Identification_Information: Citation: Citation_Information: Originator: L.S. Beard, R.E. Anderson, D.L. Block, R.G. Bohannon, R.J. Brady, S.B. Castor, E.M. Duebendorfer, J.E. Faulds, T.J. Felger, K.A. Howard, M.A. Kuntz, and V.S. Williams Publication_Date: 2007 Title: Preliminary Geologic Map of the Lake Mead 30' X 60' Quadrangle, Clark County, Nevada, and Mohave County, Arizona Edition: Version 1.0 Geospatial_Data_Presentation_Form: vector digital data (Personal Geodatabase) Series_Information: Series_Name: U.S. Geological Survey Open-File Report Issue_Identification: Open-File Report 2007-1010 Publication_Information: Publication_Place: Flagstaff, Arizona Publisher: U.S. Geological Survey Online_Linkage: http://pubs.usgs.gov/of/2007/1010/ Description: Abstract: This digital database, which was compiled from existing published and unpublished maps, as well as new mapping, contains geologic data used to produce the 1:100,000-scale Geologic Map of the Lake Mead 30' x 60' Quadrangle, Clark County, Nevada, and Mohave County, Arizona. The geologic features mapped as part of this project include: geologic contacts and faults, bedrock and surficial geologic units, structural data, fold axes, and dikes. The data were digitized and attributed from a variety of source maps. Refer to the Process Description section of this metadata report, and the accompanying map pamphlet for more information. Note: This metadata report provides an overview of the data content of this geodatabase. In addition, each feature class (except annotation feature classes) has a corresponding metadata report that should be referred to for additional, Data Quality and Entity Attribute information. Purpose: The geology of the Lake Mead 30' x 60' quadrangle was compiled for the U.S. Geological Survey's Las Vegas Urban Corridor Project and the National Parks Project, National Cooperative Geologic Mapping Program. Lake Mead, which occupies the northern part of the Lake Mead National Recreation Area (LAME), mostly lies within the Lake Mead quadrangle and provides recreation for about 9 million visitors annually The recreation area and surrounding Bureau of Land Management lands face increasing public pressure from rapid urban growth in the Las Vegas area to the west. This database and the accompanying map and pamphlet provide baseline earth science information that can be used in future studies of hazards, groundwater resources, mineral and aggregate resources, and of soils and vegetation. Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2007 Currentness_Reference: publication date Status: Progress: In work Maintenance_and_Update_Frequency: As needed Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -115.012700 East_Bounding_Coordinate: -113.978215 North_Bounding_Coordinate: 36.520963 South_Bounding_Coordinate: 35.979102 Keywords: Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: geologic map Theme_Keyword: geologic structure data Theme_Keyword: attitudes Theme_Keyword: strike and dip Theme_Keyword: bedding Theme_Keyword: foliation Theme_Keyword: joint Theme_Keyword: dike Theme_Keyword: fold axis Theme_Keyword: anticline Theme_Keyword: syncline Theme_Keyword: monocline Theme_Keyword: geologic contacts Theme_Keyword: geologic faults Theme_Keyword: fault Theme_Keyword: normal fault Theme_Keyword: low angle normal fault Theme_Keyword: strikeslip fault Theme_Keyword: thrust fault Theme_Keyword: geologic units Place: Place_Keyword_Thesaurus: None Place_Keyword: Lake Mead Place_Keyword: Mohave County Place_Keyword: Clark County Place_Keyword: Lower Colorado River Place_Keyword: Nevada Place_Keyword: Arizona Place_Keyword: USA Place_Keyword: Lake Mead National Recreation Area Place_Keyword: Las Vegas Access_Constraints: None Use_Constraints: Not for use at scales greater than 1:100,000. Any derivative products utilizing these datasets shall clearly indicate their source. If users modify the data in any way they are obligated to describe the types of modifications they have performed. User specifically agrees not to misrepresent these datasets, nor to imply that changes they made were approved by the U.S. Geological Survey. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: L. Sue Beard Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 2255 N. Gemini Dr. City: Flagstaff State_or_Province: AZ Postal_Code: 86001 Country: USA Contact_Voice_Telephone: 928-556-7196 Contact_Facsimile_Telephone: 928-556-7169 Contact_Electronic_Mail_Address: sbeard@usgs.gov Data_Set_Credit: This digital database was prepared by Debra Block, Tracey Felger, Michelle Harr, Melissa Aldrich, Anita Kaye, and Sue Priest. Technical review was provided by Angela Jayko and Ric Page of the U.S. Geological Survey. Digital review was provided by Scott Graham of the U.S. Geological Survey. Prepared in cooperation with the National Park Service. Native_Data_Set_Environment: ESRI ArcGIS 9.1, Personal Geodatabase Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: Geologic features were digitized and attributed, then cross-checked visually against the original source maps. Logical_Consistency_Report: This database has been reviewed and is considered to be error-free. All features have attributes. Each line segment has a length and directionality that is appropriate for the geologic feature it depicts. No sliver polygons are present. Completeness_Report: This database is considered complete. All geologic features relevant for depiction of the geology at 1:100,000-scale are included. