Brabb, E.E. Graymer, R.W. Jones, D.L. 1998 map U.S. Geological Survey Open-File Report 98-137 Menlo Park, CA U.S. Geological Survey http://pubs.usgs.gov/of/1998/of98-137/ This digital map database, compiled from previously published and unpublished data, and new mapping by the authors, represents the general distribution of bedrock and surficial deposits in San Mateo County. Together with the accompanying text, it provides current information on the geologic stucture and stratigraphy of the area covered. The database delineates map units that are identified by general age and lithology following the stratigraphic nomenclature of the U.S. Geological Survey. The scale of the source maps limits the spatial resolution (scale) of the database to 1:62,500 or smaller. This map is intended to be of general use to engineers and land-use planners. However, its small scale does not provide sufficient detail for site development purposes. In addition, this map does not take the place of fault-rupture hazard zones designated by the California State Geologist (Hart, 1988). Similarly, the database cannot be used to identify or delineate landslides in the region. For a depiction of landslide distribution, see Brabb and Pampeyan (1972), Brabb and others (1978), Mark (1992), Wieczorek and others (1985), and Wieczorek and others (1988). Additional information is available in two textual reports: smgeo.ps is a PostScript report containing detailed unit descriptions and geological information, sources of data and cited references. The text is available in smgeo.txt. smdb.ps is a PostScript report describing the structure of the database. The text is available in smdb.txt. >ARC/INFO coverages >sm_um-py.e00 > Faults, depositional contacts, and rock units in San Mateo County >sm_um-sr.e00 > Strike and dip information and fold axes in San Mateo County >sm_quad.e00 > Index map of quadrangles in San Mateo County. >sm_um-flt.e00 > Index map of faults in San Mateo County with annotation showing the names of major faults. >sm_corr.e00 > Correlation table for the units in this map database. >sm_so.e00 > Sources of data index map for this map database. >sm_as.e00 > Index map of Assemblages in San Mateo County. (Assemblages are described in smgeo.txt or smgeo.ps) >sm_um-dr.e00 > Drainage base map (from 1:100,000 scale original). >sm_um-cu.e00 > Cultural base map (from 1:100,000 scale original). >sm_um-topo.e00 > Topographic contours base map (from 1:100,000 scale original). ARC/INFO coverage sm_um-py.e00 Faults, depositional contacts, and rock units in San Mateo County ARC/INFO coverage sm_um-sr.e00 Strike and dip information and fold axes in San Mateo County ARC/INFO coverage sm_quad.e00 Index map of quadrangles in San Mateo County. ARC/INFO coverage sm_um-flt.e00 Index map of faults in San Mateo County with annotation showing the names of major faults. ARC/INFO coverage sm_corr.e00 Correlation table for the units in this map database. ARC/INFO coverage sm_so.e00 Sources of data index map for this map database. ARC/INFO coverage sm_as.e00 Index map of Assemblages in San Mateo County. (Assemblages are described in smgeo.txt or smgeo.ps) ARC/INFO coverage sm_um-dr.e00 Drainage base map (from 1:100,000 scale original). ARC/INFO coverage sm_um-cu.e00 Cultural base map (from 1:100,000 scale original). ARC/INFO coverage sm_um-topo.e00 Topographic contours base map (from 1:100,000 scale original). 1998 Date given is publication date. Age of the rocks described in this map ranges from Jurassic through Holocene, with some occurrence of metamorphic rocks thought to be Paleozoic. Complete Irregular. The USGS Open-File Reports are used for rapid release of information to the public; this map will likely be superseded by one in the more formal Miscellaneous Investigations map series in the next few years. -122.554 -122.075 37.717 37.100 none Bedrock geology Surficial geology Sedimentary depositional environments Faults Depositional contacts Rock units fold axes GNIS San Mateo County, CA California None Anchor Bay Conglomerate Butano Sandstone Colma Formation Franciscan Complex Ladera Sandstone Lambert Shale Lobitos Mudstone Member Lompico Sandstone Merced Formation Mindego Basalt Monterey Formation Page Mill Basalt Pigeon Point Formation Pomponio Mudstone Member Purisima Formation Rices Mudstone Member San Gregorio Sandstone Member San Lorenzo