By
Ray E. Wells, Parke D. Snavely, Jr., Norman S. Macleod, Michael M. Kelly, Michael J. Parker, Johanna S. Fenton, and Tracey J. Felger
Open - File Report 95-670
This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards or with the North American Stratigraphic Code. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
This database, identified as "Geologic map of the Tillamook Highlands, Northwest Oregon Coast Range: A digital database," has been approved for release and publication by the Director of the USGS. Although this database has been subjected to rigorous review and is substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review. Furthermore, it is released on condition that neither the USGS nor the United States Government may be held liable for any damages resulting from its authorized or unauthorized use.
1995
This digital geologic map database represents the distribution and character of Cenozoic geologic strata in six 15' quadrangles covering most of the Tillamook Highlands in the northwest Oregon Coast Range. The geologic map was published as Open-File Report 94-21, the Geologic Map of the Tillamook Highlands, Northwest Oregon Coast Range, by Wells and others. The map was produced as an encapsulated Postscript file and is available from Open File Services or as an encapsulated Postscript file on the World Wide Web at https://pubs.usgs.gov/of/1994/of94-21/ . The database is largely compiled from new mapping at 1:48,000 and 1:24,000 scales by the authors, in combination with published and unpublished previous work. The geology is the work of the first five authors; the digital compilation of the database and production of this report is the work of the last two authors. Together with the accompanying text file (tilgeo.ps or tilgeo.txt), it provides the most recent synthesis of the stratigraphy and structural geology of the northern Coast Range uplift. Bedrock map units are identified by age and lithology following informal stratigraphic nomenclature of the U.S. Geological Survey. Quaternary units are divided into beach and dune deposits, fluvial deposits and terraces, and landslides. The scale of the source maps generally limits spatial resolution (scale) of the database to 1:48,000 or smaller. The content and character of the database files are described herein, along with three methods of obtaining the database.
DATABASE CONTENTS
The digital database consists of the geologic map database itself and the supporting data including base maps, annotation layers, specialized symbol sets, and text files. This database is divided into 6 sets of data based on 15' quadrangle boundaries which can be taken individually or as a complete data set. If the user has not chosen to acquire the entire data set, not all of the files listed below will be present. Data sets are listed by 15' quadrangle. The data is available in ARC/INFO export format.
ARC/INFO export files: NEHALEM 15' quadrangle, compressed tar file name: nehexp.tar.Z 3.9 MB compressed download file, 21.5 MB uncompressed data file neh_geo.e00 Faults, depositional contacts, and geologic unit identities neh_str.e00 Fold axes, oriented symbols (strike and dip information) neh_topo.e00 Base map neh_ann.e00 Labels for geologic units and faults ENRIGHT 15' quadrangle, compressed tar file name: enrexp.tar.Z 6.7 MB compressed download file, 36.6 MB uncompressed data file enr_geo.e00 Faults, depositional contacts, and geologic unit identities enr_alt.e00 Alteration zones enr_str.e00 Oriented symbols (strike and dip information) enr_topo.e00 Base map enr_ann.e00 Labels for geologic units and faults TIMBER 15' quadrangle, compressed tar file name: timexp.tar.Z 4.5 MB compressed download file, 25.2 MB uncompressed data file tim_geo.e00 Faults, depositional contacts, and geologic unit identities tim_str.e00 Fold axes, oriented symbols (strike and dip information) tim_topo.e00 Base map tim_ann.e00 Labels for geologic units and faults TILLAMOOK 15' quadrangle, compressed tar file name: tilexp.tar.Z 3.5 MB compressed download file, 19.1 MB uncompressed data file til_geo.e00 Faults, depositional contacts, and geologic unit identities til_str.e00 Oriented symbols (strike and dip information) til_topo.e00 Base map til_ann.e00 Labels for geologic units and faults til_wel.e00 Well locations BLAINE 15' quadrangle, compressed tar file name: blaexp.tar.Z 5.0 MB compressed download file, 27.1 MB uncompressed data file bla_geo.e00 Faults, depositional contacts, and geologic unit identities bla_str.e00 Fold axes, oriented symbols (strike and dip