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: These data are considered to be accurately located and within the National Map Accuracy Standard of +/-50 meters for 1:100,000-scale maps. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: Anderson, R.E. Publication_Date: 2003 Title: Geologic Map of the Callville Bay quadrangle, Nevada Series_Information: Series_Name: Nevada Bureau of Mines and Geology Map Issue_Identification: Map 139 Publication_Information: Publication_Place: Nevada Publisher: Nevada Bureau of Mines and Geology Online_Linkage: http://www.nbmg.unr.edu/dox/dox.htm#3 Source_Scale_Denominator: 24,000 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2003 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Anderson (2003) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Beard, L.S. Publication_Date: 1992 Title: Preliminary geologic map of the St. Thomas 7.5' quadrangle, Clark County, Nevada, and Mohave County, Arizona Series_Information: Series_Name: U.S. Geological Survey Open-File Report Issue_Identification: Open-File Report 92-326 Publication_Information: Publication_Place: Flagstaff, AZ Publisher: U.S. Geological Survey Source_Scale_Denominator: 24,000 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1992 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Beard (1992) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Beard, L.S., and Campagna, D.J. Publication_Date: 1991 Title: Preliminary geologic map of the Devils Throat quadrangle, Clark County, Nevada Series_Information: Series_Name: U.S. Geological Survey Open-File Report Issue_Identification: Open-File Report 91-132 Publication_Information: Publication_Place: Flagstaff, AZ Publisher: U.S. Geological Survey Source_Scale_Denominator: 24,000 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1991 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Beard and Campagna (1991) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Bell, J.W., and Smith, E.I. Publication_Date: 1980 Title: Geologic map of the Henderson quadrangle, Nevada Series_Information: Series_Name: Nevada Bureau of Mines and Geology Map Issue_Identification: Map 67 Publication_Information: Publication_Place: Nevada Publisher: Nevada Bureau of Mines and Geology Online_Linkage: http://www.nbmg.unr.edu/dox/dox.htm#3 Source_Scale_Denominator: 24,000 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1980 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Bell and Smith (1980) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Bohannon, R.G. Publication_Date: 1983 Title: Geologic map, tectonic map and structure sections of the Muddy and northern Black Mountains, Clark County, Nevada Series_Information: Series_Name: U.S. Geological Survey Miscellaneous Investigations Series Issue_Identification: I-1406 Publication_Information: Publication_Place: Denver, CO Publisher: U.S. Geological Survey Source_Scale_Denominator: 62,500 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1983 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Bohannon (1983) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Brady, R.J. Publication_Date: 1998 Title: The geology of the Gold Butte breakaway zone and the mechanical evolution of normal fault systems Series_Information: Series_Name: Ph.D. dissertation Issue_Identification: California Institute of Technology; Ph.D. dissertation Publication_Information: Publication_Place: California Publisher: California Institute of Technology Source_Scale_Denominator: 100,000 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1998 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Brady (1998) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Brady, Robert, Fryxell, Joan, and Wernicke, Brian Publication_Date: 2002 Title: Preliminary Geologic Map of the Iceberg Canyon Quadrangle, Clark County, Nevada and Mohave County, Arizona Series_Information: Series_Name: Nevada Bureau of Mines and Geology Open-File Report Issue_Identification: Open-File Report 03-18 Publication_Information: Publication_Place: Nevada Publisher: Nevada Bureau of Mines and Geology Online_Linkage: http://www.nbmg.unr.edu/dox/dox.htm#8 Source_Scale_Denominator: 24,000 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2002 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Brady and others (2002) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Campagna, D.J. Publication_Date: 1990 Title: The Lake Mead Fault System and the Las Vegas Valley Shear Zone: strike-slip faulting and associated deformation in the Basin and Range, southeastern Nevada Series_Information: Series_Name: Ph.D. dissertation Issue_Identification: Purdue University, Ph.D. dissertation Publication_Information: Publication_Place: West Lafayette, Indiana Publisher: Purdue University Source_Scale_Denominator: 1145 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1990 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Campagna (1990) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Cascadden, T.E. Publication_Date: 1991 Title: Style of volcanism and extensional tectonics in the eastern Basin and Range Province; northern Mohave County, Arizona Series_Information: Series_Name: M.S. thesis Issue_Identification: University of Nevada, Las Vegas; M.S. thesis Publication_Information: Publication_Place: Nevada, Las Vegas Publisher: University of Nevada, Las Vegas Source_Scale_Denominator: 62,500 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1991 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Cascadden (1991) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Castor, S.B., Faulds, J.E., dePaolo, C.M., and Rowland, S.M. Publication_Date: 2000 Title: Geologic map of the Frenchman Mountain quadrangle, Nevada Series_Information: Series_Name: Nevada Bureau of Mines and Geology Map Issue_Identification: Map 127 Publication_Information: Publication_Place: Nevada Publisher: Nevada Bureau of Mines and Geology Online_Linkage: http://www.nbmg.unr.edu/dox/dox.htm#3 Source_Scale_Denominator: 24,000 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Castor and others (2000) Source_Contribution: Geologic mappping Source_Information: Source_Citation: Citation_Information: Originator: Duebendorfer, E.M. Publication_Date: 2003 Title: Geologic map of the Government Wash quadrangle, Nevada Series_Information: Series_Name: Nevada Bureau of Mines and Geology Map Issue_Identification: Map 140 Publication_Information: Publication_Place: Nevada Publisher: Nevada Bureau of Mines and Geology Online_Linkage: http://www.nbmg.unr.edu/dox/dox.htm#3 Source_Scale_Denominator: 24,000 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2003 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Duebendorfer (2003) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Duebendorfer, E.M., Sewall, A.J., and Smith, E.I. Publication_Date: 1990 Title: The Saddle Island detachment; an evolving shear zone in the Lake Mead area, Nevada: in Wernicke, B.P., ed., Basin and Range extensional tectonics near the latitude of Las Vegas, Nevada Series_Information: Series_Name: Geological Society of America Memoir Issue_Identification: 176, p. 77-97 Publication_Information: Publication_Place: Boulder, Colorado Publisher: Geological Society of America Source_Scale_Denominator: 6,000 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1990 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Duebendorfer and others (1990) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Eschner, Edward Publication_Date: 1989 Title: The geology and structural significance of the Arch Mountain area, northern Black Mountains, Mohave County, Arizona Series_Information: Series_Name: M.S. Thesis Issue_Identification: University of Nevada, Las Vegas; M.S. Thesis Publication_Information: Publication_Place: Nevada, Las Vegas Publisher: University of Nevada, Las Vegas Source_Scale_Denominator: 24,000 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1989 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Eschner (1989) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Feuerbach, Daniel Lee Publication_Date: 1986 Title: Geology of the Wilson Ridge pluton; a Mid-Miocene quartz monzonite intrusion in the northern Black Mountains, Mohave County, Arizona and Clark County, Nevada Series_Information: Series_Name: M.S. Thesis Issue_Identification: University of Nevada, Las Vegas; M.S. Thesis Publication_Information: Publication_Place: Nevada, Las Vegas Publisher: University of Nevada, Las Vegas Source_Scale_Denominator: 24,000 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1986 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Feuerbach (1986) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Fryxell, J., Salton, G., Selverstone, J., and Wernicke, B. Publication_Date: 1992 Title: Gold Butte crustal section, South Virgin Mountains, Nevada Series_Information: Series_Name: Tectonics Issue_Identification: volume 11, p. 1099-1120 Publication_Information: Publication_Place: Washington, DC Publisher: American Geophysical Union Source_Scale_Denominator: 62,500 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1992 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Fryxell and others (1992) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Howard, K.A., Hook, S.J., Phelps, G.A., and Block, D.L. Publication_Date: 2003 Title: Geologic map of the Hiller Mountains 7.5' quadrangle, Clark County, Nevada and Mohave County, Arizona Series_Information: Series_Name: