This edition of the Geologic Map of California was prepared in recognition of the California Geological Survey's 150th Anniversary. It is an all-digital product built on the original compilation of C.W. Jennings published in 1977, with some additions and modifications. The Geologic Map of California presents an overview of the geology and structure of the state. It represents the geologic features that one would find on a visit to any locality in the state. The restraints of scale limit the detail that can be shown, but the most important geologic features are portrayed. The distribution of the major rock types and the major structural elements are shown with sufficient detail to be useful for many purposes. Please see the map pamphlet (included in this digital package as a PDF document) for further information.
A GIS database of geologic units and structural features in California, with lithology, age, data structure, and format written and arranged just like the other states.
description: The Digital Geologic Map of the Marin Headlands and Point Reyes Areas, California is composed of GIS data layers complete with ArcMap 9.3 layer (.LYR) files, two ancillary GIS tables, a Map PDF document with ancillary map text, figures and tables, a FGDC metadata record and a 9.3 ArcMap (.MXD) Document that displays the digital map in 9.3 ArcGIS. The data were completed as a component of the Geologic Resources Inventory (GRI) program, a National Park Service (NPS) Inventory and Monitoring (I&M) funded program that is administered by the NPS Geologic Resources Division (GRD). Source geologic maps and data used to complete this GRI digital dataset were provided by the following: USGS and California Geological Survey. Detailed information concerning the sources used and their contribution the GRI product are listed in the Source Citation sections(s) of this metadata record (mhpr_metadata.txt; available at http://nrdata.nps.gov/goga/nrdata/geology/gis/mhpr_metadata.xml). All GIS and ancillary tables were produced as per the NPS GRI Geology-GIS Geodatabase Data Model v. 2.1. (available at: http://science.nature.nps.gov/im/inventory/geology/GeologyGISDataModel.cfm). The GIS data is available as a 9.3 personal geodatabase (mhpr_geology.mdb), and as shapefile (.SHP) and DBASEIV (.DBF) table files. The GIS data projection is NAD83, UTM Zone 10N. That data is within the area of interest of Golden Gate National Recreation Area, Point Reyes National Seashore and Muir Woods National Monument.; abstract: The Digital Geologic Map of the Marin Headlands and Point Reyes Areas, California is composed of GIS data layers complete with ArcMap 9.3 layer (.LYR) files, two ancillary GIS tables, a Map PDF document with ancillary map text, figures and tables, a FGDC metadata record and a 9.3 ArcMap (.MXD) Document that displays the digital map in 9.3 ArcGIS. The data were completed as a component of the Geologic Resources Inventory (GRI) program, a National Park Service (NPS) Inventory and Monitoring (I&M) funded program that is administered by the NPS Geologic Resources Division (GRD). Source geologic maps and data used to complete this GRI digital dataset were provided by the following: USGS and California Geological Survey. Detailed information concerning the sources used and their contribution the GRI product are listed in the Source Citation sections(s) of this metadata record (mhpr_metadata.txt; available at http://nrdata.nps.gov/goga/nrdata/geology/gis/mhpr_metadata.xml). All GIS and ancillary tables were produced as per the NPS GRI Geology-GIS Geodatabase Data Model v. 2.1. (available at: http://science.nature.nps.gov/im/inventory/geology/GeologyGISDataModel.cfm). The GIS data is available as a 9.3 personal geodatabase (mhpr_geology.mdb), and as shapefile (.SHP) and DBASEIV (.DBF) table files. The GIS data projection is NAD83, UTM Zone 10N. That data is within the area of interest of Golden Gate National Recreation Area, Point Reyes National Seashore and Muir Woods National Monument.