Formation Santa Clara Formation Santa Cruz Mudstone Santa Margarita Sandstone Tahana Member Tunitas Sandstone Member Twobar Shale Member Vaqueros Sandstone Whiskey Hill Formation None Jurassic Cretaceous Tertiary Paleocene Eocene Oligocene Miocene Pliocene Quaternary Holocene National Geologic Map Database Catalog themes, augmented 2100 - Transportation 2101 - Roads 2102 - Railroads 2500 - Political Boundaries 2502 - County Boundaries 2503 - City Boundaries or Locations 2200 - Hydrography 2201 - Streams 2202 - Lakes 2203 - Coastline 2600 - Topography 2601 - Contours 1100 - Geology 1101 - General ISO 19115 Topic Categories geoscientificInformation Augmented FIPS 10-4 and FIPS 6-4, version 1.0 06081 = San Mateo None None USGS Western Geologic Mapping Team Russ Graymer mailing and physical address

345 Middlefield Road, MS 975

Menlo Park CA 94025 USA 650-329-4921 rgraymer@usgs.gov http://pubs.usgs.gov/of/1998/of98-137/smmap.jpg Image of entire map on black background JPEG http://pubs.usgs.gov/of/1998/of98-137/smmap.pdf A PDF representation of the Quaternary geologic map and base maps of San Mateo County and surrounding areas at a scale of 1:62,500 (Sheet 1). 5.5 megabytes. PDF http://pubs.usgs.gov/of/1998/of98-137/smexpl.pdf A PDF representation of the map keys and index maps for San Mateo County (Sheet 2). 1.2 megabytes. PDF 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), Willam 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. We are grateful to Tracey Felger, who made the original scan and a preliminary edit of author materials; to Judy Mariant, who did additional editing and tagging of lines; and to Dominique Garnier, who digitized many of the bedding attitudes. Carl Wentworth kindly provided advice on digitizing and editing procedures. Ed Helley provided materials and advice on Quaternary units. The databases in this repot were compiled in ARC/INFO, a commercial Geographic Information System (Environmental Systems Research Institute, Redlands, California), with version 3.0 of the menu interface ALACARTE (Fitzgibbon and Wentworth, 1991, Fitzgibbon, 1991, Wentworth and Fitzgibbon, 1991). The files are in either GRID (ARC/INFO raster data) format or COVERAGE (ARC/INFO vector data) format. Coverages are stored in uncompressed ARC export format (ARC/INFO version 7.x). ARC/INFO export files (files with the .e00 extension) can be converted into ARC/INFO coverages in ARC/INFO (see below) and can be read by some other Geographic Information Systems, such as MapInfo via ArcLink and ESRI's ArcView (version 1.0 for Windows 3.1 to 3.11 is available for free from ESRI's web site: http://www.esri.com/ ). The digital compilation was done in version 7.0.4 of ARC/INFO with version 3.0 of the menu interface ALACARTE (Fitzgibbon and Wentworth, 1991, Fitzgibbon, 1991, Wentworth and Fitzgibbon, 1991). The PostScript plotfiles for maps were produced by the "postscript" command with compression set to zero in ARC/INFO version 7.0.4. The PostScript plotfiles for pamphlets were produced in Microsoft Word 6.0 using the Destination PostScript File option from the Print command. The map is compiled from 20 different sources, including direct observations by the authors. One of the included coverages (SM_SO.E00) indicates the geographic area covered by each of the source maps. Citations for published sources are given in the lineage, and unpublished sources and original mapping are described in the appropriate process step. The mapped area includes parts of the Pacific Ocean, San Francisco Bay, and several large lakes; these areas are identified as water bodies and the geologic units underlying them are not indicated in this report. Uses of this digital geologic map should not violate the spatial resolution of the data. Although the digital form of the data removes the constraint imposed by the scale of a paper map, the detail and accuracy inherent in map scale are also present in the digital data. The fact that this database was edited at a scale of 1:24,000 means that higher resolution information is not present in the dataset. Plotting at scales larger than 1:24,000 will not yield greater real detail, although it may reveal fine-scale irregularities below the intended resolution of the database. Similarly, where this database is used in combination with other data of higher resolution, the resolution of the combined