    7  FMATN                  6     6     C      -
Item name:
Item output width:
Item type:
Alternate item name: cross
COLUMN   ITEM NAME        WIDTH OUTPUT  TYPE N.DEC  ALTERNATE NAME
    7  FMATN                  6     6     C      -    CROSS

Enter Command: alter color
COLUMN   ITEM NAME        WIDTH OUTPUT  TYPE N.DEC  ALTERNATE NAME
   22  COLOR                  3     3     I      -
Item name:
Item output width:
Item type:
Alternate item name: symbol
COLUMN   ITEM NAME        WIDTH OUTPUT  TYPE N.DEC  ALTERNATE NAME
   22  COLOR                  3     3     I      -    SYMBOL
Enter Command: get ptype.unl

The geology polygon lookup table should look as follows:

COLUMN   ITEM NAME  WIDTH OUTPUT  TYPE N.DEC  ALTERNATE NAME     INDEXED?
    1  MAJOR1           6     6     I      -                        -
    7  FMATN            6     6     C      -    CROSS               -
   13  PTYPEI           3     3     C      -                        -
   16  LC               6     6     C      -                        -
   22  COLOR            3     3     I      -    SYMBOL              -
   25  DESC            60    60     C      -                        -

Enter Command: list major1 fmatn ptypei lc color
Record  major1 fmatn  ptypei lc     color
     1       1 DEEP          deep     0
     2       2 BLACK         black    1
     3       3 POS           pos      0
     4       4 NEG           neg      0
     5       5 KIMB          Kimb     0
     6       6 H2O     1     water   61
     7       7 QAL     2     Qal    129
     8       8 QTM     3     QTm      4
     9       9 YXAC    5     YXac   213
    10      10 YLG     6     Ylg    106
    11      11 IC      7     ic      72
    12      12 YXR     8     YXr    123
    13      13 YXRA    9     YXra   123
    14      14 YXRG   10     YXrg   123
    15      15 YXRC   11     YXrc   123
    16      16 XPR    12     Xpr    123
    17      17 AC     13     ac     213
    18      18 XGU    14     Xgu    188
    19      19 XG     15     Xg     247
    20      20 XCG    16     Xcg    187
    21      21 DIORIT 17     diorit 187
Continue? n

Enter Command: list desc
Record  desc
     1
     2
     3
     4
     5
     6
     7  Alluvial deposits of sand, gravel, and silt (Quaternary)
     8  Mesa Fm. siltstone and sandy siltstone (Pleistocene & Plio)
     9  Mesa Fm. siltstone and sandy siltstone (Pleistocene & Plio)
    10  Alkaline intrusive complexes (Middle to Early Proterozoic)
    11  Intrusive rocks in and doming Roraima seds (Mid Prot)
    12  Carbonatite intrusion of Cerro Impacto
    13  Roraima Group (undivided) qtz arenite, arkose M &/or E Prot
    14  Auyantepui Fm (Roraima Gp) quartz arenite, arkose M, E Prot
    15  Canaima Fm (Roraima Gp) qtz arenite, arkose, etc. M, E Prot
    16  Guaiquinima Fm (Roraima Gp) qtz arenite, arkose M, E Prot  
    17  Pre-Roraima Gp sedimentary rx clay-rich sandstone (E Prot)
    18  Granitic silicic to intermediate intrusive rocks (E Prot)
    19  Calc-alkaline granite & other silicic plutonic rx (E Prot)
    20  Grantitc rocks of Cuchivero Group (Early Proterozoic)
    21  fenitized diorite & tonalite at Cerro Impacto
Continue? n


3) Create a lookup table for the faults and contacts.

tables
Enter Command: define vzline.lut
      1
Item Name: major1
Item Width: 6
Item Output Width: 6
Item Type: i
      7
Item Name: code
Item Width: 3
Item Output Width: 3
Item Type: i
     10
Item Name: line
Item Width:
Integer value expected.
Item Width: 3
Item Output Width: 3
Item Type: i
     13
Item Name: expl
Item Width: 45
Item Output Width: 45
Item Type: c
     58
Item Name:

Enter Command: alter line
COLUMN   ITEM NAME        WIDTH OUTPUT  TYPE N.DEC  ALTERNATE NAME
   10  LINE                   3     3     I      -
Item name:
Item output width:
Item type:
Alternate item name: symbol
COLUMN   ITEM NAME        WIDTH OUTPUT  TYPE N.DEC  ALTERNATE NAME
   10  LINE                   3     3     I      -    SYMBOL

Enter Command: it

COLUMN   ITEM NAME        WIDTH OUTPUT  TYPE N.DEC  ALTERNATE NAME     INDEXED?
    1  MAJOR1                 6     6     I      -                        -
    7  CODE                   3     3     I      -                        -
   10  LINE                   3     3     I      -    SYMBOL              -
   13  EXPL                  45    45     C      -                        -


Enter Command: get vzline.unl
43 Records Selected.

Enter Command: list
Record  MAJOR1 CODE LINE EXPL
     1       1   0    9  MAP BORDER NEAT LINE
     2       2   1  109  INTL BORDER LONG & SHORT DASH
     3       3   2    4  SURFACE WATER BODIES
     4       4   3  111  NAMED TRIBUTARIES - BLUE
     5       5   4  120  PROVINCES (STATE BOUNDARIES) WAS 118
     6       6   5   41  MAIN ROADS SOLID/OPEN
     7       7   6  106  FAULT - DASHED INFERRED UNDER RX
     8       8   7  117  FAULT - DOTTED IMPLIED UNDER H20-Q
     9       9   8  112  THRUST TEETH ON LEFT
    10      10   9    1  SECTION LINE
    11      11  10    1  BOXES; SCALE
    12      12  11   33  DIRT ROAD
    13      13  15    5  MAG DERIVED FAULT
    14      14  16    1  LEADERS ARROWS
    15      15  17    1  FOLD AXIS
    16      16  18  101  MAJOR MAG GRADIENT - DOT
    17      17  19  106  FAULT - HIDDEN. WAS GSMAP 32
    18      18  20    5  LINEAMENT; FAULT
    19      19  21   85  GRABEN HATCH ON RIGHT SIDE OF LINE
    20      20  23   86  GRABEN HATCH ON LEFT SIDE OF LINE
    21      21  25    5  SHEAR ZONE
    22      22  26   87  GRABEN HIDDEN HATCH ON RIGHT
Continue? n
Enter Command: q stop


4) The dlgarc command creates .pcode and .acode INFO files which are used to link the .lut tables to the coverage.  Some of this linking may be automatic in non-ARC/INFO conversions.  If not, the technique is to use the common -id field to join the .acode and .pcode files to the coverage, then use major1 as the common field to link ptype.lut and vzline.lut to the coverage.

Choose a dlg file to convert - Equidistant Conic (ge.dlg) or Decimal Degrees (gedd.dlg).  The following example is for the Equidistant Conic coverages:


kill ge all
dlgarc optional ../dlg/ge.dlg ge
build ge
build ge line

/*   join the major1 item from ge.pcode using the -id as key
joinitem ge.pat ge.pcode ge.pat ge-id ge-id

/*   join the unit names, colors and description from ptype.lut using major1
joinitem ge.pat ptype.lut ge.pat major1 major1

/*   join major1 which contains the line type from ge.acode
joinitem ge.aat ge.acode ge.aat ge-id ge-id

/*   join major1 which contains the contact line type from ge.acode
joinitem ge.aat vzline.lut ge.aat major1 major1 

kill ft all
dlgarc optional ../dlg/ft.dlg ft
build ft line

/*   join the major1 item from ft.acode using the -id as key
joinitem ft.aat ft.acode ft.aat ft-id ft-id

/*   join major1 which contains the fault line type from ft.acode
joinitem ft.aat vzline.lut ft.aat major1 major1 

kill cor all
dlgarc optional ../dlg/cor.dlg cor
build cor
build cor line

/*   join the major1 item from cor.pcode using the -id as key
joinitem cor.pat cor.pcode cor.pat cor-id cor-id