The Digital Geologic-GIS Map of Pinnacles National Park and Vicinity, California is composed of GIS data layers and GIS tables, and is available in the following GRI-supported GIS data formats: 1.) a 10.1 file geodatabase (pinn_geology.gdb), a 2.) Open Geospatial Consortium (OGC) geopackage, and 3.) 2.2 KMZ/KML file for use in Google Earth, however, this format version of the map is limited in data layers presented and in access to GRI ancillary table information. The file geodatabase format is supported with a 1.) ArcGIS Pro map file (.mapx) file (pinn_geology.mapx) and individual Pro layer (.lyrx) files (for each GIS data layer), as well as with a 2.) 10.1 ArcMap (.mxd) map document (pinn_geology.mxd) and individual 10.1 layer (.lyr) files (for each GIS data layer). The OGC geopackage is supported with a QGIS project (.qgz) file. Upon request, the GIS data is also available in ESRI 10.1 shapefile format. Contact Stephanie O'Meara (see contact information below) to acquire the GIS data in these GIS data formats. In addition to the GIS data and supporting GIS files, three additional files comprise a GRI digital geologic-GIS dataset or map: 1.) A GIS readme file (pinn_geology_gis_readme.pdf), 2.) the GRI ancillary map information document (.pdf) file (pinn_geology.pdf) which contains geologic unit descriptions, as well as other ancillary map information and graphics from the source map(s) used by the GRI in the production of the GRI digital geologic-GIS data for the park, and 3.) a user-friendly FAQ PDF version of the metadata (pinn_geology_metadata_faq.pdf). Please read the pinn_geology_gis_readme.pdf for information pertaining to the proper extraction of the GIS data and other map files. Google Earth software is available for free at: https://www.google.com/earth/versions/. QGIS software is available for free at: https://www.qgis.org/en/site/. Users are encouraged to only use the Google Earth data for basic visualization, and to use the GIS data for any type of data analysis or investigation. The data were completed as a component of the Geologic Resources Inventory (GRI) program, a National Park Service (NPS) Inventory and Monitoring (I&M) Division funded program that is administered by the NPS Geologic Resources Division (GRD). For a complete listing of GRI products visit the GRI publications webpage: For a complete listing of GRI products visit the GRI publications webpage: https://www.nps.gov/subjects/geology/geologic-resources-inventory-products.htm. For more information about the Geologic Resources Inventory Program visit the GRI webpage: https://www.nps.gov/subjects/geology/gri,htm. At the bottom of that webpage is a "Contact Us" link if you need additional information. You may also directly contact the program coordinator, Jason Kenworthy (jason_kenworthy@nps.gov). Source geologic maps and data used to complete this GRI digital dataset were provided by the following: California Geological Survey. Detailed information concerning the sources used and their contribution the GRI product are listed in the Source Citation section(s) of this metadata record (pinn_geology_metadata.txt or pinn_geology_metadata_faq.pdf). Users of this data are cautioned about the locational accuracy of features within this dataset. Based on the source map scale of 1:100,000 and United States National Map Accuracy Standards features are within (horizontally) 50.8 meters or 166.7 feet of their actual location as presented by this dataset. Users of this data should thus not assume the location of features is exactly where they are portrayed in Google Earth, ArcGIS, QGIS or other software used to display this dataset. All GIS and ancillary tables were produced as per the NPS GRI Geology-GIS Geodatabase Data Model v. 2.3. (available at: https://www.nps.gov/articles/gri-geodatabase-model.htm).
This geologic map database is a reproduction of U.S. Geological Survey Miscellaneous Investigations Map I–2362: “Geologic Map and Structure Sections of the Clear Lake Volcanics, Northern California” (Hearn, Donnelly-Nolan, and Goff, 1995). The database consists of a geologic map, three structural cross sections and a table of petrographic data for each map unit by mineral type, abundance, and size. The Clear Lake Volcanics are in the California Coast Ranges about 150 km north of San Francisco. This Quaternary volcanic field has erupted intermittently since 2.1 million years ago. This volcanic field is considered a high-threat volcanic system (Ewert and others, 2005). The adjacent Geysers geothermal field, the largest power-producing geothermal field in the world, is powered by the magmatic heat source for the volcanic field. The geology of parts of the area underlain by the Cache Formation is based on mapping by Rymer (1981); the geology of parts of the areas underlain by the Sonoma Volcanics, Franciscan assemblage, and Great Valley sequence is based on mapping by McLaughlin (1978). Volcanic compositional map units are basalt, basaltic andesite, andesite, dacite, rhyodacite, and rhyolite, based on SiO2 content. Most ages are potassium-argon (K/Ar) ages determined for whole-rock samples and mineral separates by Donnelly-Nolan and others (1981), unless otherwise noted. A few ages are carbon-14 ages or were estimated from geologic relationships. Magnetic polarities are from Mankinen and others (1978; 1981) or were determined in the field by B.C. Hearn, Jr., using a portable fluxgate magnetometer. Thickness for most units is estimated from topographic relief except where drill-hole data were available. This database does not reproduce all elements of the original publication. Omissions include the chart and figures showing erupted volumes of different lava types through time, and the chart and diagram for the correlation of map units. Users of this database are highly encouraged to cross reference this database with the original publication.