information) bla_topo.e00 Base map bla_ann.e00 Labels for geologic units and faults FAIRDALE 15' quadrangle, compressed tar file name: faiexp.tar.Z 3.5 MB compressed download file, 19.3 MB uncompressed data file fai_geo.e00 Faults, depositional contacts, and geologic unit identities fai_str.e00 Fold axes, oriented symbols (strike and dip information) fai_topo.e00 Base map fai_ann.e00 Labels for geologic units and faults Complete Data Set, compressed tar file name: all6exp.tar.Z 27.1 MB compressed download file, 148.9 MB uncompressed data file all6exp Includes all of the data listed above Accessory Data, compressed tar file name: symbolexp.tar.Z 0.05 MB compressed download file, 0.3 MB uncompressed data file symbolexp A directory containing custom symbolsets and fonts (not included with the ARC/INFO package), and an INFO directory with look-up tables used to match symbols, colors, etc. to the existing Open File Report 94-21 of the Tillamook map. The of95-670 Open File directory also includes the following files: tilgeo.ps Postscript version of the text file containing detailed unit descriptions and geological information which accompanied Open File Report 94-21. NOTE: This text file was written to accompany the entire data set (6 15' quadrangles). All geologic units or features referenced in this text may not appear on a single 15' quadrangle. tilgeo.txt ASCII version of tilgeo.ps (Open File Report 94-21 with no figures). tildb.ps Postscript version of this report. tildb.txt ASCII text file of this report without figures.ORGANIZATION OF THE DATA RELEASE
The database was compiled in ARC/INFO, a commercial Geographic Information System (Environmental Systems Research Institute, Redlands, California), and is available in uncompressed ARC export format (ARC/INFO version 6.1.1) in a compressed UNIX tar (tape archive) file. Tar and uncompress utilities are therefore required to extract the database from the tar file. Export files (.e00 extension) can be imported into ARC/INFO coverage format or can be read by some other Geographic Information Systems (such as MapInfo via ArcLink). The digital compilation was done using version 6.1.1 of ARC/INFO with version 2.0 of the menu interface ALACARTE (Fitzgibbon and Wentworth, 1991, Fitzgibbon, 1991, Wentworth and Fitzgibbon, 1991).
OBTAINING THE DIGITAL DATA
The digital data can be obtained in two ways: a. on the World Wide Web b. by requesting a DVDb. World Wide Web (WWW) site: On the U.S. Geological Survey Publications Server, go to https://pubs.usgs.gov.of/1995/of95-670 to get to the web page for these data. Once you have downloaded the data, follow the instructions for "Extracting the Database from the Tar file" below
c. Request a DVD from:
Tillamook Digital Database
c/o BWRG Data Coordinator
U.S. Geological Survey Do not omit any part of this address
345 Middlefield Road, M/S 975
Menlo Park, CA 94025
The compressed tar file will be sent on a DVD
Extracting the Database from the Tar file:
If you obtained the database on DVD:
put the DVD in your DVD drive
cd [local_directory] -go to a directory to receive the tar file
tar xvfb /dev/rstn -/dev/rstn is the tape device with n an integer
this puts the tar file in local_directory
uncompress [file].tar.Z -makes an uncompressed tar file [file].tar
cd local_directory2 -go to the directory that will hold the data
[file] (if different from local_directory)
tar xvfb {path to tar
file}/[file].tar -extract the [file] workspace from the tar file.
This process will create a directory for each quad in your local directory.
Import AMLs are included with the export format data. To convert the export files
into ARC coverage format, run the import AML scripts included in each directory:
arc: &run imp.amlDIGITAL COMPILATION
The geologic map information from twenty four 1:24,000 scale field maps was reduced and compiled at 1:48,000 scale on six stable originals created from the 7.5' bases. The geology was digitized from the six 1:48,000 map sheets, each of which represent a quadrangle (Tillamook, Nehalem, Enright, Timber, Fairdale, and Blaine) in the discontinued 15' map series. The author manuscripts (ink on mylar) were scanned using a Tektronix 4991 monochrome scanner with a resolution of 304.8 dots per inch. The scanned images were vectorized and transformed from scanner coordinates to projection coordinates using digital tics at quadrangle corners. The scanned lines were edited interactively using ALACARTE, unit boundaries were tagged as a contact or fault as appropriate, and scanning artifacts visible at 1:24,000 were removed.