/*   join the unit names, colors and description from ptype.lut using major1
joinitem cor.pat ptype.lut cor.pat major1 major1

/*   join major1 which contains the line type from cor.acode
joinitem cor.aat cor.acode cor.aat cor-id cor-id

/*   join major1 which contains the contact line type from cor.acode
joinitem cor.aat vzline.lut cor.aat major1 major1 

kill scale all
dlgarc optional ../dlg/scale.dlg scale
build scale line

/*   join the major1 item from scale.acode using the -id as key
joinitem scale.aat scale.acode scale.aat scale-id scale-id

/*   join major1 which contains the fault line type from scale.acode
joinitem scale.aat vzline.lut scale.aat major1 major1 




DESCRIPTION OF MAP UNITS

SEDIMENTARY ROCKS

Qal - Alluvial deposits (Quaternary)--Sand, gravel, and silt

QTm - Mesa Formation (Pleistocene and Pliocene)--Siltstone and sandy 
   siltstone, generally reddish; massive to laminated. Unconsolidated 
   gravel and sand in upper part.  Called Tm on some earlier maps

YXr - Roraima Group (Middle and (or) Early Proterozoic), undivided-
   Compilation of regional ages indicates an age of 1,900-1,500 Ma (Sidder 
   and Mendoza-S., 1991)
   YXra - Auyantepuy Formation--Mainly quartz arenite and minor arkose; 
          forms steep cliffs and flat-topped mesas. Thickness 300-700 m. 
          Equivalent to Matau’ Formation of Reid and Bisque (1975)
   YXrg - Guaiquinima Formation--Fine-grained quartz arenite and arkose that 
          are cross stratified; red, green, and greenish-gray jasper 
          composed of devitrified and silicified ash and small crystals of 
          quartz and feldspar.  Weathers to form flat or gently sloping 
          topography. Upper part is mostly covered with debris from 
          overlying Auyantepuy Formation. Several hundreds of meters thick. 
          Equivalent to all but the lowermost part of the UaimapuŽ 
          Formation of Reid and Bisque (1975)
   YXrc - Canaima Formation--Quartz arenite, arkose, conglomeratic arenite, 
          conglomerate, siltstone, and shale.  Abundant crossbeds in 
          arenite and arkose units.  Weathers to form cliffs on resistant 
          arenite, arkose, and conglomerate units and slopes on relatively 
          nonresistant siltstone, shale, and silty arenite units.  About 
          1,000-2,000 m thick.  Equivalent to UairŽn and Kukuen‡n 
          Formations and lowermost part of UaimapuŽ Formation of Reid and 
          Bisque (1975)

Xpr - Pre-Roraima Group sedimentary rocks (Early Proterozoic)--Fine-grained 
   to very fine grained, clay-rich sandstone, locally containing granule-
   size quartz grains.  Interbedded with red shale and sandy shale 
   (Brice–o, 1982)

Xco - Cinaruco Formation (Early Proterozoic)--Quartzite and sericitic 
   quartzite and minor amounts of sericite-quartz schist and phyllite, 
   ferruginous quartzite, and one or more intra-formational quartzite 
   conglomerates (McCandless, 1962)

Xlc - Los Caribes Formation (Early Proterozoic)--Weakly metamorphosed 
   sequence of reddish arkose, polymict conglomerate, and finely laminated 
   phyllite with minor felsic tuff

Xma - Maracapra Formation (Early Proterozoic)--Weakly metamorphosed red 
   beds and felsic volcanic rocks


EUGEOSYNCLINAL TERRANE

Xm2 - Mafic to intermediate metalava and metatuff (Early Proterozoic)--
   Chlorite+epidote±actinolite schist and semischist, and greenstone, 
   commonly with relict pyroxene phenocrysts.  Relict textures suggest that
   protoliths were amygdaloidal flows and lithic- and crystal-rich tuffs

