Search for geospatial/GIS data

Find GIS data held at MIT and other institutions

421 results returned

  1. Title: Cover Types of the UMN Cloquet Forestry Center, 2021 {Cloquet, Minnesota}

    Contributors:

    Summary: Cover Types of the UMN Cloquet Forestry Center, 2021 is a polygon representation of forest stands and other vegetation types across the 3400-acre research forest. Polygon attributes represent the current status of forest inventory records for the CFC at the end of 2021 based on episodic updates to an original 2005 cover type mapping product. The University of Minnesota (UMN) Cloquet Forestry Center is a field research and instructional station associated with the College of Food, Agricultural, and Natural Resources Sciences (CFANS). The original dataset (shapefile) inventorying forest cover types at the University of Minnesota Cloquet Forestry Center was an outcome of a 2005 Covertype Mapping Project produced by Brian C. Loeffelholz and Guthrie Zimmerman on behalf of the UMN Department of Forest Resources (https://hdl.handle.net/11299/120191). The data provided here represents episodic updates to the 2005 covertype shapefile since that time. Forest stand boundaries, stand attributes, and attribute fields have been modified by Cloquet Forestry Center staff through 2021 to reflect spatial and temporal changes to cover types over time and from various management actions, predominately timber harvests.

    View full record

  2. Title: Maps of wind-wave height on Minnesota lake shorelines

    Contributors:

    Summary: This data set provides maps of typical wind-wave height and energy on Minnesota lakes to inform shoreline and near-shore habitat restoration projects. The data set consists of a set of ArcMap shape files which map out simulated wave height and energy parameters for a series of points around the shoreline of 460 lakes in Minnesota, with separate files for annual wave statistics and monthly wave statistics. The wave statistics were calculated for each lake based on airport wind data and the open water distance (fetch) across the lake for each wind direction. Each shapefile contains information on multiple wave statistics, including the mean and significant wave height, the number of days wave height exceeds thresholds, and cumulative wave energy over the time period. There are a total of 11 shapefiles in this data set, including one file for annual wave statistics (Annual_WaveStats), 9 files for monthly wave statistics for April through December (e.g. April_WaveStats.shp) , and a shapefile giving the lake polygons for the 460 Minnesota lakes included in this study (Study_Lakes.shp). Each shapefile is packaged for download in .zip format.

    View full record

  3. Title: San Francisco Outline

    Contributors:

    Summary: This data layer is a mask covering the San Francisco mainland up to the county line, Treasure Island, and Yerba Buena Island.

    View full record

  4. Title: Johnson's new military map of the United States showing the forts, military posts & all the military divisions with enlarged plans of southern harbors; from authentic data obtained at the War Department, Washington; Johnson & Browning.

    Contributors:

    Summary: Relief shown by hachures. Prime meridians: Greenwich and Washington, D.C. Insets: New Orleans and delta of Mississippi, Louisiana -- Mobile Bay, Alabama -- Entrance to Pensacola Bay, Florida -- Key West, Florida -- Savannah River -- Charleston Harbor, S. Carolina -- Hampton Roads and Norfolk Harbor, Virginia -- Washington and vicinity -- Baltimore and vicinity. Possibly from Johnson's New Illustrated (Steel Plate) Family Atlas, With Physical Geography, And With Descriptions Geographical, Statistical, And Historical. "Entered according to Act of Congress in the year one thousand eight hundred & sixty one by Johnson & Browning in the Clerk's office of the District Court of the United States for the southern Distrct of New York." 1 map: hand col.; 31 x 49 cm., on sheet 46 x 66 cm.

    View full record

  5. Title: Johnson's Minnesota and Dakota

    Contributors:

    Summary: Atlas plate 52. Longitude west from Greenwich and Washington, D.C. 12.5 x 15.5 inches General Minnesota Maps

    View full record

  6. Title: Johnson's New York; by Johnson & Browning.; New York

    Contributors:

    Summary: Relief shown by hachures. Shows county boundaries and township boundaries. Prime meridians: Greenwich and Washington. Map within decorative border. In upper margin: 27. Insets: Oswego -- Albany -- Troy -- Vicinity of New York -- Buffalo -- Rochester -- Syracuse. 1 map: hand col.; 42 x 60 cm.

