Metadata: Identification_Information: Citation: Citation_Information: Originator: E.J. Helley Originator: R.W. Graymer Publication_Date: 1997 Title: Quaternary geology of Alameda County, and parts of Contra Costa, Santa Clara, San Mateo, San Francisco, Stanislaus, and San Joaquin Counties, California: A digital database Geospatial_Data_Presentation_Form: map Series_Information: Series_Name: U.S. Geological Survey Open-File Report Issue_Identification: 97-97 Online_Linkage: http://pubs.usgs.gov/of/1997/0097/ Description: Abstract: Alameda County is located at the northern end of the Diablo Range of Central California. It is bounded on the north by the south flank of Mount Diablo, one of the highest peaks in the Bay Area, reaching an elevation of 1173 meters (3,849 ft). San Francisco Bay forms the western boundary, the San Joaquin Valley borders it on the east and an arbitrary line from the Bay into the Diablo Range forms the southern boundary. Alameda is one of the nine Bay Area counties tributary to San Francisco Bay. Most of the country is mountainous with steep rugged topography. Alameda County is covered by twenty-eight 7.5' topographic Quadrangles which are shown on the index map (alq_quad or Sheet 2). The Quaternary deposits in Alameda County comprise three distinct depositional environments. One, forming a transgressive sequence of alluvial fan and fan-delta facies, is mapped in the western one-third of the county. The second, forming only alluvial fan facies, is mapped in the Livermore Valley and San Joaquin Valley in the eastern part of the county. The third, forming a combination of Eolian dune and estuarine facies, is restricted to the Alameda Island area in the northwestern corner of the county. Purpose: To provide to the public a digital geologic map database of the Alameda county and parts of Contra Costa, Santa Clara, San Mateo, San Francisco, Stanislaus, and San Joaquin counties, California. Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1997 Currentness_Reference: publication date Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -122.38 East_Bounding_Coordinate: -121.38 North_Bounding_Coordinate: 38.0 South_Bounding_Coordinate: 37.38 Access_Constraints: none Use_Constraints: none Keywords: Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: geology Theme_Keyword: geologic maps Theme_Keyword: surficial geologic units Theme_Keyword: unconsolidated deposits Theme_Keyword: geologic history Theme_Keyword: geologic structure Theme_Keyword: geospatial datasets Theme: Theme_Keyword_Thesaurus: National Geologic Map Database Catalog themes, augmented Theme_Keyword: 3400 - Graphical Theme_Keyword: 3100 - Vector Theme_Keyword: 3420 - PostScript Theme_Keyword: 3110 - ESRI Theme_Keyword: 3112 - export Theme_Keyword: 1100 - Geology Theme_Keyword: 1101 - General Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Categories Theme_Keyword: geoscientificInformation Place: Place_Keyword_Thesaurus: Augmented FIPS 10-4 and FIPS 6-4 Place_Keyword: f06001 = Alameda Place_Keyword: f06013 = Contra Costa Place_Keyword: f06081 = San Mateo Place_Keyword: f06075 = San Francisco Place_Keyword: f06085 = Santa Clara Place_Keyword: f06077 = San Joaquin Place_Keyword: f06099 = Stanislaus Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Graymer, Russell W Contact_Organization: USGS-GEO-WRG-NGM Contact_Address: Address_Type: mailing and physical address Address: Mail Stop 975, USGS 345 Middlefield Road City: Menlo Park State_or_Province: CA Postal_Code: 94025 Country: US Contact_Voice_Telephone: 650-329-4988 Contact_Electronic_Mail_Address: rgraymer@usgs.gov Browse_Graphic: Browse_Graphic_File_Name: http://pubs.usgs.gov/of/1997/0097/pdf/alqmap.pdf Browse_Graphic_File_Description: PDF representation of the geologic map sheet Browse_Graphic_File_Type: PDF Data_Set_Credit: Carl M. Wentworth, Todd T. Fitzgibbon, and Geoffrey A. Phelps graciously provided assistance with Alacarte and ARC/INFO. The scanning and initial editing of the digital maps of some of the quadrangles was done by the following: Heather Schoonover (Midway, Newark), Marjorie Lucks (Livermore), Scott Graham (Altamont), Lisa Gerhardt (San Leandro), Jennifer Tarsoly (Hayward), Carolyn Randolph (Hunters Point, Redwood Point), Molly Burgett (Oakland West), Michelle Roberts (Niles, La Costa Valley). Earl E. Brabb provided much helpful advice and feedback, as well as arranging for material support for the project. Native_Data_Set_Environment: ARC/INFO version 7.0.3 