Nevada Bureau of Mines and Geology Map Issue_Identification: Map 137 Publication_Information: Publication_Place: Nevada Publisher: Nevada Bureau of Mines and Geology Online_Linkage: http://www.nbmg.unr.edu/dox/dox.htm#3 Source_Scale_Denominator: 24,000 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2003 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Howard and others (2003) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Lucchitta, Ivo Publication_Date: 1966 Title: Cenozoic geology of the upper Lake Mead area adjacent to the Grand Wash Cliffs, Arizona Series_Information: Series_Name: Ph.D. dissertation Issue_Identification: Pennsylvania State University; Ph.D. dissertation Publication_Information: Publication_Place: Pennsylvania Publisher: Pennsylvania State University Source_Scale_Denominator: 63,360 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1966 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Lucchitta (1966) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Mills, James G. Publication_Date: 1994 Title: Geologic Map of the Hoover Dam Quadrangle, Arizona and Nevada Series_Information: Series_Name: Nevada Bureau of Mines and Geology Map Issue_Identification: Map 102 Publication_Information: Publication_Place: Nevada Publisher: Nevada Bureau of Mines and Geology Online_Linkage: http://www.nbmg.unr.edu/dox/dox.htm#3 Source_Scale_Denominator: 24,000 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1994 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Mills (1994) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Naumann, T.R. Publication_Date: 1987 Title: Geology of the central Boulder Canyon quadrangle, Clark County, Nevada Series_Information: Series_Name: M.S. thesis Issue_Identification: University of Nevada, Las Vegas; M.S. thesis Publication_Information: Publication_Place: Nevada, Las Vegas Publisher: University of Nevada, Las Vegas Source_Scale_Denominator: 24,000 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1987 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Naumann (1987) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Scott, A. J. Publication_Date: 1988 Title: The Muddy Creek Formation: depositional environment, provenance, and tectonic significance in the western Lake Mead area, Nevada and Arizona Series_Information: Series_Name: M.S. thesis Issue_Identification: University of Nevada, Las Vegas; M.S. thesis Publication_Information: Publication_Place: Nevada, Las Vegas Publisher: University of Nevada, Las Vegas Source_Scale_Denominator: 12,000 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1988 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Scott (1988) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Smith, E.I. Publication_Date: 1984 Title: Geologic map of the Boulder Beach quadrangle, Nevada Series_Information: Series_Name: Nevada Bureau of Mines and Geology Map Issue_Identification: Map 81 Publication_Information: Publication_Place: Nevada Publisher: Nevada Bureau of Mines and Geology Online_Linkage: http://www.nbmg.unr.edu/dox/dox.htm#3 Source_Scale_Denominator: 24,000 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1984 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Smith (1984) Source_Contribution: Geologic map Source_Information: Source_Citation: Citation_Information: Originator: Thompson, K.G. Publication_Date: 1985 Title: Stratigraphy and petrology of the Hamblin-Cleopatra Volcano, Clark County, Nevada Series_Information: Series_Name: M.S. thesis Issue_Identification: University of Texas, Austin, Austin, Texas; M.S. thesis Publication_Information: Publication_Place: Austin, Texas Publisher: University of Texas, Austin Source_Scale_Denominator: 11,000 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1985 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Thompson (1985) Source_Contribution: Geologic mapping Source_Information: Source_Citation: Citation_Information: Originator: Wallace, M.A., Faulds, J.E., and Brady, R.J. Publication_Date: 2006 Title: Geologic map of the Meadview North quadrangle, Arizona and Nevada Series_Information: Series_Name: Nevada Bureau of Mines and Geology Map Issue_Identification: Map 154 Publication_Information: Publication_Place: Nevada Publisher: Nevada Bureau of Mines and Geology Online_Linkage: http://www.nbmg.unr.edu/dox/dox.htm#3 Source_Scale_Denominator: 24,000 Type_of_Source_Media: Paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2006 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Wallace and others (2006) Source_Contribution: Geologic mapping Process_Step: Process_Description: The geology was compiled from many sources, both published and unpublished, and includes significant new mapping that was conducted specifically for this project. Some of the published sources were reinterpreted or modified based on field checking. Map sources include 1:24,000-scale maps published by the Nevada Bureau of Mines (Anderson, 2003, Bell and Smith, 1980, Brady and others, 