Attribution 4.0 (CC BY 4.0)https://creativecommons.org/licenses/by/4.0/
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abstract: All the individual maps from the Geologic Atlas of California and the Regional Geologic map series have been georeferenced for display in a GIS (and viewable online at http://www.conservation.ca.gov/cgs/information/geologic_mapping/Pages/googlemaps.aspx). The purpose of this index is to help users identify the extent and locate geologic maps from the California Geological Survey (CGS).Index map showing the areas covered by the individual sheets of the Geologic Atlas and the Regional Geologic map series from the CGS.CGS Geologic Maps Index
The Digital Geologic Map of Cabrillo National Monument and vicinity, California is composed of GIS data layers complete with ArcMap 9.3 layer (.LYR) files, two ancillary GIS tables, a Map PDF document with ancillary map text, figures and tables, a FGDC metadata record and a 9.3 ArcMap (.MXD) Document that displays the digital map in 9.3 ArcGIS. The data were completed as a component of the Geologic Resources Inventory (GRI) program, a National Park Service (NPS) Inventory and Monitoring (I&M) funded program that is administered by the NPS Geologic Resources Division (GRD). Source geologic maps and data used to complete this GRI digital dataset were provided by the following: California Geological Survey. Detailed information concerning the sources used and their contribution the GRI product are listed in the Source Citation sections(s) of this metadata record (cabr_metadata.txt; available at http://nrdata.nps.gov/cabr/nrdata/geology/gis/cabr_metadata.xml). All GIS and ancillary tables were produced as per the NPS GRI Geology-GIS Geodatabase Data Model v. 2.1. (available at: http://science.nature.nps.gov/im/inventory/geology/GeologyGISDataModel.cfm). The GIS data is available as a 9.3 personal geodatabase (cabr_geology.mdb), and as shapefile (.SHP) and DBASEIV (.DBF) table files. The GIS data projection is NAD83, UTM Zone 11N. That data is within the area of interest of Cabrillo National Monument.
This Open-File report is a digital geologic map database. This digital map database is compiled from previously published sources combined with some new mapping and modifications in nomenclature. The geologic map database delineates map units that are identified by general age and lithology following the stratigraphic nomenclature of the U. S. Geological Survey.
description: The Unpublished Digital Geologic Map of Santa Monica Mountains National Recreation Area and Vicinity, California is composed of GIS data layers and GIS tables in a 10.1 file geodatabase (samo_geology.gdb), a 10.1 ArcMap (.MXD) map document (samo_geology.mxd), individual 10.1 layer (.LYR) files for each GIS data layer, an ancillary map information (.PDF) document (samo_geology.pdf) which contains source map unit descriptions, as well as other source map text, figures and tables, metadata in FGDC text (.TXT) and FAQ (.HTML) formats, and a GIS readme file (samo_gis_readme.pdf). Please read the samo_gis_readme.pdf for information pertaining to the proper extraction of the file geodatabase and other map files. To request GIS data in ESRI 10.1 shapefile format contact Stephanie OMeara (stephanie.omeara@colostate.edu; see contact information below). The data is also available as a 2.2 KMZ/KML file for use in Google Earth, however, this format version of the map is limited in data layers presented and in access to GRI ancillary table information. Google Earth software is available for free at: http://www.google.com/earth/index.html. Users are encouraged to only use the Google Earth data for basic visualization, and to use the GIS data for any type of data analysis or investigation. The data were completed as a component of the Geologic Resources Inventory (GRI) program, a National Park Service (NPS) Inventory and Monitoring (I&M) Division funded program that is administered by the NPS Geologic Resources Division (GRD). Source geologic maps and data used to complete this GRI digital dataset were provided by the following: California Geological Survey. Detailed information concerning the sources used and their contribution the GRI product are listed in the Source Citation section(s) of this metadata record (samo_metadata_faq.html; available at http://nrdata.nps.gov/geology/gri_data/gis/samo/samo_metadata_faq.html). Users of this data are cautioned about the locational accuracy of features within this dataset. Based on the source map scale of 1:100,000 and United States National Map Accuracy Standards features are within (horizontally) 50.8 meters or 166.7 feet of their actual location as presented by this dataset. Users of this data should thus not assume the location of features is exactly where they are portrayed in Google Earth, ArcGIS or other software used to display this dataset. All GIS and ancillary tables were produced as per the NPS GRI Geology-GIS Geodatabase Data Model v. 