    View full record

  7. Title: Johnson's Mexico

    Contributors:

    Summary: Relief shown by hachures. Shows department boundaries, cities, towns, and notable physical features; roads, towns, proposed canals, and proposed railroads across the Isthmus of Tehuantepec on inset. Prime meridians: Greenwich and Washington. Inset: Territory and Isthmus of Tehuantepec. In lower right corner: 56. Probably issued in: Johnson's new illustrated (steel plate) family atlas ... New York : Johnson & Browning, 1862.

    View full record

  8. Title: Johnson's Minnesota and Dakota

    Contributors:

    Summary: Shows county boundaries as of 1858?; From: Johnson's new illustrated family atlas / Johnson & Browning. No. 52.; Relief shown by hachures.; Prime meridians: Greenwich, Washington.; Hand colored. 32 x 41 centimeters Scale approximately 1:2,500,000 General Minnesota Maps

    View full record

  9. Title: Iowa, 1858

    Contributors:

    Summary: 1 map

    View full record

  10. Title: Geological map of Isle Royale, Lake Superior, Michigan

    Contributors:

    Summary: Contours added by Alfred C. Lane, 1908.; Oriented with north toward the upper right.; From: Michigan. Geological Survey. Annual report, 1909. Plate 1. 22 x 91 centimeters Scale approximately 1:100,000 General Map Collection

    View full record

  11. Title: Lower Peninsula

    Contributors:

    Summary: Shows geology and railroads.; Base map: Rand McNally and Company. Rand, McNally & Co.'s new business atlas map of Michigan. c1889.; Appears in: Lane, Alfred Church. The geology of Lower Michigan with reference to borings. 66 x 47 centimeters Scale approximately 1:780,000 General Map Collection

    View full record

  12. Title: Folds: Offshore of Refugio Beach, California, 2012

    Contributors:

    Summary: This line shapefile contains geologic folds for the offshore area of Refugio Beach, California. This map area lies within the Western Transverse Ranges province, north of the southern California Borderland (Fisher and others, 2009). This province has undergone significant north-south compression since the Miocene, and recent global positioning system (GPS) data suggest north-south shortening of about 6 mm/yr (Larson and Webb, 1992). The active west-trending Pitas Point Fault (broad zone including back faults), Red Mountain Fault, and Rincon Creek Fault are some of the structures on which this shortening occurs (e.g., Jackson and Yeats, 1982; Sorlien and others, 2000; Fisher and others, 2009). This fault system, in aggregate, extends for about 100 km through the Ventura and Santa Barbara basins and represents an important earthquake hazard (e.g., Fisher and others, 2009). A map that show these data are published in Scientific Investigations Map 3319, "California State Waters Map Series--Offshore of Refugio Beach, California." This layer is part of USGS Data Series 781. In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP) to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats and geology within the 3-nautical-mile limit of California's State Waters. CSMP has divided coastal California into 110 map blocks, each to be published individually as United States Geological Survey Open-File Reports (OFRs) or Scientific Investigations Maps (SIMs) at a scale of 1:24,000. Maps display seafloor morphology and character, identify potential marine benthic habitats and illustrate both the seafloor geology and shallow (to about 100 m) subsurface geology. Data layers for bathymetry, bathymetric contours, acoustic backscatter, seafloor character, potential benthic habitat and offshore geology were created for each map block, as well as regional-scale data layers for sediment thickness, depth to transition, transgressive contours, isopachs, predicted distributions of benthic macro-invertebrates and visual observations of benthic habitat from video cruises over the entire state. This coverage can be used to to aid in assessments and mitigation of geologic hazards in the coastal region and to provide sufficient geologic information for land-use and land-management decisions both onshore and offshore. These data are intended for science researchers, students, policy makers, and the general public. This information is not intended for navigational purposes.The data can be used with geographic information systems (GIS) software to display geologic and oceanographic information. Conrad, J.E., Ritchie, A.C., Johnson, S.Y. (2015). Folds: Offshore of Refugio Beach, California, 2012. California State Waters Map Series Data Catalog: U.S. Geological Survey Data Series 781. Available at: http://purl.stanford.edu/tp111fr3266. Map political location: Santa Barbara County, California Compilation scale: 1:24,000 Base maps used are hillshades generated from IfSAR, LiDAR, and multibeam mapping both onshore and offshore (see sheet 2, SIM 3319 for more information). References Cited: Fisher, M.A., Sorlien, C.C., and Sliter, R.W., 2009, Potential earthquake faults offshore southern California from the eastern Santa Barbara channel to Dana Point, in Lee, H.J., and Normark, W.R., eds., 2009, Earth science in the urban ocean: The Southern California Continental Borderland: Geological Society of America Special Paper 454, p. 271-290. Jackson, P.A., and Yeats, R.S., 1982, Sructural evolution of Carpinteria basin, western Tranverse Ranges, California: American Association of Petroleum Geologists Bulletin, v. 66, p. 805-829. Larson, K.M., and Webb, F.H., 1992, Deformation in the Santa Barbara Channel from GPS measurements 1987-1991: Geophysical News Letters, v. 19, p. 1491-1494. Sorlien, C.C., Gratier, J.P., Luyendyk, B.P., Hornafius, J.S., and Hopps, T.E., 2000, Map restoration of folded and faulted late Cenozoic strata across the Oak Ridge fault, onshore and offshore Ventura basin, California: Geological Society of America Bulletin, v. 112, p. 1080-1090. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