Xf2 - Felsic metatuff and flows (Early Proterozoic)--Quartz+muscovite±
   chloritoid semischist with relict phenocrysts of partially resorbed 
   quartz and broken plagioclase replaced by albite.  Groundmass mainly 
   devitrified glass.  Traces of relict lapilli locally abundant

Xs2 - Muscovite schist and phyllite (Early Proterozoic)--Quartz+muscovite±
   chlorite±chloritoid±ankerite schist and phyllite, and subordinate 
   quartzite or metachert derived from sedimentary and felsic volcanic 
   rocks.  Ankeritic rocks weather to ferruginous schist and phyllite


MAFIC AND ULTRAMAFIC ROCKS OF
THE EUGEOSYNCLINAL TERRANE

Xg2 - Metagabbro (Early Proterozoic)

Xu2 - Ultramafic rocks (Early Proterozoic)--Mainly metaperidotite and 
   metapyroxenite, serpentinite, and talc schist.  Cumulus texture locally 
   preserved


VOLCANIC ROCKS

Xcv - Caicara Formation of the Cuchivero Group (Early Proterozoic)--
   Unmetamorphosed ash-flow tuffs and rhyolitic to dacitic flows and 
   breccias.  A U-Pb age of 1,980 Ma was obtained from ash-flow tuff near 
   Icabarś (Brooks and others, in press).  Called Xc on some maps


INTRUSIVE ROCKS

d - Diabase (Mesozoic to Early Proterozoic)--Dark-gray to greenish-gray, 
   fine- to coarse-grained diabase of tholeiitic composition.  Forms dikes 
   and sills.  K-Ar ages of diabase in region are 210-200 Ma and 1,700-
   1,600± 0.8 Ma (Teggin and others, 1985; Sidder and Mendoza, 1991). 
   In cases where locations were determined from side looking airborne radar 
   (SLAR) interpretation or from aeromagnetic data, the map symbol is 
   crosshatched

Yp - Parguaza Granite (Middle Proterozoic)--Massive, coarsely crystalline, 
   porphyritic granite and biotite granite commonly with rapakivi texture  
   These rocks have been dated about 1,545 Ma, (zircon age; 1,531±39Ma 
   (Rb/Sr age) Gaudette and others, 1978). The Parguaza Granite is 
   reported by Mendoza and others (1977) and Ghosh (1985) to be 
   unconformably overlain by the Roraima Group, although isotopic dates on 
   the Parguaza Granite (about 1,545 Ma) are within the possible age span 
   of the Roraima Group (1,900 to 1,545 Ma)(Ghosh, 1985; Sidder and 
   Mendoza-S., 1991). These age relations can be explained if the Roraima 
   Group varies significantly in age within the Guayana Shield; that is, 
   the Roraima Group may be relatively young (<1,545 Ma) where it 
   reportedly (Mendoza and others, 1977; Ghosh, 1985) rests on the Parguaza 
   Granite but may be older than this in the eastern parts of the Guayana 
   Shield

Ylg - Late granite typically penetrating through and doming Roraima Group
   sediment (Middle Proterozoic)--In Ca–o Yagua (lat 3ˇ25' N., long 65ˇ40' 
   W.), one body was mapped as coarsely equigranular granodiorite with 
   pronounced rapakivi texture.  In the southern part of the R’o Negro (lat 
   1ˇ10' N., long 66ˇ50' W.), a similar body named the Piedra de Cocuy was 
   described as a granodiorite with 20 percent biotite, 30 percent quartz, 
   40 percent feldspar, and 10 percent hornblende (Marcano and others, 
   written communication, 1991). These rocks are characterized by small, 
   subrounded, and generally strong magnetic anomalies and are commonly 
   visible in SLAR imagery

ic - Carbonatite intrusion of Cerro Impacto (Mesozoic to Early 
   Proterozoic)--Inferred primarily from geochemistry of the laterite (which 
   is enriched in Ta, Nb, Th, Ba, and rare earth elements (REE)) and barite 
   outcrops and from geophysical interpretation that indicates a magnetite-
   rich core.  Carbonatite underlies a north-trending ridge that has a thick 
   lateritic cover in a depression composed of fenitized granodiorite and 
   tonalite.  Age may be as young as 80 Ma (Mendoza and others, 1977) or as 
   old as 1,800 Ma as inferred from intrusive relationship with the granitic 
   rocks of the Cuchivero Group (1,900-1,800 Ma; Sidder and Mendoza-S., 
   1991)