2.3. (available at: http://science.nature.nps.gov/im/inventory/geology/GeologyGISDataModel.cfm). The GIS data projection is NAD83, UTM Zone 11N, however, for the KML/KMZ format the data is projected upon export to WGS84 Geographic, the native coordinate system used by Google Earth. The data is within the area of interest of Santa Monica Mountains National Recreation Area.; abstract: The Unpublished Digital Geologic Map of Santa Monica Mountains National Recreation Area and Vicinity, California is composed of GIS data layers and GIS tables in a 10.1 file geodatabase (samo_geology.gdb), a 10.1 ArcMap (.MXD) map document (samo_geology.mxd), individual 10.1 layer (.LYR) files for each GIS data layer, an ancillary map information (.PDF) document (samo_geology.pdf) which contains source map unit descriptions, as well as other source map text, figures and tables, metadata in FGDC text (.TXT) and FAQ (.HTML) formats, and a GIS readme file (samo_gis_readme.pdf). Please read the samo_gis_readme.pdf for information pertaining to the proper extraction of the file geodatabase and other map files. To request GIS data in ESRI 10.1 shapefile format contact Stephanie OMeara (stephanie.omeara@colostate.edu; see contact information below). The data is also available as a 2.2 KMZ/KML file for use in Google Earth, however, this format version of the map is limited in data layers presented and in access to GRI ancillary table information. Google Earth software is available for free at: http://www.google.com/earth/index.html. Users are encouraged to only use the Google Earth data for basic visualization, and to use the GIS data for any type of data analysis or investigation. The data were completed as a component of the Geologic Resources Inventory (GRI) program, a National Park Service (NPS) Inventory and Monitoring (I&M) Division funded program that is administered by the NPS Geologic Resources Division (GRD). Source geologic maps and data used to complete this GRI digital dataset were provided by the following: California Geological Survey. Detailed information concerning the sources used and their contribution the GRI product are listed in the Source Citation section(s) of this metadata record (samo_metadata_faq.html; available at http://nrdata.nps.gov/geology/gri_data/gis/samo/samo_metadata_faq.html). Users of this data are cautioned about the locational accuracy of features within this dataset. Based on the source map scale of 1:100,000 and United States National Map Accuracy Standards features are within (horizontally) 50.8 meters or 166.7 feet of their actual location as presented by this dataset. Users of this data should thus not assume the location of features is exactly where they are portrayed in Google Earth, ArcGIS or other software used to display this dataset. All GIS and ancillary tables were produced as per the NPS GRI Geology-GIS Geodatabase Data Model v. 2.3. (available at: http://science.nature.nps.gov/im/inventory/geology/GeologyGISDataModel.cfm). The GIS data projection is NAD83, UTM Zone 11N, however, for the KML/KMZ format the data is projected upon export to WGS84 Geographic, the native coordinate system used by Google Earth. The data is within the area of interest of Santa Monica Mountains National Recreation Area.
The Blythe 30' x 60' quadrangle in southeastern California and southwestern Arizona displays complex geology that includes Mesozoic contractional deformation, metamorphism, and magmatism and Cenozoic extensional deformation and magmatism. The scope of the present map is limited to bedrock units of Miocene and older age because the younger deposits have not been mapped in sufficient detail across the quadrangle to support a systematic compilation. Mapping and topical studies by previous investigators (refer to accompanying pamphlet) resulted in recognition of the following regionally significant geologic features: (1) variably metamorphosed and deformed Paleozoic to early Mesozoic sedimentary rocks stratigraphically correlative with cratonal platform strata of the Colorado Plateau region; (2) Jurassic plutonic and volcanic rocks; (3) thick sequences of moderately to weakly metamorphosed sedimentary rocks of the Jurassic to Cretaceous McCoy Basin; (4) ductile folds and faults of the Late Cretaceous Maria Belt; and (5) Miocene detachment faults in the Big Maria and Plomosa Mountains. A major recent discovery is the recognition of the Late Cretaceous to Paleogene Orocopia Schist structurally below undated gneiss in the northern Plomosa Mountains. This northernmost outcrop area of Orocopia Schist yet found in western Arizona demonstrates that the entire Blythe quadrangle likely is underlain by this extensive, tectonically underplated subduction complex. In addition, post-middle Miocene transtensional deformation has been documented in the northern La Posa Plain, including recognition of left-lateral motion on two northeast-striking faults in the northern Plomosa Mountains and at Mesquite Mountain.