    View full record

  13. Title: Contours: Offshore of Refugio Beach, California, 2015

    Contributors:

    Summary: This line shapefile contains bathymetric contours at 10 and 50 meter intervals for the offshore area of Refugio Beach, California. A map that show these data are published in Scientific Investigations Map 3319, "California State Waters Map Series--Offshore of Refugio Beach, California." This layer is part of USGS Data Series 781. In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP) to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats and geology within the 3-nautical-mile limit of California's State Waters. CSMP has divided coastal California into 110 map blocks, each to be published individually as United States Geological Survey Open-File Reports (OFRs) or Scientific Investigations Maps (SIMs) at a scale of 1:24,000. Maps display seafloor morphology and character, identify potential marine benthic habitats and illustrate both the seafloor geology and shallow (to about 100 m) subsurface geology. Data layers for bathymetry, bathymetric contours, acoustic backscatter, seafloor character, potential benthic habitat and offshore geology were created for each map block, as well as regional-scale data layers for sediment thickness, depth to transition, transgressive contours, isopachs, predicted distributions of benthic macro-invertebrates and visual observations of benthic habitat from video cruises over the entire state. This coverage can be used to to aid in assessments and mitigation of geologic hazards in the coastal region and to provide sufficient geologic information for land-use and land-management decisions both onshore and offshore. These data are intended for science researchers, students, policy makers, and the general public. This information is not intended for navigational purposes.The data can be used with geographic information systems (GIS) software to display geologic and oceanographic information. Ritchie, A.C., Dartnell, P., Kvitek, R.G., Johnson, S.Y. (2015). Contours: Offshore of Refugio Beach, California, 2015. California State Waters Map Series Data Catalog: U.S. Geological Survey Data Series 781. Available at: http://purl.stanford.edu/cj457gj7638. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

    View full record

  14. Title: Folds: Offshore of Tomales Point, California, 2010

    Contributors:

    Summary: This line shapefile depicts geologic folds within the offshore area of Tomales Point, California. The Point Reyes Peninsula is bounded to the south and west in the offshore by the north- and east-dipping Point Reyes Thrust Fault (McCulloch, 1987; Heck and others, 1990), which lies about 20 km west of Tomales Point. Granitic basement rocks are offset about 1.4 km on this thrust fault offshore of Point Reyes (McCulloch, 1987), and this uplift combined with west-side-up offset on the San Andreas Fault (Grove and Niemi, 2005) resulted in uplift of the Point Reyes Peninsula, including Tomales Point and the adjacent continental shelf. Grove and others (2010) reported uplift rates of as much as 1 mm/yr for the south flank of the Point Reyes Peninsula based on marine terraces, but reported no datable terrace surfaces that could constrain uplift for the flight of 4-5 terraces exposed farther north along Tomales Point. Folds were primarily mapped by interpretation of seismic reflection profile data (see field activity S-15-10-NC). The seismic reflection profiles were collected between 2007 and 2010. A map that shows these data is published in Open-File Report 2015-1088, "California State Waters Map Series--Offshore of Tomales Point, California." This layer is part of USGS Data Series 781. In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP) to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats and geology within the 3-nautical-mile limit of California's State Waters. CSMP has divided coastal California into 110 map blocks, each to be published individually as United States Geological Survey Open-File Reports (OFRs) or Scientific Investigations Maps (SIMs) at a scale of 1:24,000. Maps display seafloor morphology and character, identify potential marine benthic habitats and illustrate both the seafloor geology and shallow (to about 100 m) subsurface geology. Data layers for bathymetry, bathymetric contours, acoustic backscatter, seafloor character, potential benthic habitat and offshore geology were created for each map block, as well as regional-scale data layers for sediment thickness, depth to transition, transgressive contours, isopachs, predicted distributions of benthic macro-invertebrates and visual observations of benthic habitat from video cruises over the entire state. This coverage can be used to to aid in assessments and mitigation of geologic hazards in the coastal region and to provide sufficient geologic information for land-use and land-management decisions both onshore and offshore. These data are intended for science researchers, students, policy makers, and the general public. This information is not intended for navigational purposes.The data can be used with geographic information systems (GIS) software to display geologic and oceanographic information. Hartwell, S.R., Johnson, S.Y., and Manson, M.W. (2014). Folds: Offshore of Tomales Point, California, 2010. California State Waters Map Series Data Catalog: U.S. Geological Survey Data Series 781. Available at: http://purl.stanford.edu/jf036dx3445. Map political location: San Mateo County, California Compilation scale: 1:24,000 Base maps used are hillshades generated from IfSAR, LiDAR, and multibeam mapping both onshore and offshore (see Bathymetry Hillshade--Offshore of Tomales Point, California, DS 781, for more information). . References Cited Grove, K., and Niemi, T.M., 2005, Late Quaternary deformation and slip rates in the northern San Andreas fault zone at Olema Valley, Marin County, California: Tectonophysics, v. 401, p. 231-250. Grove, K, Sklar, L.S., Scherer, A.M., Lee, G., and Davis, J., 2010, Accelerating and spatially-varying crustal uplift and its geomorphic expression, San Andreas fault zone north of San Francisco, California: Tectonophysics, v. 495, p. 256-268. Heck, R.G., Edwards, E.B., Kronen, J.D., Jr., and Willingham, C.R., 1990, Petroleum potential of the offshore outer Santa Cruz and Bodega basins, California, in Garrison, R.E., Greene, H.G., Hicks, K.R., Weber, G.E., and Wright, T.L., eds. Geology and tectonics of the central California coastal region, San Francisco to Monterey: Pacific Section, American Association of Petroleum Geologists Bulletin GB67, p. 143-164. McCulloch, D.S., 1987, Regional geology and hydrocarbon potential of offshore central California, in Scholl, D.W., Grantz, A., and Vedder, J.G., eds., Geology and Resource Potential of the Continental Margin of Western North America and Adjacent Oceans Beaufort Sea to Baja California: Houston, Texas, Circum-Pacific Council for Energy and Mineral Resources, Earth Science Series, v. 6., p. 353-401. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

    View full record

  15. Title: Faults: Offshore of Refugio Beach, California, 2012

    Contributors:

    Summary: This line shapefile contains fault lines within the offshore area of Refugio Beach, California. This map area lies within the Western Transverse Ranges province, north of the southern California Borderland (Fisher and others, 2009). This province has undergone significant north-south compression since the Miocene, and recent global positioning system (GPS) data suggest north-south shortening of about 6 mm/yr (Larson and Webb, 1992). The active west-trending Pitas Point Fault (broad zone including back faults), Red Mountain Fault, and Rincon Creek Fault are some of the structures on which this shortening occurs (e.g., Jackson and Yeats, 1982; Sorlien and others, 2000; Fisher and others, 2009). This fault system, in aggregate, extends for about 100 km through the Ventura and Santa Barbara basins and represents an important earthquake hazard (e.g., Fisher and others, 2009). A map that show these data are published in Scientific Investigations Map 3319, "California State Waters Map Series--Offshore of Refugio Beach, California." This layer is part of USGS Data Series 781. In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP) to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats and geology within the 3-nautical-mile limit of California's State Waters. CSMP has divided coastal California into 110 map blocks, each to be published individually as United States Geological Survey Open-File Reports (OFRs) or Scientific Investigations Maps (SIMs) at a scale of 1:24,000. Maps display seafloor morphology and character, identify potential marine benthic habitats and illustrate both the seafloor geology and shallow (to about 100 m) subsurface geology. Data layers for bathymetry, bathymetric contours, acoustic backscatter, seafloor character, potential benthic habitat and offshore geology were created for each map block, as well as regional-scale data layers for sediment thickness, depth to transition, transgressive contours, isopachs, predicted distributions of benthic macro-invertebrates and visual observations of benthic habitat from video cruises over the entire state. This coverage can be used to to aid in assessments and mitigation of geologic hazards in the coastal region and to provide sufficient geologic information for land-use and land-management decisions both onshore and offshore. These data are intended for science researchers, students, policy makers, and the general public. This information is not intended for navigational purposes.The data can be used with geographic information systems (GIS) software to display geologic and oceanographic information. Conrad, J.E., Ritchie, A.C., Johnson, S.Y. (2015). Faults: Offshore of Refugio Beach, California, 2012. California State Waters Map Series Data Catalog: U.S. Geological Survey Data Series 781. Available at: http://purl.stanford.edu/yg931nr6687. Map political location: Santa Barbara County, California Compilation scale: 1:24,000 Base maps used are hillshades generated from IfSAR, LiDAR, and multibeam mapping both onshore and offshore (see sheet 2, SIM 3319, for more information). References Cited: Fisher, M.A., Sorlien, C.C., and Sliter, R.W., 2009, Potential earthquake faults offshore southern California from the eastern Santa Barbara channel to Dana Point, in Lee, H.J., and Normark, W.R., eds., 2009, Earth science in the urban ocean: The Southern California Continental Borderland: Geological Society of America Special Paper 454, p. 271-290. Jackson, P.A., and Yeats, R.S., 1982, Sructural evolution of Carpinteria basin, western Tranverse Ranges, California: American Association of Petroleum Geologists Bulletin, v. 66, p. 805-829. Larson, K.M., and Webb, F.H., 1992, Deformation in the Santa Barbara Channel from GPS measurements 1987-1991: Geophysical News Letters, v. 19, p. 1491-1494. Sorlien, C.C., Gratier, J.P., Luyendyk, B.P., Hornafius, J.S., and Hopps, T.E., 2000, Map restoration of folded and faulted late Cenozoic strata across the Oak Ridge fault, onshore and offshore Ventura basin, California: Geological Society of America Bulletin, v. 112, p. 1080-1090. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

    View full record

  16. Title: Geology: Offshore of Refugio Beach, California, 2012

    Contributors:

    Summary: This polygon shapefile contains geological features for the offshore area of Refugio Beach, California. The offshore Refugio Beach map area largely consists of a gently offshore-dipping (<1 degree) shelf (10 to ~ 90 m) underlain by sediments derived primarily from relatively small coastal watersheds draining the Santa Ynez Mountains. Nearshore and shelf deposits are primarily sand (Qms) at depths less than about 45 m and more fine-grained sediment - very fine sand, silt and clay (Qmsf), at depths greater than about 45 m. The boundary between Qms and Qmsf is based on observations and extrapolation from sediment sampling (for example, Reid and others, 2006) and camera groundtruthing. The Qms-Qmsf boundary is transitional and approximate, expected to shift based on seasonal to annual to decadal scale cycles in wave climate, sediment supply, and sediment transport. Fine-grained deposits similar to Qmsf also occur below the shelfbreak on the upper slope at water depths greater than 90 m, where they are broken out as a separate unit (Qmsl) based on their location and geomorphology. More coarse-grained deposits recognized on the basis of high backscatter and in some cases moderate seafloor relief have two modes of occurrence. In the relative nearshore (10 to 30 m water depth), coarse-grained strata (Qmsc) underlie laterally coalescing and discontinuous bars at the mouths of steep coastal watersheds. Coarser-grained sediments also form several distinct lobes (Qmscl) in water depths of 25 to 70 m, about 600 to 3,000 m offshore. The lobes range in size from ~100,000 m2 to ~1.5 km2 and are mapped on the basis of high backscatter and subtle positive seafloor relief. These coarse-grained strata were clearly derived from fluvial point sources in the adjacent, steep Santa Ynez Mountains. Bedrock exposures in the nearshore west of El Capitan are assigned to the Miocene Monterey Formation based on proximity to coastal outcrops mapped by Dibblee (1981a, b). Much of the outer shelf (water depths greater than 70 m) is also underlain by undifferentiated Tertiary bedrock (Tbu). Based on the regional cross sections constrained by deep seismic-reflection data and borehole logs (Heck, 1998; Tennyson and Kropp, 1998; Forman and Redin, 2005; Redin, 2005) and high-resolution seismic-reflection data coupled with proprietary oil industry dartcore data (Ashley, 1977), these outer-shelf outcrops consist of the Miocene Sisquoc Formation and the Pliocene Repetto and Pico Formations. These rocks have been uplifted in a large, warped, regional south-dipping homocline that formed above the blind, north-dipping North Channel fault. The fault tip is inferred at about 1.5 sec TWT (~2 km) about 6 to 7 km offshore, beneath the slope and just outside California's State Waters. Bedrock that underlies some parts of the shelf is overlain by a thin (< 1 m?) sediment veneer, recognized based on high backscatter, flat relief, continuity with moderate to high relief bedrock outcrops, and (in some cases) high-resolution, seismic-reflection data (Qms/Qtbu. Qms/Tbu, Qms/Tm). These sediment layers are likely ephemeral - they may or may not be present based on storms, seasonal/annual patterns of sediment movement, or longer-term climate cycles. This area has a long history of petroleum production (Barnum, 1998), and grouped to solitary pockmarks (Qmp) caused by gas seeps are common features in the offshore Refugio map area. Shell discovered the Molino gas field in 1962, 4 km offshore in the southwest part of the map area. Production, by onshore directional drilling of an anticlinal trap, has been underway since the 1960's (Galloway, 1998). A map that show these data are published in Scientific Investigations Map 3319, "California State Waters Map Series--Offshore of Refugio Beach, California." This layer is part of USGS Data Series 781. In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP) to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats and geology within the 3-nautical-mile limit of California's State Waters. CSMP has divided coastal California into 110 map blocks, each to be published individually as United States Geological Survey Open-File Reports (OFRs) or Scientific Investigations Maps (SIMs) at a scale of 1:24,000. Maps display seafloor morphology and character, identify potential marine benthic habitats and illustrate both the seafloor geology and shallow (to about 100 m) subsurface geology. Data layers for bathymetry, bathymetric contours, acoustic backscatter, seafloor character, potential benthic habitat and offshore geology were created for each map block, as well as regional-scale