USGS Geoscience Data Catalog
Additional USGS Geoscience data can be found by geographic location or by publication series.
Database includes: ARC/INFO export file Description of coverage cd_sp-py.e00 Faults, depositional contacts, and rock units in the Cordelia 7.5 minute quadrangle cd_sp-sr.e00 Strike and dip information and fold axes in the Cordelia 7.5 minute quadrangle be_sp-py.e00 Faults, depositional contacts, and rock units in the northern part of the Benicia 7.5 minute quadrangle be_sp-sr.e00 Strike and dip information and fold axes in the northern part of the Benicia 7.5 minute quadrangle cd_sp-flt.e00 Index map of faults in the Cordelia 7.5 minute quadrangle with annotation showing the names of major faults be_sp-flt.e00 Index map of faults in the northern part of the Benicia 7.5 minute quadrangle with annotation showing the names of major faults cdbe_corr.e00 Correlation table for the units in this map database. This database is not geospatial cdbe_so.e00 Sources of data index map for this map database. Arcs only. cdbe_as.e00 Index map of Assemblages in the Cordelia and the northern part of the Benicia 7.5 minute quadrangles. cdxs_sp-ln.e00 Map showing location of cross-sections. Arcs only. cdxsa.e00 Cross-section A. This database is not geospatial. cdxsb.e00 Cross-section B. This database is not geospatial. Other files Description cdbegeo.ps A PostScript plot file of a report containing detailed unit descriptions and geological information, plus sources of data and references cited. cdbegeo.pdf A PDF version of cdbegeo.ps cdbegeo.txt A text-only file containing an unformatted version of cdbegeo.ps cdbedb.ps A PostScript plot file containing information on the database files. cdbedb.pdf A PDF version of cdbedb.ps. cdbedb.txt A text-only file containing an unformatted version of cdbedb.ps import.aml ASCII text file in ARC Macro Language to convert ARC export files to ARC coverages in ARC/INFO. cdbekey.txt Together, these three ASCII text files contain the information given in the description of map units and symbols on the map sheet (cdbemap.ps or cdbemap.pdf) cdbekey2.txt cdbekeysym.txt cdbeso.txt ASCII text file containig information about sources of data as shown in the sources of data index map (cdbe_so) described above.
Graymer, R.W., Brabb, E.E., and Jones, D.L., 1999, Geology of the Cordelia and the northern part of the Benicia 7.5 minute quadrangles, California: A digital map database: U.S. Geological Survey Open-File Report 99-162.Online Links:
This is a Vector data set. It contains the following vector data types (SDTS terminology):
Planar coordinates are encoded using coordinate pair
Planar coordinates are specified in meters
| Value | Definition |
|---|---|
| af | Artificial fill (Historic) |
| alf | Artificial levee fill (Historic) |
| Qhasc | Artificial stream channels (Historic) |
| Qhsc | Stream channel deposits (Holocene) |
| Qhbm | Bay mud (Holocene) |
| Qhaf | Alluvial fan and fluvial deposits (Holocene) |
| Qcl | Colluvium (Holocene) |
| Qls | Landslide deposits (Pleistocene and/or Holocene) |
| Qpaf | Alluvial fan and fluvial deposits (Pleistocene) |
| Qpoaf | Older alluvial fan deposits (Pleistocene) |
| Tsv | Sonoma Volcanics, undivided (Pliocene and Miocene?) |
| Tss | Volcanic mudstone, sandstone, and conglomerate: Sonoma Volcanics, undivided (Pliocene and Miocene?) |
| Tc | Cierbo Sandstone (Miocene) |
| Tv | Unnamed volcanics (Miocene?) |
| Tmk | Markley Formation (Eocene) |
| Tmkj | Jameson Mudstone member: Markley Formation (Eocene) |
| Tnv | Nortonville Shale (Eocene) |
| Td | Domingene Sandstone (Eocene) |
| Tmr | Muir Sandstone of Weaver (1953) (Eocene) |
| Tlj | Las Juntas Shale of Weaver (1953) (Paleocene and Eocene) |
| Tvh | Vine Hill Sandstone of Weaver (1953) (Paleocene) |
| Ku | Undivided sandstone and shale (Early and Late Cretaceous) |
| KJk | Knoxville Formation (Late Jurassic and Early Cretaceous) |
| Jsv | Silicic volcanic rocks (Late Jurassic) |
| Jb | Basalt: Coast Range Ophiolite (Jurassic) |
| Jgb | Gabbro: Coast Range Ophiolite (Jurassic) |
| sp | Serpentinite: Coast Range Ophiolite (Jurassic) |
| KJfm | Franciscan melange: Franciscan Complex (Cretaceous and Jurassic) |
| ls | Algal limestone (age unknown) |
| H2O | water |
| Value | Definition |
|---|---|
| fault, approx. located | Fault whose position is not precisely known. |
| fault, certain | Fault whose position is certain. |
| fault, concealed | Fault that is concealed and its position inferred. |
| reverse fault, approx. located | Reverse fault whose positions is not presicesly known. |