YXac - Alkaline complexes (Middle and Early Proterozoic). Generally 
   small and rounded to subrounded.  The structure 2.5 km in diameter at 
   La Churuata (3o20'N, 65o25'W) intruded the base of the eastern flank 
   of Cerro Duida, southeast of Cerro Marahuaca, and has a Rb/Sr date of 
   1,300 Ma (Soares, 1985).  Its composition has been described as a 
   combination of "saturated syenites, quartz-syenites, nepheline 
   syenites, and granites", the latter apparently deriving from 
   assimilation of the sandstones from the surrounding Roraima 
   Formation.  Aegirine, riebeckite, biotite, zircon, monazite, and 
   bastnaesite have been identified.  This structure has associated U, 
   Th, REE, Zr, and Sn geochemical anomalies.  Another example in the 
   northeastern corner of La Esmeralda quadrangle (3o50'N, 63o10'W), is 
   coarsely crystalline, (phenocrysts from 1 to 2.5 cm), alkalic, with 
   apparent flow-banding of the feldspar crystals (Jeff Wynn, U.S. 
   Geological Survey, written communication, 1991). These rocks are 
   generally only very weakly magnetic, yet are often visible in the 
   SLAR imagery..  The examples in Caura quadrangle are inferred to be 
   similar based on interpretation of aeromagnetic data.  Called ac on some 
   maps

Xg - Calc-alkaline granite and other silicic plutonic rocks (Early 
   Proterozoic)--Mart’nez (1991) described these rocks as massive, coarse-
   grained, gray, equigranular biotite granites with rapakivi texture 
   similar to the Parguaza batholith.  These granites are seen west and 
   north of Cerro Duida (lat 4ˇ00' N., long 65ˇ30' W.) in the Amazonas 
   Federal Territory. These rocks are weakly to moderately magnetic, 
   commmonly with east-west to west-northwest trends in the magnetic 
   anomalies. Pronounced west-northwest-striking lineaments in the SLAR 
   imagery are characteristic, especially in the Atabapo quadrangle. 

XAgr - Granitic rocks intruding the Imataca Complex (Early Proterozoic and 
   (or) Archean)--Mostly quartz monzonite.  Age uncertain; may include 
   granitoids as old as Late Archean as well as granitoids of Early 
   Proterozoic age equivalent to the Supamo or Cuchivero Groups

XAm - Migmatite and gneiss associated with the Imataca Complex (Early 
   Proterozoic and (or) Archean)--Quartz monzonite, migmatite, and lineated 
   gneiss

Xcg - Granitic rocks of the Cuchivero Group (Early Proterozoic)--Includes 
   granites of Guaniamito, San Pedro, and Santa Rosal’a intruded into 
   volcanic rocks of the Caicara Formation.  Commonly equigranular to 
   porphyritic, medium to coarse grained, and locally foliated. 
   Phenocrysts include orthoclase, microcline, plagioclase, quartz, 
   biotite, muscovite, and accessory sphene, apatite, zircon, and 
   hornblende.  Rb-Sr isotopic age range of 1,900 to 1,800 Ma (Sidder and 
   Mendoza-S., 1991)

diorit - Fenitized zone in Xcg at Cerro Impacto--Caused by the underlying 
   carbonatite. Indicated by smooth depression on SLAR imagery

Xgu - Intrusive rocks, undivided (Early Proterozoic)--Underlying water-
   inundated plains and jungle in the southeastern Amazonas Federal 
   Territory. Where seen south and east of San Fernando de Atabapo (lat 
   3ˇ45' N., long 67ˇ40' W.), they are described as biotite hornblende 
   granites and granite gneisses (Marcano and others, 1991).  These rocks 
   are weakly magnetic and have no apparent trend