data layers for sediment thickness, depth to transition, transgressive contours, isopachs, predicted distributions of benthic macro-invertebrates and visual observations of benthic habitat from video cruises over the entire state. This coverage can be used to to aid in assessments and mitigation of geologic hazards in the coastal region and to provide sufficient geologic information for land-use and land-management decisions both onshore and offshore. These data are intended for science researchers, students, policy makers, and the general public. This information is not intended for navigational purposes.The data can be used with geographic information systems (GIS) software to display geologic and oceanographic information. Conrad, J.E., Ritchie, A.C., Johnson, S.Y. (2015). Geology: Offshore of Refugio Beach, California, 2012. California State Waters Map Series Data Catalog: U.S. Geological Survey Data Series 781. Available at: http://purl.stanford.edu/pp901rg4093. Map political location: Santa Barbara County, California Compilation scale: 1:24,000 Base maps used are hillshades generated from IfSAR, LiDAR, and multibeam mapping both onshore and offshore (see sheet 2, SIM 3319 for more information). ). References cited: Ashley, R.J., Berry, R.W., and Fischer, P.J., 1977, Offshore geology and sediment distribution of the El Capitan-Gaviota continental shelf, northern Santa Barbara Channel, California: Journal of Sedimentary Petrology, v. 47, no, 1, p. 199-208. Barnum, H.P., 1998, Redevelopment of the western portion of the Rincon offshore oil field, Ventura, California, in Kunitomi, D.S., Hopps, T.E., and Galloway, J.M., eds., Structure and petroleum geology, Santa Barbara Channel, California: American Association of Petroleum Geologists, p. 201â215. Dibblee, T.W., Jr., 1981a, Geologic map of the Tajiquas Quadrangle, California: U.S. Geological Survey Open-File Report 81-371, 1:24,000. Dibblee, T.W., Jr., 1981b, Geologic map of the Gaviota Quadrangle, California: U.S. Geological Survey Open-File Report 81-374, 1:24,000. Dibblee, T.W., Jr., 1981c, Geologic map of the Santa Ynez Quadrangle, California: U.S. Geological Survey Open-File Report 81-371, 1:24,000. Dibblee, T.W., Jr., 1981d, Geologic map of the Solvang Quadrangle, California: U.S. Geological Survey Open-File Report 81-372, 1:24,000. Forman, J., and Redin, T., 2005, Santa Barbara Channel structure and correlation sections, Correlation Section no 37, Arroyo Hondo, Gaviota Quadrangle, Santa Ynez Mts. To North West Santa Rosa Island: American Association of Petroleum Geologists, Pacific Section, Publication CS 37, 1 sheet. Galloway, J.M., 1998, Chronology of petroleum exploration and development in the Santa Barbara channel area, offshore southern California, in Kunitomi, D.S., Hopps, T.E., and Galloway, J.M., eds., Structure and petroleum geology, Santa Barbara Channel, California: American Association of Petroleum Geologists, Pacific Section and Coast Geological Society, Miscellaneous Publication 46, p. 1â12, 1 sheet. Heck, R.G., 1998, Santa Barbara Channel Regional Formline Map, Top Monterey Formation, in Kunitomi, D.S., Hopps, T.E., and Galloway, J.M., 1998, Structure and Petroleum Geology, Santa Barbara Channel, California: American Association of Petroleum Geologists, Pacific Section, Miscellaneous Publication 46, Plate 1. Minor, S.A., Kellogg, K.S., Stanley, R.G., Gurrola, L.D., Keller, E.A., and Brandt, T.R., 2009, Geologic map of the Santa Barbara coastal plain area, Santa Barbara County, California: U.S. Geological Survey Scientific Investigations Map 3001, scale 1:25,000. Redin, T., 2005, Santa Barbara Channel structure and correlation sections, Correlation Section no 36, N-S structure and correlation section, western Santa Ynez Mountains across the Santa Barbara channel to Santa Rosa Island: American Association of Petroleum Geologists, Pacific Section, Publication CS 35, 1 sheet. Reid, J.A., Reid, J.M., Jenkins, C.J., Zimmerman, M., Williams, S.J., and Field, M.E., 2006,usSEABED:Pacific Coast (California Oregon, Washington) offshore surficial-sediment data release: U.S. Geological Survey Data Series 182, http://pubs.usgs.gov/ds/2006/182/. Tennyson, M.E., and Kropp, A.P., 1998, Regional cross section across Santa Barbara channel from northwestern Santa Rosa Island to Canada de Molina, in Kunitomi, D.S., Hopps, T.E., and Galloway, J.M., eds., in Structure and petroleum geology, Santa Barbara Channel, California: American Association of Petroleum Geologists, Pacific Section and Coast Geological Society, Miscellaneous Publication 46, 1 plate. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