The Digital Geologic Map of Golden Gate National Recreation Area and Vicinity, California is composed of GIS data layers complete with ArcMap 9.3 layer (.LYR) files, two ancillary GIS tables, a Map PDF document with ancillary map text, figures and tables, a FGDC metadata record and a 9.3 ArcMap (.MXD) Document that displays the digital map in 9.3 ArcGIS. The data were completed as a component of the Geologic Resources Inventory (GRI) program, a National Park Service (NPS) Inventory and Monitoring (I&M) funded program that is administered by the NPS Geologic Resources Division (GRD). Source geologic maps and data used to complete this GRI digital dataset were provided by the following: USGS and California Geological Survey. Detailed information concerning the sources used and their contribution the GRI product are listed in the Source Citation sections(s) of this metadata record (goga_metadata.txt; available at http://nrdata.nps.gov/goga/nrdata/geology/gis/goga_metadata.xml). All GIS and ancillary tables were produced as per the NPS GRI Geology-GIS Geodatabase Data Model v. 2.1. (available at: http://science.nature.nps.gov/im/inventory/geology/GeologyGISDataModel.cfm). The GIS data is available as a 9.3 personal geodatabase (goga_geology.mdb), and as shapefile (.SHP) and DBASEIV (.DBF) table files. The GIS data projection is NAD83, UTM Zone 10N. That data is within the area of interest of Golden Gate National Recreation Area, Point Reyes National Seashore, Muir Woods National Monument, Fort Point National Historic Site, Rosie the Riveter National Historical Park and San Francisco Maritime National Historical Park.
This digital map database, which is compiled from previously published and unpublished sources combined with new mapping, represents the general distribution and identity of bedrock in Contra Costa County, California.
U.S. Government Workshttps://www.usa.gov/government-works
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This geodatabase contains all of the map information used to publish the Surficial Geologic Map of the Owlshead Mountains 30’ X 60’ Quadrangle,Inyo and San Bernardino Counties, California: U.S. Geological Survey Scientific Investigations Map SIM-3496. The geodatabase and associated map delineate primarily surficial geology and neotectonics structure across the entire extent of this quadrangle, which includes 32 complete 7.5’ quadrangles located in the Owlshead Mountains, southern Death Valley, and adjoining basins and highlands in the southwestern section of Inyo County and the northeastern part of San Bernardino County in eastern California. The datasets contained in this Scientific Investigation Map describe the surficial geology within the entire map area of the Owlshead Mountains (OM) 30' X 60' Quadrangle. The geodatabase and associated geologic map delineate primarily surficial geology and neotectonics structure across the entire extent of this quadrangle, which includes 32 ...
U.S. Government Workshttps://www.usa.gov/government-works
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A database of geologic map of Lassen Volcanic National Park as described in the original abstract: The geologic map of Lassen Volcanic National Park (LVNP) and vicinity encompasses 1,905 square kilometers at the south end of the Cascade Range in Shasta, Lassen, Tehama, and Plumas Counties, northeastern California. Most of the map area is underlain by middle to late Pleistocene volcanic rocks; Holocene, early Pleistocene, and late Pliocene volcanic rocks (less than 3.5 m.y.) are less common. The southernmost Cascade Range consists of a regional platform of basalt and basaltic andesite, with subordinate andesite and sparse dacite, erupted from small, relatively short-lived volcanoes. Nested within these regional volcanoes are "volcanic centers," defined as large, long-lived, composite, calc-alkaline edifices erupting the full range of compositions from basalt to rhyolite, but dominated by andesite and dacite. Volcanic centers are produced by the focusing of basaltic flux from the ...
This preliminary geologic map presents mapping of the Leuhman Ridge area of Edwards Air Force Base, California, conducted between April 2020 and June 2021. The report focuses on surficial materials and bedrock to evaluate potential faults and other geologic features that may influence groundwater movement. The preliminary work confirms that the Spring Fault, previously mapped by Dibblee (1960, 1967), is a Quaternary-active fault but does not find convincing evidence to support the existence of the Leuhman Fault (Dibblee, 1960; 1967) within the map area. Several more possible and probable faults are identified by a combination of geomorphic lineaments and brecciated rock. Pleistocene and Holocene eolian deposits are widespread, manifesting as sand sheets, dunes, and admixtures into alluvial fans. Also, an incised pediment forms much of the upland south of Leuhman Ridge. In general, field observations indicate that Quaternary alluvial and eolian deposits are thin; this suggests that secondary bedrock porosity and permeability, defined by degree of weathering and fracture density that includes fault-related fracturing, are more important factors in the location and flow patterns of groundwater.