Xgr - Granitic rocks (Early Proterozoic)--Mostly quartz monzonite. 
   Porphyritic, medium to coarse grained, some inclusions of granodiorite. 
   May include potassic granitoids as old as the Supamo Complex and (or) 
   granitoids as young as or younger than the Cuchivero Group

Xsp - Supamo Complex (Early Proterozoic)--Sodic granitic rocks, paragneiss, 
   migmatite, granodiorite, and sparse pegmatite. About 2,230 to 2,050 Ma 
   (Sidder and Mendoza-S., 1991)



GREENSTONE BELT ROCKS OF THE
GUASIPATI-EL CALLAO AREAS

Xcb - Caballape Formation (Early Proterozoic)--Mainly felsic metatuff and 
   phyllite derived from laminated volcaniclastic siltstone and graywacke. 
   Metatuff contains plagioclase phenocrysts, resorbed phenocrysts of 
   quartz, wisps of pumice, and minor lithic clasts

Pastora Supergroup (Early Proterozoic)--Divided into:

   Yuruari Formation

Xyf - Felsic metatuff--Quartz±muscovite±calcite semischist. Contains relict 
   quartz and feldspar phenocrysts and traces of lapilli and breccia 
   clasts.  Minor greenstone

Xys - Muscovite schist and phyllite--Finely laminated quartz+muscovite±
   chloritoid±biotite±andalusite±sillimanite schist.  Locally contains 
   volcaniclastic metasandstone and felsic metatuff and breccia

   Carichapo Group

Xcc - Cicapra Formation--Mafic to intermediate metatuff.  Mainly albite+
   epidote±biotite amphibolite. Relict textures suggest interlayering of 
   tuff and volcaniclastic sandstone

Xce - El Callao Formation--Greenstone, greenschist and minor talc schist 
   and amphibolite. Relict pillow structure is common. Flows are commonly 
   intercalated with flow breccias. Fine-grained quartz-hematite rocks in 
   uppermost part.  Minor chert


GREENSTONE BELT ROCKS ELSEWHERE IN THE GUAYANA SHIELD

Xsm - Sedimentary and metasedimentary rocks (Early Proterozoic)--Rocks of 
   uncertain affinity along or near R’o Oris in southeastern Ciudad Piar 
   quadrangle.  Corresponds in part to La Quina Formation of Bellizzia-G. 
   and others (1976).  Hematitic quartz arenite; reddish phyllitic 
   siltstone; feldspathic arenite; conglomeratic arenite; quartz-sericite 
   phyllite; red, laminated, fine-grained meta-arenite with graded bedding 
   and erosional channels

Xma - Maracapra Formation of Bellizzia-G. and others (1976) (Early 
   Proterozoic)--Weakly metamorphosed red beds and felsic volcanic rocks

Xmu - Greenstone belt rocks, undivided (Early Proterozoic)--Gold-bearing, 
   greenstone belt rocks are reported in the upper R’o Orinoco headwaters, 
   La Esmeralda quadrangle.  The tremendous magnetic gradients in this area 
   tend to be sinuous and linear.  They resemble gradients of the greenstone 
   belt rocks in eastern Bol’var State. This terrane is distinguished by low 
   to moderate relief in the SLAR imagery

Xa - Amphibolite schist (Early Proterozoic)--Includes local coarse-grained 
   metagabbro

Xf1 - Felsic metatuff and flows (Early Proterozoic)--
   Quartz+muscovite±chlorite semischist with relict phenocrysts of 
   partially resorbed quartz and broken feldspar

Xm1 - Mafic to intermediate metalava and metatuff (Early Proterozoic)-- 
   Chlorite+albite+epidote±actinolite schist, semischist, and greenstone, 
   locally amygdaloidal.  Subordinate hornblende hornfels, albite-epidote 
   amphibolite and minor amphibolite.  Minor chert