2002, Castor and others, 2000, Duebendorfer, 2003, Howard and others, 2003, Mills, 1994, Smith, 1984, Wallace and others, 2006) and the U.S. Geological Survey (Beard and Campagna, 1991, Beard, 1992). About one-third of the map was compiled and modified from the 1:62,500 scale map of the Muddy and Northern Black Mountains (Bohannon, 1983). The remainder of the map involved new mapping at scales from 1:24000 to 1:100,000-scale; in addition, mapping published in Fryxell and others (1992) was compiled and modified by new mapping. A few local thesis maps were also used to guide compilation in the southwestern part of the quadrangle (Cascadden, 1991, Eschner, 1989, Feuerbach, 1986, Naumann, 1987, Scott, 1988, and Thompson, 1985). Geochronologic data from published sources, as well as preliminary unpublished 40Ar/39Ar ages that were obtained for this report have been used to refine the ages of formal Tertiary stratigraphy and define new informal Tertiary sedimentary and volcanic units. Refer to the map pamphlet for details. Digital compilation of this map began in ARC/INFO version 7.1.2 and was completed in ArcGIS 9.1. Geologic features were compiled originally as coverages into 7.5-minute quadrangle 'blocks', which then were appended together as a single 1:100,000-scale database. The map was then generalized in certain areas that had been compiled from more detailed 7.5-minute quadrangles. Because of this approach, some areas of the final map may show relatively more detail than others. Source materials ranged in scale from 1:24,000 to 1:100,000, and included published maps and unpublished field sheets. These source maps were either scanned using an Optronics 5040 scanner with a resolution of 508dpi/50microns, or digitized in projection units using an Altek AC-32 digitizer. The scanned images were vectorized and transformed from scanner coordinates to projection coordinates with digital tics placed by hand at quadrangle corners. Coverages were edited and attributed interactively in Arcedit using custom menus. Snapping tolerances were generally set at 20 meters with grain and weed at 5 meters for 1:24,000 scale maps, 35 meters with grain and weed at 15 meters for 1:62,500 scale maps, and 45 meters with grain and weed at 20 meters for 1:100,000 scale maps. Faults are digitized with the down-thrown block, if known, on the 'right side' of the line. The 'right' and 'left' sides of a line are determined from 'starting' at the line's 'from node' and moving to the line's end or 'to node'. The coverages subsequently were converted into ArcGIS Personal Geodatabase feature classes, and final editing took place in ArcMap. The ArcCatalog process 'Create new polygon feature class from lines and points' was used to create geologic unit polygons (lmglg_poly_100k) from geologic contacts and faults (lmglg_arc) and geologic unit labels (lmglg_pt). Each feature class was symbolized based on attributes and plotted at 1:24,000-scale and then 1:100,000-scale and compared to the source maps for correctness and completeness. Process_Date: 1996-2007 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Tracey J. Felger Contact_Organization: U.S. Geological Survey Contact_Position: Geologist/GIS Specialist Contact_Address: Address_Type: mailing and physical address Address: 2255 N. Gemini Dr. City: Flagstaff State_or_Province: AZ Postal_Code: 86001 Country: USA Contact_Voice_Telephone: 928-556-7517 Contact_Facsimile_Telephone: 928-556-7169 Contact_Electronic_Mail_Address: tfelger@usgs.gov Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Vector Point_and_Vector_Object_Information: SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: String Point_and_Vector_Object_Count: 31767 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: Entity point Point_and_Vector_Object_Count: 11201 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: Entity point Point_and_Vector_Object_Count: 1136 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: String Point_and_Vector_Object_Count: 305 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: String Point_and_Vector_Object_Count: 83 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: G-polygon Point_and_Vector_Object_Count: 11201 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 11 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.999600 Longitude_of_Central_Meridian: -117.000000 Latitude_of_Projection_Origin: 0.000000 False_Easting: 500000.000000 False_Northing: 0.000000 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: coordinate pair Coordinate_Representation: Abscissa_Resolution: 0.000128 Ordinate_Resolution: 0.000128 Planar_Distance_Units: meters Geodetic_Model: Horizontal_Datum_Name: North American Datum of 1927 Ellipsoid_Name: Clarke 1866 Semi-major_Axis: 6378206.400000 Denominator_of_Flattening_Ratio: 294.978698 Vertical_Coordinate_System_Definition: Altitude_System_Definition: Altitude_Resolution: 0.000010 Altitude_Encoding_Method: Explicit elevation coordinate included with