The Digital Geologic Map of the Point Loma Quadrangle and area immediately west, California is composed of GIS data layers complete with ArcMap 9.3 layer (.LYR) files, two ancillary GIS tables, a Map PDF document with ancillary map text, figures and tables, a FGDC metadata record and a 9.3 ArcMap (.MXD) Document that displays the digital map in 9.3 ArcGIS. The data were completed as a component of the Geologic Resources Inventory (GRI) program, a National Park Service (NPS) Inventory and Monitoring (I&M) funded program that is administered by the NPS Geologic Resources Division (GRD). Source geologic maps and data used to complete this GRI digital dataset were provided by the following: California Division of Mines and Geology. Detailed information concerning the sources used and their contribution the GRI product are listed in the Source Citation sections(s) of this metadata record (polm_metadata.txt; available at http://nrdata.nps.gov/cabr/nrdata/geology/gis/polm_metadata.xml). All GIS and ancillary tables were produced as per the NPS GRI Geology-GIS Geodatabase Data Model v. 2.1. (available at: http://science.nature.nps.gov/im/inventory/geology/GeologyGISDataModel.cfm). The GIS data is available as a 9.3 personal geodatabase (polm_geology.mdb), and as shapefile (.SHP) and DBASEIV (.DBF) table files. The GIS data projection is NAD83, UTM Zone 11N. That data is within the area of interest of Cabrillo National Monument.
State Geologic Map CompilationThis web map portrays the U.S. Geological Survey's (USGS) State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States. The SGMC represents a seamless, spatial database of 48 State geologic maps. Per USGS, "A national digital geologic map database is essential in interpreting other datasets that support numerous types of national-scale studies and assessments, such as those that provide geochemistry, remote sensing, or geophysical data. The SGMC is a compilation of the individual USGS releases of the Preliminary Integrated Geologic Map Databases for the U.S."A full discussion of the procedures and methodology used to create this dataset is available in the accompanying report: Horton, J.D., San Juan, C.A., and Stoeser, D.B, 2017, The State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States (ver. 1.1, August 2017): U.S. Geological Survey Data Series 1052, 46p.State Geologic Map CollectionData currency and source: See individual layers listed below.For more information: The State Geologic Map Compilation (SGMC) Geodatabase of the Conterminous United States For feedback please contact: ArcGIScomNationalMaps@esri.comLayers:State Geologic Map Compilation – PointsState Geologic Map Compilation – StructureState Geologic Map Compilation – GeologyState Geologic Map Compilation - Vector TilesU.S. Geological SurveyPer USGS, "The USGS provides science about the natural hazards that threaten lives and livelihoods; the water, energy, minerals, and other natural resources we rely on; the health of our ecosystems and environment; and the impacts of climate and land-use change."
This Open-File report is a digital geologic map database. This digital map database is compiled from previously published sources combined with some new mapping and modifications in nomenclature. The geologic map database delineates map units that are identified by general age and lithology following the stratigraphic nomenclature of the U. S. Geological Survey. For detailed descriptions of the units, their stratigraphic relations, sources of geologic mapping, and data on exploratory wells consult Yerkes (1997), and Yerkes and Showalter (1990).
This Open-File report is a digital geologic map database. This digital map database is prepared from a previously published map by Brabb (1989). The geologic map database delineates map units that are identified by general age, lithology and clast size following the stratigraphic nomenclature of the U. S. Geological Survey.
This edition of the Geologic Map of California was prepared in recognition of the California Geological Survey's 150th Anniversary. It is an all-digital product built on the original compilation of C.W. Jennings published in 1977, with some additions and modifications. The Geologic Map of California presents an overview of the geology and structure of the state. It represents the geologic features that one would find on a visit to any locality in the state. The restraints of scale limit the detail that can be shown, but the most important geologic features are portrayed. The distribution of the major rock types and the major structural elements are shown with sufficient detail to be useful for many purposes. Please see the map pamphlet (included in this digital package as a PDF document) for further information.