output will be limited by the lower resolution of these data. Note that in contrast to the geologic coverages, the base map layers have a resolution of 1:100,000, so significant discrepancies with the geologic coverages are possible. The base map layers are provided for reference only. U.S. Geological Survey 1982 map 100000 scale-stable printing negatives 1982 edition date Palo Alto base map Base map layer used to compile this geologic map. U.S. Geological Survey 1978 map 100000 scale-stable printing negatives 1978 edition date San Francisco base map Base map layer used to compile this geologic map. Brabb, E.E. Graymer, R.W. Jones, D.L. 1998 map U.S. Geological Survey Open-File Report 98-137 Menlo Park, CA U.S. Geological Survey http://pubs.usgs.gov/of/1998/of98-137/sm_g1.tar.gz 100000 digital 1998 edition date sm_um-dr Drainage base map (from 1:100,000 scale original) produced in compiling this map, supplied for reference only. Brabb, E.E. Graymer, R.W. Jones, D.L. 1998 map U.S. Geological Survey Open-File Report 98-137 Menlo Park, CA U.S. Geological Survey http://pubs.usgs.gov/of/1998/of98-137/sm_g1.tar.gz 100000 digital 1998 edition date sm_um-cu Cultural base map (from 1:100,000 scale original) produced in compiling this map, supplied for reference only. Brabb, E.E. Graymer, R.W. Jones, D.L. 1998 map U.S. Geological Survey Open-File Report 98-137 Menlo Park, CA U.S. Geological Survey http://pubs.usgs.gov/of/1998/of98-137/sm_g1.tar.gz 100000 digital 1998 edition date sm_um-topo Topographic contours base map (from 1:100,000 scale original) produced in compiling this map, supplied for reference only. Bonilla, M.G. 1965 U.S. Geological Survey Open-File Report 65 20000 paper 1965 publication date Bonilla (1965) Source map for region 1 (see coverage sm_so) Brabb, E.E. 1960 Stanford, California Stanford University Ph.D. thesis 24000 paper 1960 publication date Brabb (1960) Source map for region 18 (see coverage sm_so) Brabb, E.E. 1964 American Association of Petroleum Geologists Bulletin v. 48, no. 5 p. 670-697 24000 paper 1964 publication date Brabb (1964) Source map for region 18 (see coverage sm_so) Brabb, E.E. Clark, J.C. Throckmorton, C.K. 1977 U.S. Geological Survey Open-File Report 77-714 paper 1977 publication date Brabb and others (1977) Source map for region 20 (see coverage sm_so) Brown, R.D., Jr. 1972 U.S. Geological Survey Miscellaneous Field Studies Map MF-355 62500 paper 1972 publication date Brown (1972) Source map for region 10 (see coverage sm_so) Clark, J.C. 1970 U.S. Geological Survey Open-File Report 70 24000 paper 1970 publication date Clark (1970) Source map for region 20 (see coverage sm_so) Clark, J.C. 1981 U.S. Geological Survey Professional Paper 1168 24000 paper 1981 publication date Clark (1981) Source map for region 20 (see coverage sm_so) Clark, J.C. Brabb, E.E. 1978 California Division of Mines and Geology Special Report 137 paper 1978 publication date Clark and Brabb (1978) Source map for region 20 (see coverage sm_so) Classen, J.S. 1959 Stanford, California Stanford University M.S. thesis 21000 paper 1959 publication date Classen (1959) Source map for region 7 (see coverage sm_so) Cummings, J.C. 1960 Stanford, California Stanford University Ph.D. thesis 24000 paper 1960 publication date Cummings (1960) Source map for regions 16 and 19 (see coverage sm_so) Cummings, J.C. Touring, R.M. Brabb, E.E. 1962 California Division of Mines and Geology Bulletin 181 p. 179-220 48000 paper 1962 publication date Cummings and others (1962) Source map for regions 14, 16, 18, and 19 (see coverage sm_so) Darrow, R.L. 1963 California Division of Mines and Geology Special Report 78 35000 paper 1963 publication date Darrow (1963) Source map for region 2 (see coverage sm_so) Dibblee, T.W., Jr. 1966 California Division of Mines and Geology Map 8 62500 paper 1966 publication date Dibblee (1966) Source map for regions 12, 15, and 16 (see coverage sm_so) Esser, R.W. 1958 Stanford, California Stanford University M.S. thesis 24000 paper 1958 publication date Esser (1958) Source map for region 11 (see coverage sm_so) Glen, William 1959 California University Publications, Geological Science v. 36, no. 2 p. 147-197 44000 paper 1959 publication date Glen (1959) Source map for region 4 (see coverage sm_so) Hall, C.A., Jr. Jones, D.L. Brooks, S.A. 1959 American Association of Petroleum Geologists Bulletin