Data_Quality_Information: Logical_Consistency_Report: This digital map database, compiled from previously unpublished data, and new mapping by the authors, represents the general distribution of surficial deposits in Alameda County and surrounding areas. Completeness_Report: No bedrock units have been mapped; bedrock outcrop is simply labeled "br". Other geologic features, such as folds and faults, have not been mapped. A few large landslides are shown, but this map does not show most of the landslides in the area. Lineage: Process_Step: Process_Description: MAPPING METHODS Geological units were mapped on 1:24,000 scale U.S. Geological Survey topographic maps using 1939 black and white aerial photographs showing the county before much development had taken place. The mapping was supplemented with 1:12,000- and 1:24,000-scale color aerial photography flown in 1965 and 1974 respectively. The mapping was also aided by observations made on turn of the century topographic maps at 1:62,500-scale with 25 foot (7.6 m) contour intervals. These maps were most useful in recognizing natural stream channels which have since been modified. The position of water boundaries, the stream channel to water transition, the length and position of mapped stream channels (see below), the distribution of artificial levees, and the apparent distribution of artificial fill were plotted to conform with the most recent 1:24,000 scale topographic maps. Mapping units were delineated by: 1) landform morphology, 2) relative topographic position, 3) relative preservation of surface morphology, 4) tonal contrasts on aerial photographs, 5) relative soil profile development (compiled from the U.S. Soil Conservation Service, 1917), and 6) other features such as differences in vegetation density and type. Landform morphology refers to the shape of a particular landscape element. Examples are the distinctive conical shape of alluvial fans and the shape of levees that usually border active stream channels, sloping away from them to blend into flat basin deposits. Other criteria listed in the description of geological units are also used to distinguish one element from another, but they are particularly useful for delineating units within a specific landscape element. A surface on an alluvial fan, for example, might be differentiated from another because of its higher topographic position, greater drainage density, and stronger soil profile development. Geologic units defined this way are called allostratigraphic units (American Association of Petroleum Geologists Bulletin, 1983). Digital Compilation The geologic map information was digitized from stable originals of the geologic maps at 1:24,000 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. Base Maps Base Map layers were prepared from scale-stable printing negatives of the U.S. Geological Survey San Francisco (1978 edition), Stockton (1989 edition), Palo Alto (1983 edition), and San Jose (1978 edition) 1:100,000 topographic maps, which have 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, and the four portions were combined. 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. Process_Date: unknown Process_Step: Process_Description: Creation of original metadata record Process_Date: 20000814 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Jennifer Lenz Contact_Organization: US Geological Survey Contact_Address: Address_Type: mailing Address: 12201 Surise Valley Drive, Mail Stop 918 City: Reston State_or_Province: VA Postal_Code: 20192 Country: USA Contact_Voice_Telephone: 703-648-6974 Contact_Facsimile_Telephone: 703-648-6560 Contact_Electronic_Mail_Address: pschweitzer@usgs.gov Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: vector Point_and_Vector_Object_Information: SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: entity point SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: complete chain SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: GT-polygon composed of chains Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: California state plane coordinate system State_Plane_Coordinate_System: SPCS_Zone_Identifier: 3426 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: coordinate pair Planar_Distance_Units: meters Entity_and_Attribute_Information: Overview_Description: Entity_and_Attribute_Overview: >ARC/INFO export files Description of coverage > >at_sp-py.e00 Quaternary deposits of the Altamont quadrangle >bh_sp-py.e00 Byron Hot Springs quadrangle >cf_sp-py.e00 Clifton Court Forebay quadrangle >cm_sp-py.e00 Cedar Mtn quadrangle >cr_sp-py.e00 Calaveras Reservoir quadrangle >du_sp-py.e00 Dublin quadrangle >em_sp-py.e00 Eylar Mtn quadrangle >ha_sp-py.e00 Hayward quadrangle >hp_sp-py.e00 Hunters Point quadrangle >lc_sp-py.e00 La Costa Valley quadrangle >lt_sp-py.e00 Las Trampas Ridge quadrangle >lv_sp-py.e00 Livermore quadrangle >mb_sp-py.e00 Mt Boardman quadrangle >md_sp-py.e00 Mt Day quadrangle >mp_sp-py.e00 Milpitas quadrangle >ms_sp-py.e00 Mendenhall Springs quadrangle >mv_sp-py.e00 Mountain View quadrangle >mw_sp-py.e00 Midway quadrangle >ne_sp-py.e00 Newark quadrangle >ni_sp-py.e00 Niles quadrangle >oe_sp-py.e00 Oakland East quadrangle >ow_sp-py.e00 Oakland West quadrangle >ri_sp-py.e00 Richmond quadrangle >rp_sp-py.e00 Redwood Point quadrangle >sl_sp-py.e00 San Leandro quadrangle >ta_sp-py.e00 Tassajara quadrangle >alq_quad.e00 Index map of quadrangles in Alameda County >alq_corr.e00 Correlation table for the units in this map database >al_dr-sp.e00 Drainage base map >al_cu-sp.e00 Cultural base map >al_topo-sp.e00 Topographic contours base map Entity_and_Attribute_Detail_Citation: http://pubs.usgs.gov/of/1997/0097/pdf/alqgeo.pdf Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: XX_SP-PY.PAT (XX represents the two-letter symbol for each of the quadrangles) Entity_Type_Definition: Quaternary geology map units Entity_Type_Definition_Source: OFR-97-97 Attribute: Attribute_Label: PTYPE Attribute_Definition: Polygon type Attribute_Definition_Source: OFR-97-97 Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: af Enumerated_Domain_Value_Definition: Artificial Fill (Historic) Enumerated_Domain: Enumerated_Domain_Value: alf Enumerated_Domain_Value_Definition: Artificial Levee Fill (Historic) Enumerated_Domain: Enumerated_Domain_Value: br Enumerated_Domain_Value_Definition: bedrock deposits Enumerated_Domain: Enumerated_Domain_Value: GP Enumerated_Domain_Value_Definition: Gravel Pits (Historic) Enumerated_Domain: Enumerated_Domain_Value: Qhasc Enumerated_Domain_Value_Definition: Artificial Stream Channels (Historic) Enumerated_Domain: Enumerated_Domain_Value: Qhbm Enumerated_Domain_Value_Definition: Bay Mud (Holocene) Enumerated_Domain: Enumerated_Domain_Value: Qhpm Enumerated_Domain_Value_Definition: Peat and Peaty mud (Holocene) Enumerated_Domain: Enumerated_Domain_Value: Qhsc Enumerated_Domain_Value_Definition: Stream Channel Deposits (Holocene) Enumerated_Domain: Enumerated_Domain_Value: Qhl Enumerated_Domain_Value_Definition: Natural Levee Deposits (Holocene) Enumerated_Domain: Enumerated_Domain_Value: Qhfp1 Enumerated_Domain_Value_Definition: Alluvial terrace - first erosional terrace (Holocene) Enumerated_Domain: Enumerated_Domain_Value: Qhfp2 Enumerated_Domain_Value_Definition: Alluvial terrace - second erosional terrace (Holocene) Enumerated_Domain: Enumerated_Domain_Value: Qhb Enumerated_Domain_Value_Definition: Basin Deposits (Holocene) Enumerated_Domain: Enumerated_Domain_Value: Qhbs Enumerated_Domain_Value_Definition: Floodbasin Deposits (salt-affected) (Holocene) Enumerated_Domain: Enumerated_Domain_Value: Qhbr Enumerated_Domain_Value_Definition: Beach Ridge Deposits (Holocene) Enumerated_Domain: Enumerated_Domain_Value: Qhaf1 Enumerated_Domain_Value_Definition: Younger Alluvial Fan Deposits (Holocene) Enumerated_Domain: Enumerated_Domain_Value: Qhaf Enumerated_Domain_Value_Definition: Alluvial Fan and Fluvial Deposits (Holocene) Enumerated_Domain: Enumerated_Domain_Value: Qms Enumerated_Domain_Value_Definition: Merritt Sand (Pleistocene and Holocene) Enumerated_Domain: Enumerated_Domain_Value: Qls Enumerated_Domain_Value_Definition: Landslide deposits (Pleistocene and/or Holocene) Enumerated_Domain: Enumerated_Domain_Value: Qpaf Enumerated_Domain_Value_Definition: Alluvial Fans and Fluvial Deposits (Pleistocene) Enumerated_Domain: Enumerated_Domain_Value: Qpaf1 Enumerated_Domain_Value_Definition: Alluvial Terrace Deposits (Pleistocene) Enumerated_Domain: Enumerated_Domain_Value: Qpaf2 Enumerated_Domain_Value_Definition: Pleistocene alluvial terraces Enumerated_Domain: Enumerated_Domain_Value: Qmt Enumerated_Domain_Value_Definition: Marine Terrace Deposits (Pleistocene) Enumerated_Domain: Enumerated_Domain_Value: Qpoaf Enumerated_Domain_Value_Definition: Older Alluvial Fan deposits (Pleistocene) Enumerated_Domain: Enumerated_Domain_Value: QTl Enumerated_Domain_Value_Definition: Livermore gravels (Pliocene and Pleistocene) Enumerated_Domain: Enumerated_Domain_Value: QTi Enumerated_Domain_Value_Definition: Irvington Gravels of Savage (1951) (Pliocene(?) and Pleistocene) Enumerated_Domain: Enumerated_Domain_Value: QTp Enumerated_Domain_Value_Definition: Packwood Gravels of Crittenden (1951) (Pliocene and Pleistocene) Enumerated_Domain: Enumerated_Domain_Value: H20 Enumerated_Domain_Value_Definition: Body of water Detailed_Description: Entity_Type: Entity_Type_Label: XX_SP-PY.AAT (XX represents the two-letter symbol for each of the quadrangles) Entity_Type_Definition: Linear geologic features Entity_Type_Definition_Source: OFR-97-97 Attribute: Attribute_Label: LTYPE Attribute_Definition: Line type Attribute_Definition_Source: OFR-97-97 Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: contact, approx. located Enumerated_Domain_Value_Definition: Contact whose position is not precisely known Enumerated_Domain: Enumerated_Domain_Value: contact, certain Enumerated_Domain_Value_Definition: Observed contact Enumerated_Domain: Enumerated_Domain_Value: contact, concealed Enumerated_Domain_Value_Definition: Concealed contact whose position is inferred Enumerated_Domain: Enumerated_Domain_Value: contact, inferred Enumerated_Domain_Value_Definition: Contact whose position is inferred Enumerated_Domain: Enumerated_Domain_Value: map boundary Enumerated_Domain_Value_Definition: Boundary of mapped area Enumerated_Domain: Enumerated_Domain_Value: water boundary Enumerated_Domain_Value_Definition: Boundary around body of water Enumerated_Domain: Enumerated_Domain_Value: (blank) Enumerated_Domain_Value_Definition: unknown Detailed_Description: Entity_Type: Entity_Type_Label: XX_SP-PY.PAT (XX represents the two-letter symbol for each of the quadrangles) Entity_Type_Definition: Quaternary geologic map units at specific locations (same attributes as polygon coverage of the same name) Entity_Type_Definition_Source: OFR-97-97 Detailed_Description: Entity_Type: Entity_Type_Label: ALQ_CORR.PAT Entity_Type_Definition: Correlation table for the units in this map database (same attributes as polygon coverage XX_SP-PY.PAT) Entity_Type_Definition_Source: OFR-97-97 Detailed_Description: Entity_Type: Entity_Type_Label: ALQ_CORR.AAT Entity_Type_Definition: Correlation table for the units in this map database (same attributes as arc coverage XX_SP-PY.AAT) Entity_Type_Definition_Source: OFR-97-97 Detailed_Description: Entity_Type: Entity_Type_Label: ALQ_CORR.PAT Entity_Type_Definition: Correlation table for the units in this map database (same attributes as polygon coverage XX_SP-PY.PAT) Entity_Type_Definition_Source: OFR-97-97 Detailed_Description: Entity_Type: Entity_Type_Label: ALQ_QUAD.AAT Entity_Type_Definition: Index map of quadrangles in Contra Costa County (same attributes as arc coverage XX_SP-PY.AAT) Entity_Type_Definition_Source: OFR-97-97 Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: USGS Information Services Contact_Address: Address_Type: mailing Address: Box 25286, Denver Federal Center City: Denver State_or_Province: Colorado Postal_Code: 80255-0046 Country: USA Contact_Voice_Telephone: 1-888-ASK-USGS Contact_Facsimile_Telephone: 1-303-202-4695 Contact_Electronic_Mail_Address: infoservices@usgs.gov Resource_Description: US Geological Survey Open-File Report 97-97 Distribution_Liability: 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 "Quaternary geology of Alameda County, and parts of Contra Costa, Santa Clara, San Mateo, San Francisco, Stanislaus, and San Joaquin Counties, 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. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: ARCE Format_Version_Number: 7.x Format_Information_Content: Quaternary geologic units and base map information File_Decompression_Technique: gzip and tar Transfer_Size: 19.5 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://pubs.usgs.gov/of/1997/0097/al_q1.tar.Z Fees: none Metadata_Reference_Information: Metadata_Date: 20160610 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Peter N Schweitzer Contact_Organization: USGS Midwest Area Contact_Position: Collection manager, USGS Geoscience Data Clearinghouse, http://geo-nsdi.er.usgs.gov/ Contact_Address: Address_Type: mailing address Address: Mail Stop 954 12201 Sunrise Valley Dr City: Reston State_or_Province: VA Postal_Code: 20192-0002 Country: USA Contact_Voice_Telephone: 703-648-6533 Contact_Facsimile_Telephone: 703-648-6252 Contact_Electronic_Mail_Address: pschweitzer@usgs.gov Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998