Xs1 - Schist, phyllite, metatuff, and metavolcanic rocks (Early 
   Proterozoic)--Quartz-mica schist; quartz-sericite-chlorite schist; 
   sericitic meta-arenite; sericitic-chloritic phyllite; rhyolitic, 
   dacitic, andesitic, and basaltic metatuffs; minor metabasalt and meta-
   andesite

Xg1 - Metagabbro (Early Proterozoic)--Saussuritized and, locally, 
   amphibolitized metagabbro. Cumulus texture locally preserved

Xu1 - Ultramafic rocks (Early Proterozoic)--Mainly metaperidotite and 
   metapyroxenite, serpentinite, and talc schist

Xui - Ultramafic intrusive rocks in La Flor-Carapo area (Early 
   Proterozoic)--Medium- to coarse-grained pyroxenite sills; ophitic or 
   subophitic to cumulate textures; saussuritized plagioclase, 
   clinopyroxene altered to green hornblende, and sparse olivine



ROCKS OF THE IMATACA PROVINCE

XAi - Imataca Complex (Early Proterozoic and (or) Archean)--Amphibolite- to 
   granulite-facies quartzofeldspathic orthogneiss and paragneiss, commonly 
   garnet-bearing, and felsic granulite. Minor amounts of intermediate to 
   mafic orthogneiss, granulite, and charnockite. Metamorphosed iron 
   formations and ferruginous quartzite are shown by dotted lines on map.  
   Older than 2,800 Ma, the protolith is probably as old as 3,400 to 3,700 
   Ma (Sidder and Mendoza-S., 1991)


METAMORPHIC ROCKS

Xmo - Moriche Formation (Early Proterozoic)--Characterized at its type 
   locality (Cerro Moriche on the middle R’o Ventuari, lat 4ˇ40' N., long 
   66ˇ25' W.) as metasedimentary conglomerates, possible remnants of an 
   ancestral greenstone belt terrane eroded from the protolith (Ghosh, 
   1985). These rocks are highly magnetic and commonly follow major 
   structural lows along the middle and upper R’o Orinoco and R’o Mavaca. 
   They generally form long, linear bodies, some of which are folded by 
   regional metamorphic events, and are usually visible in the SLAR imagery

Xmp - Intrusive rocks of the San Carlos metamorphic-plutonic terrane (Early 
   Proterozoic)--Covering large parts of the southern Amazonas Federal 
   Territory.  These rocks are named for the type locality at San Carlos de 
   R’o Negro (lat 1ˇ50' N., long 67ˇ05'W.) and crop out along most of the 
   R’o Guain’a and R’o Negro.  They are described as granite, granite-
   porphyry, granite-gneiss, and augen-gneiss with relatively abundant 
   pegmatites (Marcano and others, 1991).  This terrane is characterized by 
   strong, sinuous, east-west- to N. 70ˇ W.-trending, elongate magnetic 
   anomalies stacked together

Xbc - Basement complex (Early Proterozoic)-Foliated granite to granodiorite 
   gneiss


Linear features:

Contact, dashed where inferred primarily from magnetic data
Fault, dashed where inferred, dotted where implied.  Includes lineaments recognized on SLAR
Fault, transverse, arrows show relative movement where known
Fault, thrust, sawteeth on upper plate
Fault--Bar and ball on downthrown side; dashed where inferred
Fold axis, anticline, overturned anticline, syncline
Graben bounding fault, tics on downthrown side, dashed where inferred
Major deep penetrating shear zone inferred from geologic mapping and radar imagery
U or Th anomaly
Linear, curvalinear, to circular structural features recognized on SLAR
Ring structure of unknown origin visible in SLAR--In some cases may represent a volcanic caldera
Banded iron formation and quartzite of the Imataca complex
Axis of strong pervasive magnetic gradient--May represent major hidden fault or suture; U, upthrown side; D, downthrown side
Water contact
Single line tributary
International boundary
Province boundary
Paved road


Point features:

Outcrop
Unimproved airstrip
Settlement
Bedding
Foliation
Joint, vertical joint
Inclined cleavage
Sinkhole