v. 43, no. 12 p. 2855-2859 175000 paper 1959 publication date Hall and others (1959) Source map for region 17 (see coverage sm_so) Hall, N.T. 1965 California California University M.A. thesis paper 1965 publication date Hall (1965a) Source map for region 1 (see coverage sm_so) Hall, N.T. 1965 p. 151-158 Northern Great Basin and California-International Association of Quaternary Research 1965 Lincoln, Nebraska Nebraska Academy of Science paper 1965 publication_date Hall (1965b) Source map for region 1 (see coverage sm_so) Helley, E.J. Graymer, R.W. 1997 U.S. Geological Survey Open-File Report 97-97 digital 1997 publication date Helley and Graymer (1997) Source map for region 13 (see coverage sm_so) Jack, R.N. 1969 Berkeley, California California University M.A. thesis 10000 paper 1969 publication date Jack (1969) Source map for region 4 (see coverage sm_so) Johnson, A.M. Ellen, S.D. 1968 Report prepared for Town of Portola Valley, California 2400 paper 1968 publication date Johnson and Ellen (1968) Source map for region 15 (see coverage sm_so) Lawson, A.C. 1914 U.S. Geological Survey Geological Atlas, Folio 193 62500 paper 1914 publication date Lawson (1914) Source map for region 3 (see coverage sm_so) Mack, J.E. 1959 Stanford, California Stanford University M.S. thesis 24000 paper 1959 publication date Mack (1959) Source map for region 11 (see coverage sm_so) McLaughlin, R.J. 1969 San Jose, California San Jose State College report 12000 paper 1969 publication date McLaughlin (1969) Source map for region 5 (see coverage sm_so) Pampeyan, E.H. 1970 U.S. Geological Survey Open-File Report 70 12000 paper 1970 publication date Pampeyan (1970a) Source map for region 12 (see coverage sm_so) Pampeyan, E.H. 1970 U.S. Geological Survey Open-File Report 70- 12000 paper 1970 publication date Pampeyan (1970b) Source map for region 6 (see coverage sm_so) Pampeyan, E.H. 1993 U.S. Geological Survey Miscellaneous Investigations Series Map I-2371 24000 paper 1993 publication date Pampeyan (1993) Source map for regions 6 and 12 (see coverage sm_so) Pampeyan, E.H. 1994 U.S. Geological Survey Miscellaneous Investigations Series Map I-2390 24000 paper 1994 publication date Pampeyan (1994) Source map for regions 2, 3, and 4 (see coverage sm_so) Schlocker, Julius Pampeyan, E.H. Bonilla, M.G. 1965 U.S. Geological Survey Open-File Report 65- 62500 paper 1965 publication date Schlocker and others (1965) Source map for region 10 (see coverage sm_so) Thomas, R.G. 1951 American Geophysical Union Transactions v. 32, no. 3 p. 462-465 37500 paper 1951 publication date Thomas (1951) Source map for region 9 (see coverage sm_so) Touring, R.M. 1959 Ann Arbor, Michigan University Microfilms paper 1959 publication date Touring (1959) Source map for region 14 (see coverage sm_so) Weber, G.E. Lajoie, K.R. 1980 U.S. Geological Survey Open-File Report 80-907 24000 paper 1980 publication date Weber and Lajoie (1980) Source map for region 17 (see coverage sm_so) Base Map layers were prepared from scale-stable printing negatives of the U.S. Geological Survey Palo Alto (1982 edition) and San Francisco (1978 edition) 1:100,000 topographic map, which has a 50 meter contour interval. Scanned and vectorized images were transformed from scanner coordinates to projection coordinates with digital tics placed by hand at map corners. The images were then trimmed interactively by hand using ALACARTE to conform to the area of the geologic coverages. Small mismatches at the boundaries caused by slight differences in the original scans remain in the three base map coverages. These base map layers are digital images but no information other than location is attached to the lines. The base maps are provided for reference only. Palo Alto base map San Francisco base map 1998 sm_um-dr sm_um-cu sm_um-topo The geologic map information was digitized from stable originals of the geologic maps at 1:24,000 and 1:62,500 scale. The author manuscripts (pencil on mylar) were scanned using a Altek monochrome scanner with a resolution of 800 dots per inch. The scanned images were vectorized and transformed from scanner coordinates to projection coordinates with digital tics placed by hand at quadrangle corners. The scanned lines were edited interactively by hand using ALACARTE, color boundaries were tagged as appropriate, and scanning artifacts visible at 1:24,000 were removed. The source map (see lines in coverage sm_so) subdivides the mapped region into 20 numbered sections. The authors of OFR 98-137 relied on a variety of published and unpublished sources of information to compile the map. The references and comments listed here indicate which sources of information were used by the authors to map each section. 