Online Links:
| Value | Definition |
|---|---|
| contact, certain | Contact whose position is certain |
| contact, inferred, queried | Contact whose position is questionable |
| Value | Definition |
|---|---|
| fault, approx. located | Fault whose position is not precisely known |
| fault, certain | Observed fault |
| fault, concealed | Fault whose position is concealed and inferred |
| fault, concealed, queried | Fault whose position is concealed and questionable |
| fault, inferred | Fault whose position is inferred |
| fault, inferred, queried | Fault whose position is inferred and questionable |
| map boundary | Boundary of mapped area |
| thrust fault, approx. located | Thrust fault whose position is not precisely known |
| thrust fault, certain | Observed thrust fault |
| thrust fault, concealed | Thrust fault whose position is concealed and inferred |
| thrust fault, concealed, queried | Thrust fault whose position is concealed and questionable |
| thrust fault, inferred | Thrust fault whose position is inferred |
| thrust fault, inferred, queried_ | Thrust fault whose position is inferred and questionable |
| water boundary, certain | Boundary of a body of water |
| Value | Definition |
|---|---|
| H2O | Body of water |
| I | Assemblage I - Berkeley Hills |
| IIB | Assemblage II - Hercules Area |
| III | Assemblage III - Pinole Area |
| IV | Assemblage IV - Martinez Area |
| Assemblage V - Diablo Valley Area | |
| (blank) | unknown |
| Value | Definition |
|---|---|
| 'San Pablo\Bay' | Location of San Pablo Bay |
| I | Assemblage I - Berkeley Hills |
| II | Assemblage II - Hercules Area |
| III | Assemblage III - Pinole Area |
| IV | Assemblage IV - Martinez Area |
| V | Assemblage V - Diablo Valley Area |
| VI | Assemblage VI - Eastern Area |
| (blank) | unknown |
| Value | Definition |
|---|---|
| fault, approx. located | Fault whose position is not precisely known |
| fault, certain | Observed fault |
| fault, concealed | Concealed fault whose position is inferred |
| fault, concealed, queried | Fault whose position is concealed and questionable |
| fault, inferred | Fault |
| map boundary | Boundary of the mapped area |
| thrust fault, certain | Observed thrust fault |
| thrust fault, inferred | Thrust fault whose position is inferred |
| water boundary, certain | Boundary of a body of water |
| Value | Definition |
|---|---|
| map boundary | Boundary of mapped area |
| (blank) | unknown |
| Value | Definition |
|---|---|
| map boundary | Boundary of mapped area |
| (blank) | unknown |
| Value | Definition |
|---|---|
| contact, certain | Observed contact |
| map boundary | Boundary of mapped area |
| water boundary, certain | Boundary of a body of water |
| Value | Definition |
|---|---|
| (blank) | unknown |
| Range of values | |
|---|---|
| Minimum: | 1 |
| Maximum: | 14 |
| Units: | unknown |
| Resolution: | 1 |
| Value | Definition |
|---|---|
| f.a., anticline, approx. located | Anticlinal fold axis whose position is not precisely known |
| f.a., anticline, certain | Observed anticlinal fold axis |
| f.a., anticline, concealed | Concealed anticlinal fold axis whose position is inferred |
| f.a., anticline, inferred | Anticlinal fold axis whose position is inferred |
| f.a., overturned anticline, approx | Overturned antclinal fold axis whose position is not precisely known |
| f.a., overturned anticline, certain | Overturned anticlinal fold axis whose position is certain |
| f.a., overturned anticline, conceal | Overturned anticlinal fold axis whose position is concealed |
| f.a., overturned syncline, approx | Overturned synclinal fold axis whose position is not precisely known |
| f.a., overturned syncline, certain | Overturned synclinal fold axis whose position is certain |
| f.a., syncline, approx. located | Synclinal fold axis whose position is not precisely known |
| f.a., syncline, certain | Synclinal fold axis whose position is known |
| f.a., syncline, concealed | Synclinal fold axis whose position is concealed and inferred |