Base Maps
Base Map layers were prepared from scale-stable printing negatives at 1:48,000 scale, of the U.S. Geological Survey Tillamook (1955 edition), Nehalem (1955 edition), Enright (1955 edition), Timber (1955 edition), Fairdale (1955 edition), and Blaine (1955 edition) 15' topographic maps. This old base was used because there were no funds for digitizing the 24 7.5' bases and because a base derived from 7.5' quadrangles was unsuitable for plotting images of the entire map area. Scanned and vectorized images were transformed from scanner coordinates to projection coordinates using digital tics at map corners. Scanning artifacts are common in the base map coverages, and they were not removed. The base is intended for reference only; no information other than location is attached to the lines.
Landslides
Although this database emphasizes bedrock relationships, a number of landslides are delineated. It is not, however, a complete inventory of landslides in the map area, nor does it distinguish between active and inactive slides.
Spatial Resolution
Uses of this digital geologic map should not violate the spatial resolution of the data. Although the digital form of the data removes the constraint imposed by the scale of a paper map, the detail and accuracy inherent in map scale are also present in the digital data. The fact that this database was compiled from 7.5' maps at a scale of 1:48,000 means that higher resolution information is generally not present in the dataset, although it may be useful locally at 1:24,000 in areas of closely spaced field observations. Plotting at scales larger than 1:48,000 generally will not yield greater real detail, although it may reveal fine-scale irregularities below the intended resolution of the database. Similarly, where this database is used in combination with other data of higher resolution, the resolution of the combined output will be limited by the lower resolution of these data. Note that although the base map layers also have a resolution of 1:48,000, discrepancies between geologic contacts and topography may occur. The base map layers are provided for reference only.
DATABASE SPECIFICS
The map databases consist of ARC coverages and supporting INFO files, which are stored in a UTM (Universal Transverse Mercator) projection (Table 1). Digital tics define a 15 minute grid of latitude and longitude with the tics corresponding to quadrangle corners.
Table 1 - ARC/INFO Map Projection Specifications PROJECTION UTM -Universal Transverse Mercator UNITS METERS -on the ground ZONE 10 -UTM zone PARAMETERS ENDThe content of the geologic database can be described in terms of the lines (arcs), areas (polygons) and the point locations (points) that compose the map. Descriptions of the database fields use the terms explained in Table 2.
Table 2 - Field Definition Terms ITEM NAME name of the database field (item) WIDTH maximum number of digits or characters stored OUTPUT output width TYPE B-binary integer, F-binary floating point number, I-ASCII integer, C-ASCII character string N. DEC. number of decimal places maintained for floating point numbersEach 15' quadrangle data set will include at least four ARC/INFO coverages: a geology layer (xxx_geo), a structure layer (xxx_str), an annotation layer (xxx_ann), and a base layer (xxx_topo), where xxx is the three-letter quadrangle name abbreviation. Some quadrangles may have additional layer types including alteration zones (xxx_alt) or well locations (xxx_wel).
Geology layers (xxx_geo) -
Geology layers contain lines and areas.
Lines -
The lines (arcs) are recorded as strings of vectors and are described in the
arc attribute table (Table 3). They define the boundaries of the map units
(contacts), faults, dikes, boundaries of open bodies of water, and the map
boundaries (fold axes are recorded on structure layers). These distinctions,
including the geologic identities of the unit boundaries, are recorded in the
LTYPE field according to the line types listed in Table 4. All line types listed
may not appear on any one 15' quadrangle.
