USGS Geoscience Data Catalog
Additional USGS Geoscience data can be found by geographic location or by publication series.
Yerkes, R. F., and Campbell, R. H., 1995, Preliminary geologic map of the Topanga 7.5' quadrangle, southern California: A digital database: U.S. Geological Survey Open-File Report 95-91.
This is a vector data set. It contains the following vector data types (SDTS terminology):
Planar coordinates are encoded using coordinate pair
Abscissae (x-coordinates) are specified to the nearest unknown
Ordinates (y-coordinates) are specified to the nearest unknown
Planar coordinates are specified in meters
|contact, approx. located||Contact whose position is not precisely located|
|contact, certain||Observed geologic contact|
|contact, inferred||Contact whose position is inferred|
|detachment fault, approx. located||Detachment fault whose position is not precisely known|
|dike, approx. located||Dike whose position is not precisely known|
|dike, diabase||Location of a diabase dike|
|fault, approx. located||Fault whose position is not precisely known|
|fault, concealed||Concealed fault whose position is inferred|
|map boundary, certain||Boundary of mapped area|
|named fault||Fault with a proper name|
|thrust fault, approx. located||Thrust fault whose position is not precisely known|
|f.a., anticline, approx. located||Anticlinal fold axis whose position is not precisely known|
|f.a., anticline, concealed||Anticlinal fold axis whose position is concealed and inferred|
|f.a., syncline, approx. located||Synclinal fold axis whose position is not precisely known|
|f.a., syncline, certain||Observed synclinal fold axis|
|f.a., syncline, concealed||Concealed synclinal fold axis whose position is inferred|
|air photo attitude||Attitude of bedding as determined from air photos|
|approx bedding||Bedding whose orientation is not precisely known|
|ot bedding||Overturned bedding|
|vert bedding||Bedding with a dip of 90 degrees|
|Range of values|
|Range of values|
R. H. Campbell, Reston, VA assisted in field interpretations and compilation; P. K. Showalter and C. M. Wentworth supplied critical custom programming; and S. E. Graham updated supporting files for completeness and consistency and prepared this report.
To provide to the public a digital geologic map database of the Topanga 7.5' quadrangle, southern California.
Yerkes, R.F., and Campbell, R.H., 1994, Preliminary geologic map of the Topanga 7.5' quadrangle, southern California: U.S. Geological Survey Open-File Report 94-266.
Yerkes, R.F., and Showalter, P.K., 1990, Exploratory wells drilled in the Los Angeles, California 1:100,000 quadrangle, southern California: U.S. Geological Survey Open-File Report 90-627.
Person who carried out this activity:
This database is not sufficiently detailed or comprehensive to identify or characterize site- specific hazards represented by faults or landslides shown; the faults shown do not take the place of fault-rupture hazard zones designated by the California State Geologist (see Hart, 1988).
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 and sources of geologic mapping consult Yerkes and Campbell (1994).
Are there legal restrictions on access or use of the data?
- Access_Constraints: None
- Use_Constraints: None
US Geological Survey Open-File Report 95-91
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 "Preliminary Geologic Map of the Topanga 7.5' Quadrangle, southern California: A Digital Database," has been approved for release and publication by the Director of the USGS. Although this database has been reviewed and is substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review. This database is released on condition that neither the USGS nor the U. S. Government may be held liable for any damages resulting from its use.
ARC/INFO export files Description of coverage tp-geol.e00 Depositional contacts, faults, and unit labels tp-strc.e00 Strike and dip information, fold axes tp-foss.e00 Fossil localities tp-topo.e00 Topographic base map taken from a scan of a composite negative of the Topanga 7.5 minute quadrangle (contour interval = 25 ft.)in format ArcInfo export (version 7.x) Size: 21 megabytes
A compressed tar file of the geologic map database and related files can be obtained by sending a tape with request and return address to:
Topanga, CA 7.5' Geologic Database c/o Database Coordinator US Geological Survey 345 Middlefield Road, M/S 975 Menlo Park, CA 94025Do not omit any part of this address!
The compressed tar file will be returned on the tape. The acceptable tape types are: 1/4 inch, 150 MB cartridge tape, 2.3 or 5.0 GB, 8 mm Exabyte tape.