| f.a., syncline, inferred | Synclinal fold axis whose position is inferred |
| map boundary | Boundary of mapped area |
| Value | Definition |
|---|---|
| bedding | Bedding orientation |
| ot bedding | Overturned bedding orientation |
| vert bedding | Bedding whose dip is 90 degrees |
| Range of values | |
|---|---|
| Minimum: | 3 |
| Maximum: | 90 |
| Units: | degrees |
| Resolution: | 1 |
| Range of values | |
|---|---|
| Minimum: | 0 |
| Maximum: | 358 |
| Units: | degrees |
| Resolution: | 1 |
| Value | Definition |
|---|---|
| map boundary | Boundary of mapped area |
| (blank) | unknown |
| Value | Definition |
|---|---|
| Qu | Surficial deposits, undivided (Pleistocene and Holocene) |
| Qls | Landslide deposits (Pleistocene and Holocene) |
| Tb | Basaltic intrusive rocks (Pliocene) |
| Tsv | Silicic intrusive rocks (Miocene) |
| KJf | Franciscan Complex (Jurassic to Upper Cretaceous) |
| Tbp | Bald Peak Basalt (Miocene) |
| Tst | Siesta Formation (Miocene) |
| Tm | Moraga Formation (Miocene) |
| Tor | Orinda Formation (Miocene) |
| Tcc | Claremont Chert (Miocene) |
| Tgs | Unnamed sandstone and siltstone (Eocene, Oligocene, and Miocene) |
| Tsh | Greenish gray shale (Eocene) |
| Kph | Pinehurst Shale (Late Cretaceous) |
| Kr | Redwood Canyon Formation (Late Cretaceous) |
| Ksc | Shephard Creek Formation (Late Cretaceous) |
| Ko | Oakland Conglomerate (Late Cretaceous) |
| Kjm | Joaquin Miller Formation (Late Cretaceous) |
| JKk | Knoxville Formation (Late Jurassic to Early Cretaceous) |
| Jsv | Keratophyre - Coast Range Ophiolite (Jurassic) |
| sp | Serpentinite - Coast Range Ophiolite (Jurassic) |
| Qmz | Montezuma Formation (Pleistocene) |
| Tmlu | Upper member - Mullholland Formation of Ham (1952) (Pliocene) |
| Tmll | Lower member - Mullholland Formation of Ham (1952) (Pliocene) |
| Tus | Unnamed sedimentary and volcanic rocks (Miocene and Pliocene) |
| Tpt | Pinole Tuff (Miocene) |
| Tlt | Lafayette Tuff (Miocene) |
| Tn | Neroly Sandstone (Miocene) |
| Tc | Cierbo Sandstone (Miocene) |
| Tbr | Briones Formation (Miocene) |
| Tbg | G member of Wagner (1978) - Briones Formation (Miocene) |
| Tbf | F member of Wagner (1978) - Briones Formation (Miocene) |
| Tbe | E member of Wagner (1978) - Briones Formation (Miocene) |
| Tbd | D member of Wagner (1978) - Briones Formation (Miocene) |
| Tbu | Upper sandstone and shale member - Briones Formation (Miocene) |
| Tbh | Hercules Shale Member - Briones Formation (Miocene) |
| Tbl | Lower sandstone and siltstone member - Briones Formation (Miocene) |
| Tro | Rodeo Shale, Hambre Sandstone, Tice Shale, and Oursan Sandstone, undivided (Miocene) |
| Tr | Rodeo Shale (Miocene) |
| Th | Hambre Sandstone (Miocene) |
| Tt | Tice Shale (Miocene) |
| To | Oursan Sandstone (Miocene) |
| Tcs | Claremont Shale (Miocene) |
| Ts | Sobrante Sandstone (Miocene) |
| Tts | Tuffaceous sandstone (Oligocene or Miocene?) |
| Tsr | San Ramon Sandstone (Oligocene and/or Miocene) |
| Tshc | Shale and claystone (Eocene) |
| Tcgl | Conglomerate, sandstone, siltstone (Miocene and Pliocene) |
| Tut | Tuff (Miocene) |
| Tdi | Diatomite (Miocene) |
| Tsa | Sandstone (Miocene) |
| Tmu | Mudstone, shale, and siltstone (Miocene) |
| Tes | Escobar Sandstone of Weaver (1953) (Eocene) |
| Tehs | Sandstone and shale member - Escobar Sandstone of Weaver (1953) (Eocene) |
| Teh | Basal shale member - Escobar Sandstone of Weaver (1953) (Eocene) |
| Tmr | Muir Sandstone of Weaver (1953) (Eocene) |
| Tmru | Upper member - Muir Sandstone of Weaver (1953) (Eocene) |
| Tmrl | Lower member - Muir Sandstone of Weaver (1953) (Eocene) |
| Tlj | Las Juntas Shale of Weaver (1953) (Paleocene and Eocene) |
| Tlju | Upper member - Las Juntas Shale of Weaver (1953) (Paleocene and Eocene) |
| Tljl | Lower member - Las Juntas Shale of Weaver (1953) (Paleocene and Eocene) |
| Tvh | Vine Hill Sandstone of Weaver (1953) (Paleocene) |
| Tvhu | Upper member - Vine Hill Sandstone of Weaver (1953) (Paleocene) |
| Tvhl | Lower member - Vine Hill Sandstone of Weaver (1953) (Paleocene) |