Table 3 - Content of the Arc Attribute Tables of geology and structure layers ITEM NAME WIDTH OUTPUT TYPE N. DEC FNODE# 4 5 B starting node of arc (from node) TNODE# 4 5 B ending node of arc (to node) LPOLY# 4 5 B polygon to the left of the arc RPOLY# 4 5 B polygon to the right of the arc LENGTH 4 12 F 3 length of arc in meters [coverage]# 4 5 B unique internal control number [coverage]-ID 4 5 B unique identification number LTYPE 35 35 C line typeTable 4 - Line Types Recorded in the LTYPE Field of geology layers
contact, approx. located contact, certain contact, concealed contact, concealed, queried contact, inferred, queried dike, Tib dike, Tis fault, approx. located fault, certain fault, inferred, queried fault, concealed fault, concealed, queried thrust fault, approx. located thrust fault, certain thrust fault, concealed thrust fault, inferred, queried_ water boundary, certain map boundary, certain scratch boundaryThe geologic line types are ALACARTE line types that correlate with the geologic line symbols in the ALACARTE line set GEOL61.LIN according to the ALACARTE lines lookup table GEOL61.LUT. The LTYPE, "thrust fault, inferred, queried_" is equivalent to "thrust fault, inferred, queried" and is used to display question mark symbols according to fault orientation. The scratch boundary is used to close off areas with unknown areal extent for display purposes.
Areas -
Geologic map units (polygons) are described in the polygon attribute table
(Table 5) The identities of the map units are recorded in the PTYPE field by map
label (Table 6). All units listed may not appear on any one 15' quadrangle. Map
units are described more fully in the accompanying text file (tilgeo.ps or
tilgeo.txt).
Table 5 - Content of the Polygon Attribute Tables of geology layers
ITEM NAME WIDTH OUTPUT TYPE N. DEC AREA 4 12 F 3 area of polygon in square meters PERIMETER 4 12 F 3 length of perimeter in meters [coverage]# 4 5 B unique internal control number [coverage]-ID 4 5 B unique identification number PTYPE 35 35 C unit labelTable 6 - Map Units Recorded in the PTYPE Field of geology layers (See tilgeo.ps or tilgeo.txt for descriptions of units)
QTg Qb Qf Qls Qls? Qt Qtb Taa Tac Tacs Tal Tals Tam Tan Tba Tba? Tbc Tbcm Tbl Tbpl Tbpu Tbr Tbr? Tbru Tbs Tbs? Tbsu Tbu Tc Tc? Tchb Tcm Teib Tet Tgr Thbr Thpb Thpb? Ths Tiab Tib Tid Tidb Tidb? Tifs Tifs? Tigr Tk Tms Tmst Tn Tpb Tpb? Tpg Trsk Trsk? Tsb Tsbr Tsbr? Tsf Tsg Tspb Tts Twfs Ty Ty? Tybs Tyt Tyt? water
Structure layers (xxx_str) -
Structure layers contain points and annotation, and may contain lines if fold axes
are represented.
Points -
Points are described in the point attribute table (Table 7) Point types are
recorded in the PTTYPE field according to the point types listed in Table 8.
Points in the structure layer represent attitude measurements. Planar attitudes
record strike in the STRIKE field and dip in the DIP field. Linear attitudes
record bearing in the STRIKE field and plunge in the DIP field. All point types
listed may not appear on any one 15' quadrangle.
Table 7 - Content of the Point Attribute Tables of structure layers
ITEM NAME WIDTH OUTPUT TYPE N. DEC AREA 4 12 F 3 not applicable (always 0) PERIMETER 4 12 F 3 not applicable (always 0) [coverage]# 4 5 B unique internal control number [coverage]-ID 4 5 B unique identification number PTTYPE 35 35 C point type DIP 3 3 I plunge or dip of linear or planar feature STRIKE 3 3 I azimuth of oriented symbolTable 8 - Point Types Recorded in the PTTYPE Field of structure layers
approx bedding bedding flat bedding foliation inclined cleavage ot bedding vert beddingThe orientation of the point symbol which represents the attitude is rotated to match the appropriate orientation indicated in the STRIKE field. The amount of rotation for each symbol is stored in the $ANGLE pseudo item.