1. Bonilla (1965). See also Hall (1965a and b). 2. Darrow (1963), modified from Pampeyan (1994), and field checking by authors. 3. Lawson (1914), extensively modified from Pampeyan (1994), and field checking by authors. 4. Jack (1969). See also Glen (1959) and Pampeyan (1994). 5. McLauglin (1969); some field checking by E.E. Brabb, 1969, and E.H. Pampeyan, 1971. 6. Pampeyan (1970b and 1993) 7. Unpublished geologic mapping by S.A. Brooks, K.F. Oles, and Eugene Borax, Union Oil Company of California, 1956, scale 1:24,000; some data from Classen (1959). Additional field work by T.W. Dibblee, Jr. 1947-49, and by E.E. Brabb, 1968-69. 8. New mapping by authors. 9. Thomas (1951) and field reconnaissance by E.E. Brabb, 1969, and E.H. Pampeyan, 1963. 10. Schlocker and other (1965), and Brown (1972). 11. Esser (1958), and Mack (1959), modified by field checking by E.E. Brabb, 1968-69. 12. Pampeyan (1970a and 1993). Some data from Dibblee ( 1966). 13. Helley and Graymer (1997). 14. Touring (1959). See also Cummings and others (1962). Bedrock geology modified from unpublished maps, scale 1:24,000, by F.J. Noble, S.A. Brooks, Eugene Borax, K.F. Oles, R. S. Fiske, H.L. Fothergill, R.N. Hacker, and J.H. van Amringe, Union Oil Company of California, 1951-57. Additional field work by T.W. Dibblee, Jr., 1947-49 and E.E. Brabb, 1958, 1968-69. 15. Dibblee (1966) and Johnson and Ellen (1968). 16. Dibblee (1966). Some data from Cummings (1960) and Cummings and others (1962). 17. Unpublished geologic mapping, scale 1:24,000 by S.A. Brooks and R.S. Fiske, Union Oil Company of California, 1956. Additional field work by T.W. Dibblee, Jr., 1947-49, J.C. Clark and E.E. Brabb, 1969-70, and T.R. Simoni, 1971. Some San Gregorio fault lines from Weber and Lajoie (1980) and Roberta Smith (written communication, 1993). See also Hall and others (1959). 18. Brabb (1960). See also Cummings and others (1962) and Brabb (1964). 19. Cummings (1960). See also Cummings and others (1962). 20. Clark (1970), Clark and Brabb (1978), and Brabb, Clark, and Throckmorton (1977). More recently Clark (1981). Bonilla (1965) Brabb (1960) Brabb (1964) Brabb and others (1977) Brown (1972) Clark (1970) Clark (1981) Clark and Brabb (1978) Classen (1959) Cummings (1960) Cummings and others (1962) Darrow (1963) Dibblee (1966) Esser (1958) Glen (1959) Hall and others (1959) Hall (1965a) Hall (1965b) Helley and Graymer (1997) Jack (1969) Johnson and Ellen (1968) Lawson (1914) Mack (1959) McLaughlin (1969) Pampeyan (1970a) Pampeyan (1970b) Pampeyan (1993) Pampeyan (1994) Schlocker and others (1965) Thomas (1951) Touring (1959) Weber and Lajoie (1980) 1914 through 1997 Vector Entity point Complete chain GT-polygon composed of chains Universal Transverse Mercator 10 0.9996 123.0 0.0 500000 0 coordinate pair 50 50 meters NAD27 Clarke 1866 6378206 294.98 SM_AS.AAT Line attributes in coverage SM_AS (Index map of assemblages in San Mateo County). USGS OFR 98-137 LTYPE Line type USGS OFR 98-137 contact, certain Boundary between two mapped units that was observed. contact, concealed Boundary between two mapped units that is concealed and its position inferred. contact, approx. located Boundary between two mapped units whose position is not precisely known. fault, certain Strike-slip fault that was observed. fault, concealed Strike-slip fault that is concealed and its position inferred. fault, concealed, queried Strike-slip fault that is concealed and ... queried? fault, approx. located Strike-slip fault whose position is not precisely known. fault, inferred Strike-slip fault whose position is inferred. reverse fault, certain Reverse fault that was observed. reverse fault, concealed Reverse fault that is concealed and its position inferred. scratch boundary Boundary used for printing a diagram. water boundary Boundary of a body of water. map boundary Boundary of the mapped area. SYMB Field used to save symbol assignments such as displayed color USGS OFR 98-137 0 3 4 5 6 SM_CORR.AAT Line attributes in coverage SM_CORR (correlation table). USGS