| Ku | Great Valley sequence (Cretaceous) |
| Kcs | Gray, massive quartz arenite - Great Valley sequence (Cretaceous) |
| Ksh | Siltstone and shale - Great Valley sequence (Cretaceous) |
| Kus | Sandstone, siltstone, and shale |
| Kuh | Massive sandstone, minor siltstone |
| Tgvt | Green Valley and Tassajara Formations of Conduit (1938), undivided (Miocene and Pliocene) |
| Tdu | Upper member - Domingene Formation (Eocene) |
| Tdl | Lower member - Domingene Formation (Eocene) |
| Tdls | Sandstone - Domingene Formation (Eocene) |
| Kslt | Siltstone with minor shale, claystone, and sandstone. (Late Cretaceous) |
| Ttu | Tulare Formation (Pliocene) |
| Tl | Lawlor Tuff (Pliocene) |
| Tkt | Kirker Tuff (Oligocene) |
| Tmk | Markley Formation (Eocene) |
| Tmku | Upper member - Markley Formation (Eocene) |
| Tmkl | Lower member - Markley Formation (Eocene) |
| Tlu | Upper siltstone bed - Lower member - Markley Formation (Eocene) |
| Tll | Lower siltstone bed - Lower member - Markley Formation (Eocene) |
| Tsu | Upper part - Sidney Flat Shale Member - Markley Formation (Eocene) |
| Tsl | Lower part - Sidney Flat Shale Member - Markley Formation (Eocene) |
| Tnv | Nortonville Shale (Eocene) |
| Td | Domingene Formation (Eocene) |
| Tm | Meganos Formation (Paleocene) |
| Tme | Upper member - Meganos Formation (Paleocene) |
| Tmd | Sandstone member - Meganos Formation (Paleocene) |
| Tmc | Shale member - Meganos Formation (Paleocene) |
| Tmcss | Sandstone interbeds - Meganos Formation (Paleocene) |
| Tma | Lower member - Meganos Formation (Paleocene) |
| Tmz | Unnamed sandstone and shale (Paleocene) |
| Tmzu | Upper member - Unnamed sandstone and shale (Paleocene) |
| Tmzl | Lower member - Unnamed sandstone and shale (Paleocene) |
| Kdv | Deer Valley Sandstone of Colburn (1964) (Late Cretaceous) |
| Keu | Upper member - Unit E - Great Valley sequence (Jurassic and Cretaceous) |
| Kel | Lower member - Unit E - Great Valley sequence (Jurassic and Cretaceous) |
| Kels | Sandstone interbeds - Unit E - Great Valley sequence (Jurassic and Cretaceous) |
| Kd | Unit D - Sandstone (Late Cretaceous) - Great Valley sequence (Jurassic and Cretaceous) |
| Kds | Shale member - Unit D - Great Valley sequence (Jurassic and Cretaceous) |
| Kcu | Upper member - Unit C - Sandstone and shale (Late Cretaceous) - Great Valley sequence (Jurassic and Cretaceous) |
| Kcus | Upper member sandstone - Upper member - Unit C - Great Valley sequence (Jurassic and Cretaceous) |
| Kcm | Middle member - Unit C - Great Valley sequence (Jurassic and Cretaceous) |
| Kcl | Lower member - Unit C - Great Valley sequence (Jurassic and Cretaceous) |
| Kcls | Lower member sandstone - Unit C - Great Valley sequence (Jurassic and Cretaceous) |
| Kb | Unit B - Sandstone and shale (Early Cretaceous) - Great Valley sequence (Jurassic and Cretaceous) |
| Kbsh | Shale member - Unit B - Great Valley sequence (Jurassic and Cretaceous) |
| Kbs | Sandstone member - Unit B - Great Valley sequence (Jurassic and Cretaceous) |
| Ka | Unit A - Shale, with minor sandstone (Early Cretaceous) - Great Valley sequence (Jurassic and Cretaceous) |
| Kas | Sandstone member - Unit A - Great Valley sequence (Jurassic and Cretaceous) |
| JKk | Knoxville Formation (Late Jurassic to Early Cretaceous) |
| Jpb | Pillow basalt, basalt breccia, and minor diabase - Coast Range Ophiolite (Jurassic) |
| Jdb | Diabase - Coast Range Ophiolite (Jurassic) |
| sc | Silica carbonate rocks - Coast Range Ophiolite (Jurassic) |
| H20 | Body of water |
| Value | Definition |
|---|---|
| contact, approx. located | Contact whose position is not precisely known |
| contact, certain | Observed contact |
| contact, concealed | Concealed contact whose position is inferred |
| contact, inferred | Contact whose position is inferred |
| contact, inferred, queried | Contact whose position is inferred and questionable |
| fault, approx. located | Fault whose position is not precisely known |
| fault, certain | Observed fault |