horizontal coordinates Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: lmglg_arc (Personal Geodatabase, Line Feature Class) Entity_Type_Definition: Geologic contacts and faults Entity_Type_Definition_Source: User defined Detailed_Description: Entity_Type: Entity_Type_Label: lmglg_pt (Personal Geodatabase, Point Feature Class) Entity_Type_Definition: Geologic unit Labels Entity_Type_Definition_Source: User defined Detailed_Description: Entity_Type: Entity_Type_Label: lmatd (Personal Geodatabase, Point Feature Class) Entity_Type_Definition: Geologic structure data (attitudes, foliation, joints) Entity_Type_Definition_Source: User defined Detailed_Description: Entity_Type: Entity_Type_Label: lmdke (Personal Geodatabase, Line Feature Class) Entity_Type_Definition: Intrusive dikes Entity_Type_Definition_Source: User defined Detailed_Description: Entity_Type: Entity_Type_Label: lmfld (Personal Geodatabase, Line Feature Class) Entity_Type_Definition: Fold axes (synclines, anticlines, monoclines) Entity_Type_Definition_Source: User defined Detailed_Description: Entity_Type: Entity_Type_Label: lmatd_100kAnno (Personal Geodatabase, Annotation Feature Class) Entity_Type_Definition: Feature-linked annotation for display and plotting dip values at 1:100,000-scale Entity_Type_Definition_Source: User defined Detailed_Description: Entity_Type: Entity_Type_Label: lmglg_100KAnno (Personal Geodatabase, Annotation Feature Class) Entity_Type_Definition: Feature-linked annotation for display and plotting geologic unit labels at 1:100,000-scale Entity_Type_Definition_Source: User defined Detailed_Description: Entity_Type: Entity_Type_Label: lmglg_poly_100k (Personal Geodatabase, Polygon Feature Class) Entity_Type_Definition: Geologic units Entity_Type_Definition_Source: User defined Detailed_Description: Entity_Type: Entity_Type_Label: lmatd_100kAnno (Personal Geodatabase, Relationship Class) Entity_Type_Definition: Establishes link between feature-linked annotation (lmatd_100kanno) and values stored in the DIP field in the structure data (lmatd) Entity_Type_Definition_Source: User defined Detailed_Description: Entity_Type: Entity_Type_Label: lmglg_100KAnno (Personal Geodatabase, Relationship Class) Entity_Type_Definition: Establishes link between feature-linked annotation (lmglg_100kanno) and values stored in the GEOFNT100K field in the structure data (lmglg_pt) Entity_Type_Definition_Source: User defined Detailed_Description: Entity_Type: Entity_Type_Label: lmlmu100k (Personal Geodatabase, Table) Entity_Type_Definition: List of 1:100,000-scale geologic map units Entity_Type_Definition_Source: User defined Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Information Services Contact_Address: Address_Type: mailing address Address: Box 25286 Denver Federal Center City: Denver State_or_Province: CO Postal_Code: 80225 Country: USA Contact_Voice_Telephone: 1-888-ASK-USGS Contact_Electronic_Mail_Address: ask@usgs.gov Resource_Description: Downloadable Data Distribution_Liability: The U.S. Geological Survey (USGS) provides these geographic data "as is." The USGS makes no guarantee or warranty concerning the accuracy of information contained in the geographic data. The USGS further makes no warranties, either expressed or implied as to any other matter whatsoever, including, without limitation, the condition of the product, or its fitness for any particular purpose. The burden for determining fitness for use lies entirely with the user. Although these data have been processed successfully on computers at the USGS, no warranty, expressed or implied, is made by the USGS regarding the use of these data on any other system, nor does the fact of distribution constitute or imply any such warranty. In no event shall the USGS have any liability whatsoever for payment of any consequential, incidental, indirect, special, or tort damages of any kind, including, but not limited to, any loss of profits arising out of use of or reliance on the geographic data or arising out of delivery, installation, operation, or support by USGS. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: ArcGIS Personal Geodatabase Format_Version_Number: 9.1 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://pubs.usgs.gov/of/2007/1010/ Fees: None Metadata_Reference_Information: Metadata_Date: 20060901 Metadata_Review_Date: 20070115 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Tracey J. Felger Contact_Organization: U.S. Geological Survey Contact_Position: Geologist/GIS Specialist Contact_Address: Address_Type: mailing and physical address Address: 2255 N. Gemini Dr. City: Flagstaff State_or_Province: AZ Postal_Code: 86001 Country: USA Contact_Voice_Telephone: 928-556-7517 Contact_Facsimile_Telephone: 928-556-7169 Contact_Electronic_Mail_Address: tfelger@usgs.gov Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Time_Convention: local time Metadata_Extensions: Online_Linkage: http://www.esri.com/metadata/esriprof80.html Profile_Name: ESRI Metadata Profile