OFR 98-137 LTYPE Line type USGS OFR 98-137 contact, certain Boundary between two mapped units that was observed. scratch boundary Boundary used for printing a diagram SM_QUAD.AAT Line attributes in coverage SM_QUAD (Index map of quadrangles in San Mateo County). USGS OFR 98-137 LTYPE Line type USGS OFR 98-137 contact, certain Boundary between two mapped units that was observed. SM_SO.AAT Line attributes in coverage SM_SO (Sources of data index map). USGS OFR 98-137 LTYPE Line type USGS OFR 98-137 leader Line drawn to associate a number with one of the smaller mapped areas, when it would be impractical to place the identifying number inside the area. map boundary, Boundary of the mapped area. SM_UM-FLT.AAT Line attributes in coverage SM_UM-FLT (Index map of faults in San Mateo County with annotation showing the names of major faults). USGS OFR 98-137 LTYPE Line type USGS OFR 98-137 fault, certain Strike-slip fault that was observed. fault, concealed Strike-slip fault that is concealed and its position inferred. fault, concealed, queried Strike-slip fault that is concealed and ... queried? fault, approx. located Strike-slip fault whose position is not precisely known. fault, inferred Strike-slip fault whose position is inferred. reverse fault, certain Reverse fault that was observed. reverse fault, concealed Reverse fault that is concealed and its position inferred. SYMB Field used to save symbol assignments such as displayed color USGS OFR 98-137 0 1 3 4 5 SM_UM-PY.AAT Line attributes in coverage SM_UM-PY (Faults, depositional contacts, and rock units in San Mateo County). USGS OFR 98-137 LTYPE Line type USGS OFR 98-137 contact, certain Boundary between two mapped units that was observed. contact, concealed Boundary between two mapped units that is concealed and its position inferred. contact, approx. located Boundary between two mapped units whose position is not precisely known. fault, certain Strike-slip fault that was observed. fault, concealed Strike-slip fault that is concealed and its position inferred. fault, concealed, queried Strike-slip fault that is concealed and ... queried? fault, inferred Strike-slip fault whose position was inferred. fault, inferred, queried Strike-slip fault whose position was inferred and ... queried? fault, approx. located Strike-slip fault whose position is not precisely known. fault, inferred Strike-slip fault whose position is inferred. reverse fault, certain Reverse fault that was observed. reverse fault, concealed Reverse fault that is concealed and its position inferred. reverse fault, approx. located Reverse fault whose position is not known with precision. scratch boundary Boundary used for printing a diagram. water boundary Boundary of a body of water. water boundary, Boundary of a body of water. The comma at the end of the value is present in the database. map boundary Boundary of the mapped area. map boundary, Boundary of the mapped area. The comma at the end of the value is present in the database. SYMB Field used to save symbol assignments such as displayed color USGS OFR 98-137 0 1 3 4 5 6 SM_UM-SR.AAT Line attributes of coverage SM_UM-SR (Strike and dip information and fold axes in San Mateo County). USGS OFR 98-137 LTYPE Line type USGS OFR 98-137 f.a., anticline, certain Fold axis of an anticline that was observed. f.a., anticline, concealed Fold axis of an anticline that is concealed and its position inferred. f.a., syncline, certain Fold axis of a syncline that was observed. f.a., syncline, concealed Fold axis of a syncline that is concealed and its position inferred. SM_CORR.PAT Point attributes for coverage SM_CORR (Correlation table for the units in this map database). USGS OFR 98-137 PTYPE Point type USGS OFR 98-137 (blank) Map boundary polygon H2O water body af Artificial fill (Historic) alf Artificial levee fill (Historic) Qhasc Artificial stream channels (Historic) Qhsc Stream channel deposits (Holocene) Qhbd Beach deposits (Holocene) Qhbm Bay mud (Holocene) Qhb Basin deposits (Holocene) Qhfp Floodplain deposits (Holocene) Qhl Natural levee deposits (Holocene) Qhaf Alluvial fan and fluvial deposits (Holocene) Qyf Younger (inner) alluvial fan deposits (Holocene) Qyfo Younger (outer) alluvial fan deposits (Holocene) Qcl Colluvium (Holocene) Qs Sand dune and beach deposits (Holocene) Qal Alluvium (Holocene) Qpaf Alluvial fan and fluvial deposits (Pleistocene) Qpaf1 Alluvial terrace deposits (Pleistocene) Qpoaf Older alluvial fan deposits (Pleistocene) Qof Coarse-grained older alluvial fan and stream terrace deposits (Pleistocene) Qmt Marine terrace deposits (Pleistocene) Qc Colma Formation (Pleistocene) QTsc Santa Clara Formation (lower Pleistocene and upper Pliocene) QTm Merced Formation (lower Pleistocene and upper Pliocene) Tp Purisima Formation (Pliocene and upper Miocene) Tptu Tunitas Sandstone Member (Pliocene) Tpl Lobitos Mudstone Member (Pliocene) Tpsg San Gregorio Sandstone Member (Pliocene) Tpp Pomponio Mudstone Member (Pliocene) Tpt Tahana Member (Pliocene and upper Miocene) Tsc Santa Cruz Mudstone (upper Miocene) Tsm Santa Margarita Sandstone (upper Miocene) Tl Ladera Sandstone (upper(?) and middle Miocene) Tm Monterey Formation (middle Miocene) Tlo Lompico Sandstone (middle Miocene) Tpm Page Mill Basalt (middle Miocene) Tuv Unnamed Sedimentary and Volcanic Rocks (Miocene and Oligocene) Tls Lambert Shale and San Lorenzo Formation, Undivided (lower Miocene, Oligocene, and middle and upper Eocene) Tla Lambert Shale (Oligocene and lower Miocene) Tmb Mindego Basalt and related volcanic rocks (Miocene and/or Oligocene) Tvq Vaqueros Sandstone (lower Miocene and Oligocene) Tsl San Lorenzo Formation (Oligocene and upper and middle Eocene) Tsr Rices Mudstone Member (Oligocene and upper Eocene) Tst Twobar Shale Member (middle and upper Eocene) Tb Butano Sandstone (middle and lower Eocene) Tbs Shale in Butano Sandstone (lower Eocene) Tw Whiskey Hill Formation (middle and lower Eocene) Tws Shale in Whiskey Hill Formation (lower Eocene) Tss Unnamed sandstone, shale, and conglomerate (Paleocene) Kpp Pigeon Point Formation (Upper Cretaceous) Ksh Unnamed shale (Upper Cretaceous) Ka Anchor Bay Conglomerate (Cretaceous) Ks Unnamed sandstone and shale (Cretaceous?) Kgr Granitic rocks of Montara Mountain KJv Unnamed volcanic rocks (Cretaceous or older) KJs Unnamed sandstone (Cretaceous or Jurassic) KJf Franciscan Complex, undivided (Cretaceous and Jurassic) fs Sandstone fg Greenstone fc Chert fl Limestone fm Metamorphic rocks fcg Conglomerate fsr Sheared rock (melange) sp Serpentinite (Cretaceous and/or Jurassic) Jsv Siliceous volcanic rocks and keratophyre (Jurassic?) Jgb Gabbro (Jurassic?) m Marble and hornfels (Paleozoic?) SM_UM-PY.PAT Polygon attributes for coverage SM_UM-PY (Faults, depositional contacts, and rock units in San Mateo County). USGS OFR 98-137 PTYPE Polygon type USGS OFR 98-137 (blank) Map boundary polygon H2O water body af Artificial fill (Historic) alf Artificial levee fill (Historic) Qhasc Artificial stream channels (Historic) Qhsc Stream channel deposits (Holocene) Qhbd Beach deposits (Holocene) Qhbm Bay mud (Holocene) Qhb Basin deposits (Holocene) Qhfp Floodplain deposits (Holocene) Qhl Natural levee deposits (Holocene) Qhaf Alluvial fan and fluvial deposits (Holocene) Qyf Younger (inner) alluvial fan deposits (Holocene) Qyfo Younger (outer) alluvial fan deposits (Holocene) Qcl Colluvium (Holocene) Qs Sand dune and beach deposits (Holocene) Qal Alluvium (Holocene) Qpaf Alluvial fan and fluvial deposits (Pleistocene) Qpaf1 Alluvial terrace deposits (Pleistocene) Qpoaf Older alluvial fan deposits (Pleistocene) Qof Coarse-grained older alluvial fan and stream terrace deposits (Pleistocene) Qmt Marine terrace deposits (Pleistocene) Qc Colma Formation (Pleistocene) QTsc Santa Clara Formation (lower Pleistocene and upper Pliocene) QTm Merced Formation (lower Pleistocene and upper Pliocene) Tp Purisima Formation (Pliocene and upper Miocene) Tptu Tunitas Sandstone Member (Pliocene) Tpl Lobitos Mudstone Member (Pliocene) Tpsg San Gregorio Sandstone Member (Pliocene) Tpp Pomponio Mudstone Member (Pliocene) Tpt Tahana Member (Pliocene and upper Miocene) Tsc Santa Cruz Mudstone (upper Miocene) Tsm Santa Margarita Sandstone (upper Miocene) Tl Ladera Sandstone (upper(?) and middle Miocene) Tm Monterey Formation (middle Miocene) Tlo Lompico Sandstone (middle Miocene) Tpm Page Mill Basalt (middle Miocene) Tuv Unnamed Sedimentary and Volcanic Rocks (Miocene and Oligocene) Tls Lambert Shale and San Lorenzo Formation, Undivided (lower Miocene, Oligocene, and middle and upper Eocene) Tla Lambert Shale (Oligocene and lower Miocene) Tmb Mindego Basalt and related volcanic rocks (Miocene and/or Oligocene) Tvq Vaqueros Sandstone (lower Miocene and