| fault, concealed | Concealed fault whose position is inferred |
| fault, concealed, queried | Concealed fault whose position is questionable |
| fault, inferred | Fault whose position is inferred |
| fault, inferred, queried | Fault whose position is inferred and questionable |
| map boundary | Boundary of mapped area |
| scratch boundary | Location of scratch boundary |
| thrust fault, approx. located | Thrust fault whose position is not precisely known |
| thrust fault, certain | Observed thrust fault |
| thrust fault, concealed | Concealed thrust fault whose position is inferred |
| thrust fault, inferred | Thrust fault whose position is inferred |
| thrust fault, inferred, queried_ | Thrust fault whose position is inferred and questionable |
| water boundary, certain | Boundary of a body of water |
| (blank) | unknown |
J. Ross Wagner, Montgomery Watson Consultants, Walnut Creek, kindly shared his extensive and high quality unpublished geologic maps covering the area from Pinole to San Ramon (see ccsource.txt). Thomas D. Barrow, President of Exxon, graciously released unpublished geologic mapping and paleontologic information collected by Howard S. Sonneman and John R. Switzer, Jr. covering most of the central and all of the eastern part of the county. We are grateful to James R. LeCompte who compiled these maps and other data in the 1970's. This drafted copy was scanned and initially edited and tagged by Maureen A. Kelly in consultation with Carl M. Wentworth. We are also grateful to Kristin R. McDougall, William V. Sliter, David Bukry, John A. Barron, and William P. Elder for paleontologic determinations, Marvin A Lanphere and Robert J. Fleck for the determination of the age of volcanic rocks, and Andrei M. Sarna-Wojcicki for correlation of volcanic tuffs that helped establish the stratigraphic sequence and structural complexity of the geologic units. Alvin A. Almgren, Unocal (retired) reviewed early versions of this map and provided much new information. Philip J. Stuecheli, Geotechnical Engineering Consultants, provided access and subdivision maps for an area under construction in Clayton. Tim D. Bray, consultant and Prof. Raymond Sullivan, San Francisco State Univ., arranged for access to cores and other geologic information in the Keller Canyon landfill area south of Pittsburg. David J. Gross, Woodward-Clyde Consultants, provided geologic maps and arranged for access to cores in the Los Vaqueros Dam area near Byron. Laurel Collins helped provide access to lands owned by the East Bay Regional Park District. Larry J. Dickerson and John M. Parker provided extensive support in the field. Carl Wentworth and Geoff Phelps provided assistance with Alacarte and ARC/INFO.
The purpose of this report is to provide to the public a digital geologic map database, and together with the accompanying text file (ccgeo.txt), it provides current information on the stratigraphy and structural geology of the area covered.
Are there legal restrictions on access or use of the data?Access_Constraints: None
Use_Constraints: None
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 emphasizing bedrock formations in Contra Costa County, California: 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.
| Data format: |
ARC/INFO Coverages Description of coverage cc_utm Faults, depositional contacts, and rock unit identities cc_sr Fold axes, strike and dip information cc-flt_utm cc-flt_ano Together, these ARC coverages contain a fault map of Contra Costa County with major faults labeled cc_dr Drainage base map cc_cu Cultural base map cc_topo Topographic contours base map cc_so Index map of sources of data cc_as Index map of Assemblages in Contra Costa County cc_quad cc-quad_ano Together, these ARC coverages contain an index map of 7.5 minute quadrangles in Contra Costa County cc-corr_utm Correlation table for the units in these mapsin format ARCE (version 6.x) Size: 21.2 |
|---|---|
| Network links: |
http://pubs.usgs.gov/of/1994/of94-622/cc_g1.tar.Z |