Preliminary geologic map of the San Francisco South 7.5' quadrangle and part of the Hunters Point 7.5' quadrangle, San Francisco Bay area, California: A digital database

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Description This Open-File report is a digital geologic map database of the San Francisco South 7.5' quadrangle. This pamphlet serves to introduce and describe the digital data. No paper map is included in the Open-File report, however this report includes a PostSc
Originators Bonilla, M. G.
Publication U.S. Geological Survey Open-File Report 98-354

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Overview of attributes

The data is supplied in two formats.  The first is the Microsoft-PC based native GSMCAD format and the second is a UNIX based ARC/INFO format.
DATABASE FILES - GSMCAD (DOS) ====================================
Text file of the description of map units and discussion of deposits, structure, and geologic history.  Unit descriptions can be accessed by selecting map unit symbols displayed on screen.
Mesquite.lsf, .ndx, and .nod
The basic database components of line segment file, index file, and node file for the map.  Units are degrees of latitude and longitude
Unitlist.lsf, .ndx, and .nod
The basic database components for the explanation sheet.  Units are inches
File of plotting parameters for the map
File of plotting parameters for the explanation sheet
File of projection parameters for the Transverse Mercator projection of the  1:24,000 scale 7 1/2 ' Mesquite topographic quadrangle basemap
File of projection parameters for the Universal Transverse Mercator (zone 11) projection of a 1:100,000 scale 1 degree by 30 minute Overton sheet basemap.  This can be used in GSMCAD to export UTM ground meters.
Text file listing all map unit symbols
Text file listing the explanations of the graphic symbols on the map
Text file listing all the age names, headers, and other text used on the correlation of map units diagram, except for the map unit symbols
Text file listing the names of map units
Text file containing selected field notes that are linked to the observation points in the map database (code 197)
Table of locations of selected water wells in the map area that can optionally be plotted on the map
DATABASE STRUCTURE - ARC/INFO ====================================
The database of the map consists of four coverages (root name Mesquite) and four additional info files.  There are also four parallel coverages (rootname mesqexpl) that make up an explanation sheet with a correlation of map units diagram, list of map unit symbols and names, and an explanation of symbols.
Mesquitepoly coverage:  Contains all contact lines and labelpoints for each polygon.  The CODE item defines the significance of the lines as listed above and in the gsmcode.lut INFO file.  The P1 item defines the category of polygon as listed above and in the gsmunit.lut INFO file.
Mesquiteline coverage:  Contains faults, fold axis, and other non-contact lines.  Faults that are contacts also appear in the Mesquitepoly coverage.  The CODE item defines the significance of the lines as listed above and in the gsmcode.lut INFO file.
Mesquitesym coverage:  Contains points recording observations, such as strike and dip of bedding, points for posting of dip or plunge values associated with the observation points, and arcs that draw out the symbols associated with the observation points and the symbols used to decorate certain lines. The CODE item defines the type of observation as listed above and in the gsmcode.lut INFO file.  For rotational observations (CODE 200 to 299) the P1 item is the azimuth (strike) and the P2 item is the inclination (dip).  The item gsmentity contains a unique number for each observation that ties together the observation point, posting point, and arcs that represent a single observation.  That number is negative for the posting point to distinguish it from the observation point.
Mesquitetext coverage: Contains text points that define the position, rotation, and size of text to appear on the face of the map.  Also includes arcs that draw leaders from the text to the appropriate polygons.  This coverage is for cartographic purposes and does not include data critical to the database information.  The P1 item defines rotation of the text, the P2 item the size of text, and the TEXT item the actual text.
Gsmrelate INFO file:  Contains the information that relates the gsmcode.lut and gsmunit.lut to the pat and aat INFO files of the coverages
Gsmunit.lut INFO file:  Contains the first two columns of the table above that lists the number (P1 item) assigned to each category of polygon and the corresponding text symbol used in the map explanation and on the face of the map.  The database can be made more useful by expanding this file to include items listing characteristics, age, etc. of each geologic unit, and that should be done before a final version is released.
Gsmcode.lut INFO file:  Contains a text definition of the meaning of the number stored in the CODE item of every entity in all the coverages. INFO file:  Assigns a color from shadeset CTR269.shd for each category of polygon according to the P1 item.
Auxiliary files:
Gsmdraw.aml and gsmdraw.mnu files are included to constitute an ARC/INFO macro language program that will extract information from the Mesquite coverages to produce a graphics (.gra) file depicting the Mesquite geologic map.  The graphics file can be viewed on screen or plotted with appropriate equipment.
The aml program calls shadeset ctr269.shd, font font003, and lineset alcwrg.lin, so these are also included in the archive file.  Other files can be substituted, but special geologic characters may not plot properly with a different font.

Database root name: MESQUITE >P1 VALUE AND LETTER SYMBOLS FOR GEOLOGIC UNITS MAPPED======= > >1,Qfp, Flood-plain alluvium >2,Qrm, Recent mainstream alluvium >3,Qim, Intermediate-age mainstream alluvium >4,Qom, Old mainstream alluvium >5,Trm, Tertiary mainstream alluvium >6,Trs, Tertiary sidestream alluvium >10,Qs, Channel alluvium >35,Qiz, Intermediate-age mainstream alluvium, sand and silt facies >46,af, Artificial fill and other land disturbance >47,Tms, Muddy Creek Formation >48,Tmc, Muddy Creek Formation conglomerate facies >53,Qis, Intermediate-age sidestream alluvium >54,Trs, Tertiary sidestream alluvium >56,Qos, Old sidestream alluvium >148,Trs, Tertiary sidestream alluvium (pediment on Muddy Creek Formation) >150,Qos, Old side-stream alluvium (pediment on Muddy Creek Formation) >152,Tok, Old Tertiary calcrete >153,Qe, Windblown sand >161,Qc, Colluvium >167,Ql, Landslide deposits >173,Qrs, Recent sidestream alluvium >177,Qym, Young mainstream alluvium >179,Qys, Young sidestream alluvium >193,Qok, Old Pleistocene calcrete >200,Tik, Intermediate-age Tertiary calcrete >201,Trk, Young Tertiary calcrete >218,Tb, Tertiary basalt lava flow and ash >219,Tf, Post-Muddy Creek Tertiary basin-fill sediments > >FEATURES IN THE DATABASE------------------------- > >CODE | FEATURE >001 | Geologic contacts >008 | Normal fault -certain >009 | Normal fault - approximately located >010 | Normal fault - concealed >011 | Basaltic ash marker bed line >020 | Fold axis lines >054 | Roads >061 | Map boundary >197 | Field observation point symbol >201 | bedding dip symbol >204 | anticline symbol >205 | syncline symbol >207 | ball & bar symbol >208 | fault dip symbol >255 | monocline - anticline symbol >256 | monocline - syncline symbol >313 | gravel pit symbol >375 | water well symbol >501 | geologic unit tag point >555 | geologic unit tag point and text label >599 | Map margin text