| reverse fault, certain | Reverse fault whose position was observed. |
| reverse fault, concealed | Reverse fault that is concealed and its position inferred. |
| thrust fault, approx. located | Thrust fault whose position is not precisely known. |
| thrust fault, certain | Thrust fault that was observed. |
| thrust fault, inferred | Thrust fault whose position is inferred. |
| Value | Definition |
|---|---|
| contact, approx. located | Contact whose position is not precisely known. |
| contact, certain | Contact that was observed. |
| contact, inferred | Contact whose position is inferred. |
| fault, approx. located | Fault whose position is not precisely known. |
| fault, certain | Observed fault. |
| fault, concealed | Fault that is concealed and its position inferred. |
| map boundary | Boundary of mapped quadrangle |
| reverse fault, approx. located | Reverse fault whose position is not precisely known. |
| reverse fault, certain | Observed reverse fault |
| reverse fault, concealed | Reverse fault whose position is concealed and inferred. |
| thrust fault, approx. located | Thrust fault whose position is not precisely known. |
| thrust fault, certain | Observed thrust fault. |
| thrust fault, inferred | Thrust fault whose position is inferred. |
| water boundary | Boundary of a body of water. |
| Value | Definition |
|---|---|
| f.a., anticline, approx. located | Anticline whose position is not precise. |
| f.a. anticline, certain | Observed anticline |
| f.a., anticline, concealed | Anticline that is concealed and position inferred. |
| f.a., syncline, approx. located | Syncline whose position is not precise. |
| f.a. syncline, certain | Observed syncline |
| f.a., syncline, concealed | Syncline that is concealed and its position inferred. |
We are grateful to the following U.S. Geological Survey paleontologists who have examined our fossils and provided ages necessary to establish the stratigraphic sequence and structure: David Bukry (Cretaceous and Tertiary nannoplankton), Kristin McDougall (Tertiary foraminifers), William Sliter (deceased - Cretaceous and Eocene foraminifers), John Barron (Tertiary diatoms), Charles Powell II (Tertiary mollusks), and Bonita Murchey (Mesozoic radiolaria).
We are also very grateful to managers and staff of Chevron, EXXON, UNOCAL, ARCO, and Shell Petroleum Companies who have provided reports, maps, picked slides, and residues for about 25,000 microfossil localities in the San Francisco Bay Region.
Carl Wentworth kindly provided advice on digitizing and editing procedures. Ed Helley provided materials and advice on Quaternary units.
To provide current information on the geologic structure and stratigraphy of a geologic map of the Cordelia and the northern part of the Benicia 7.5' quadrangles, California.
Graymer, R.W., Jones, D.L., and Brabb, E.E., 1994, Preliminary geologic map emphasizing bedrock formations in Contra Costa County, California: A digital database: U.S. Geological Survey Open-File Report OFR-94-622.
Complete
This map database represents the integration of previously published and unpublished maps by several workers and new geologic mapping and field checking by the authors.
Are there legal restrictions on access or use of the data?
- Access_Constraints: none
- Use_Constraints: none
USGS Open-File report 99-162
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 "Geology of the Cordelia and the northern part of the Benicia 7.5 minute quadrangles, California: A digital map 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.
| Data format: | Geologic units and structural features in format ArcInfo export (version 7.0.4) Size: 0.9 megabytes |
|---|---|
| Network links: |
<http://pubs.usgs.gov/of/1999/of99-162/o99-162c.tgz> |
Database files, PostScript plotfiles, and related files can be obtained by sending a tape with request and return address to:
Cordelia and the northern part of the Benicia 7.5 minute quadrangles Geologic Database c/o Database Coordinator U.S. Geological Survey 345 Middlefield Road, M/S 975 Menlo Park, CA 94025Do not omit any part of this address!
NOTE: Be sure to include with your request the exact names, as listed above, of the tar files you require. An Open-File Report number is not sufficient, unless you are requesting both the database package and plotfile package for the report.
The compressed tar file will be returned on the tape. The acceptable tape types are: 2.3 or 5.0 GB, 8 mm Exabyte tape.
703-648-6974 (voice)
703-648-6560 (FAX)
pschweitzer@usgs.gov