Oligocene) Tsl San Lorenzo Formation (Oligocene and upper and middle Eocene) Tsr Rices Mudstone Member (Oligocene and upper Eocene) Tst Twobar Shale Member (middle and upper Eocene) Tb Butano Sandstone (middle and lower Eocene) Tbs Shale in Butano Sandstone (lower Eocene) Tw Whiskey Hill Formation (middle and lower Eocene) Tws Shale in Whiskey Hill Formation (lower Eocene) Tss Unnamed sandstone, shale, and conglomerate (Paleocene) Kpp Pigeon Point Formation (Upper Cretaceous) Ksh Unnamed shale (Upper Cretaceous) Ka Anchor Bay Conglomerate (Cretaceous) Ks Unnamed sandstone and shale (Cretaceous?) Kgr Granitic rocks of Montara Mountain KJv Unnamed volcanic rocks (Cretaceous or older) KJs Unnamed sandstone (Cretaceous or Jurassic) KJf Franciscan Complex, undivided (Cretaceous and Jurassic) fs Sandstone fg Greenstone fc Chert fl Limestone fm Metamorphic rocks fcg Conglomerate fsr Sheared rock (melange) sp Serpentinite (Cretaceous and/or Jurassic) Jsv Siliceous volcanic rocks and keratophyre (Jurassic?) Jgb Gabbro (Jurassic?) m Marble and hornfels (Paleozoic?) SM_UM-SR.PAT Point features in coverage SM_UM-SR USGS OFR 98-137 PTTYPE Type of point feature USGS OFR 98-137 bedding A depositional surface flat bedding A flat depositional surface foliation A surface of metamorphic origin joint Planar fractures ot bedding Overturned bedding (older rocks on top) vert bedding Vertical bedding surface vert foliation and bedding Vertical foliation parallel to bedding vert joint Vertical planar fractures DIP Measured structural dip of planar features at the point USGS OFR 98-137 0 90 degrees 1 STRIKE Measured structural strike of planar features at the point. USGS OFR 98-137 0 359 degrees 1 The databases in this report were compiled in ARC/INFO, a commercial Geographic Information System (Environmental Systems Research Institute, Redlands, California), with version 3.0 of the menu interface ALACARTE (Fitzgibbon and Wentworth, 1991, Fitzgibbon, 1991, Wentworth and Fitzgibbon, 1991). Consequently each feature attribute table contains attributes generated by the software to describe the topology of the geographic features. In addition, the following integer fields are included by ALACARTE: >SEL user defined field used to save a selected set >SYMB user defined field used to save symbol assignments (such as color) The geologic linetypes are ALACARTE line types that correlate with the geologic line symbols in the ALACARTE line set GEOL61.LIN according to the ALACARTE lines lookup table (GEOL61.LUT). USGS Open-File Report 98-137 file smdb.txt San Mateo County Geologic Database Database coordinator mailing and physical address

345 Middlefield Road, MS 975

Menlo Park CA 94025 USA 650-329-4921 rgraymer@usgs.gov USGS Open-File Report 98-137 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 San Mateo 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. ArcInfo export 7.0.4 >ARC/INFO coverages >sm_um-py.e00 Faults, depositional contacts, and rock units >sm_um-sr.e00 Strike and dip information and fold axes >sm_quad.e00 Index map of quadrangles >sm_um-flt.e00 Index map of faults >sm_corr.e00 Correlation table for the units >sm_so.e00 Sources of data index map >sm_as.e00 Index map of Assemblages >sm_um-dr.e00 Drainage base map >sm_um-cu.e00 Cultural base map >sm_um-topo.e00 Topographic contours base map gzip and tar 5.4 megabytes http://pubs.usgs.gov/of/1998/of98-137/sm_g1.tar.gz none The map can be downloaded as a 5.5 megabyte PDF file from http://pubs.usgs.gov/of/1998/of98-137/smmap.pdf The explanation sheet can be downloaded as a 1.2 megabyte PDF file from http://pubs.usgs.gov/of/1998/of98-137/smexpl.pdf none Database files, PostScript plotfiles, and related files can be obtained by sending a tape or CDR (Recordable CD-ROM) with request and return address to: >San Mateo County Geologic Database >c/o Database Coordinator >U.S. Geological Survey >345 Middlefield Road, M/S 975 >Menlo Park, CA 94025 Do 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 or CD-ROM. The acceptable tape type is: 2.3 or 5.0 GB, 8 mm Exabyte tape. 19981217 Peter N. Schweitzer U.S. Geological Survey mailing and physical address

12201 Sunrise Valley Drive, Mail Stop 918

Reston VA 20192 USA 703-648-6533 703-648-6560 pschweitzer@usgs.gov Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998 http://geology.usgs.gov/tools/metadata/tools/ext/parts.ext