Annotation -
Structure coverages contain annotation features. Annotation has meaning for
display purposes only and does not represent any real world object. Annotation
representing the value coded in the DIP field is placed near each point. The text
of the annotation, a character string identical to the DIP value, is stored in the
$TEXT pseudo item. No annotation is placed by attitude symbols which imply dip
inherently, e.g. horizontal or vertical bedding symbols.
Lines -
The lines (arcs) are recorded as strings of vectors and are described in the
arc attribute table (Table 3). They define fold axes and are recorded in the
LTYPE field according to the line types listed in Table 9. Not all structure
layers include fold axes, and all line types listed may not appear on any one 15'
quadrangle.
Table 9 - Line Types Recorded in the LTYPE Field of structure layers
f.a., anticline, certain f.a., anticline, concealed f.a., anticline, inferred, queried f.a., syncline, approx. located f.a., syncline, certain f.a., syncline, concealed f.a., syncline, inferredThe geologic line types are ALACARTE line types that correlate with the geologic line symbols in the ALACARTE line set GEOL61.LIN according to the ALACARTE lines lookup table (GEOL61.LUT). The designation "f.a." is used in ALACARTE to distinguish fold axes.
Annotation layers (xxx_ann) -
Annotation layers contain annotation and lines. Annotation layers do not include
geologic data; they are cartographic layers to be used for graphical display.
Annotation -
Annotation coverages contain the names of geologic units and faults. These
are placed and sized for display on a plotted version of the map at 1:62500 scale.
They are meant to be displayed with their associated leaders as some labels may
lie outside of the geologic unit they describe.
Lines -
The lines (arcs) are recorded as strings of vectors and are described in the
arc attribute table (Table 3). Lines on an annotation layer are leaders to unit
labels which lie outside of their geologic unit. The LTYPE field is left blank
for these layers.
Base layers (xxx_topo) -
Base layers contain lines.
Lines -
The lines (arcs) are recorded as strings of vectors and are described in the
arc attribute table (Table 3). The base layers are scans and have no attributes
(there is no LTYPE field in the arc attribute table of base layers).
Alteration Zone layers (xxx_alt) -
Alteration zone layers contain lines and areas.
Lines -
The lines (arcs) are recorded as strings of vectors and are described in the
arc attribute table (Table 3). They define the boundaries of alteration zones as
well as oil shale locations. These distinctions are recorded in the LTYPE field
according to the line types listed in Table 10. All line types listed may not
appear on any one 15' quadrangle.
Table 10 - Line Types Recorded in the LTYPE Field of alteration layers
alteration boundary oil shaleAreas -
Well layers (xxx_wel) -
Well layers contain points.
Points -
Points are described in the point attribute table (Table 7) Wells are
recorded in the PTTYPE field according to the point types listed in Table 11. The
DIP and STRIKE fields are not present in the point attribute table for well
layers.
Table 11 - Point Types Recorded in the PTTYPE Field of well layers
ONG CZ#1 (well identifier) REC CZ#1 (well identifier)ACKNOWLEDGMENTS
Compilation of the digital database depended on advice and assistance in the use of ALACARTE - ARC/INFO from T.T. Fitzgibbon, C.M. Wentworth, and G.A. Phelps.
REFERENCES CITED
Fitzgibbon, T.T., 1991, ALACARTE installation and system manual (version 1.0): U.S. Geological Survey, Open-File Report 91-587B. Fitzgibbon, T.T., and Wentworth, C.M., 1991, ALACARTE user interface - AML code and demonstration maps (version 1.0): U.S. Geological Survey, Open-File Report 91-587A. __ALACARTE 2.0 for ARC/INFO 6.x is available over Internet: http://wrgis.wr.usgs.gov/software/arc_stuff/alacarte/alacarte2.0.tar.Z Wentworth, C.M., and Fitzgibbon, T.T., 1991, ALACARTE user manual (version 1.0): U.S. Geological Survey, Open-File Report 91-587C.