    View full record

  17. Title: Geology: Offshore of Tomales Point, California, 2010

    Contributors:

    Summary: This polygon shapefile depicts geologic features within the offshore area of Tomales Point, California. The morphology and the geology of the offshore part of the Offshore of Tomales Point map area result from the interplay between tectonics, sea-level rise, local sedimentary processes, and oceanography. The map area is cut by the northwest-trending San Andreas Fault, the right-lateral transform boundary between the North American and Pacific tectonic plates. The San Andreas strikes through Tomales Bay, the northern part of a linear valley that extends from Bolinas through Olema Valley to Bodega Bay, separating mainland California from the Point Reyes Peninsula. Onshore investigations indicate that this section of the San Andreas Fault has an estimated slip rate of about 17 to 25 mm/yr (Bryant and Lundberg, 2002; Grove and Niemi, 2005). The devastating Great 1906 California earthquake (M 7.8) is thought to have nucleated on the San Andreas Fault about 50 kilometers south of this map area offshore of San Francisco (e.g., Bolt, 1968; Lomax, 2005), with the rupture extending northward through the Offshore of Tomales Point map area to the south flank of Cape Mendocino (Lawson, 1908; Brown and Wolfe, 1972). The Point Reyes Peninsula is bounded to the south and west in the offshore by the north- and east-dipping Point Reyes Thrust Fault (McCulloch, 1987; Heck and others, 1990), which lies about 20 km west of Tomales Point. Granitic basement rocks are offset about 1.4 km on this thrust fault offshore of Point Reyes (McCulloch, 1987), and this uplift combined with west-side-up offset on the San Andreas Fault (Grove and Niemi, 2005) resulted in uplift of the Point Reyes Peninsula, including Tomales Point and the adjacent continental shelf. Grove and others (2010) reported uplift rates of as much as 1 mm/yr for the south flank of the Point Reyes Peninsula based on marine terraces, but reported no datable terrace surfaces that could constrain uplift for the flight of 4-5 terraces exposed farther north along Tomales Point. Because of this Quaternary uplift and relative lack of sediment supply from coastal watersheds, there is extensive rugged, rocky seafloor beneath the continental shelf in the Offshore of Tomales Point map area. Granitic rocks (unit Kg) on the seafloor are mapped on the basis of massive character, roughness, extensive fractures, and high backscatter (see Backscattter A to D--Offshore of Tomales Point, California, DS 781, for more information). Neogene sedimentary rocks (units Tl and Tu) commonly form distinctive "ribs," created by differential seafloor erosion of dipping beds of variable resistance. The more massive offshore outcrops of unit Tu in the southern part of the map area are inferred to represent more uniform lithologies. Slopes on the granitic seafloor (generally 1 to 1.3 degrees) are greater than those over sedimentary rock (generally about 0.5 to 0.6 degrees). Sediment-covered areas occur in gently sloping (less than about 0.6 degrees) mid-shelf environments west and north of Tomales Point, and at the mouth of Tomales Bay. Sediment supply is local, limited to erosion from local coastal bluffs and dunes, small coastal watersheds, and sediment flux out of the mouth of Tomales Bay. Shelf morphology and evolution largely reflects eustacy; sea level has risen about 125 to 130 m over about the last 21,000 years (for example, Lambeck and Chappell, 2001; Peltier and Fairbanks, 2005), leading to broadening of the continental shelf, progressive eastward migration of the shoreline and wave-cut platform, and associated transgressive erosion and deposition. Given present exposure to high wave energy, modern nearshore to mid-shelf sediments are mostly sand (unit Qms) and a mix of sand, gravel, and cobbles (units Qmsc and Qmsd). These sediments are distributed between rocky outcrops at water depths of as much as 65 m (see below). The more coarse-grained sands and gravels (units Qmsc and Qmsd) are primarily recognized on the basis of bathymetry and high backscatter. Unit Qmsd forms erosional lags in scoured depressions that are bounded by relatively sharp contacts with bedrock or sharp to diffuse contacts with units Qms and Qmsc. These scoured depressions are typically a few tens of centimeters deep and range in size from a few 10's of sq m to more than one sq km. Similar unit Qmsd scour depressions are common along this stretch of the California coast (see, for example, Cacchione and others, 1984; Hallenbeck and others, 2012) where surficial offshore sandy sediment is relatively thin (thus unable to fill the depressions) due to both lack of sediment supply and to erosion and transport of sediment during large northwest winter swells. Such features have been referred to as rippled-scour depressions (see, for example, Cacchione and others, 1984) or sorted bedforms (see, for example, Goff and others, 2005; Trembanis and Hume, 2011). Although the general areas in which both unit Qmsd scour depressions and surrounding mobile sand sheets occur are not likely to change substantially, the boundaries of the individual Qmsd depressions are likely ephemeral, changing seasonally and during significant storm events. Unit Qmsf consists primarily of mud and muddy sand and is commonly extensively bioturbated. The location of the inboard contact at water depths of about 65 m is based on meager sediment sampling and photographic data and the inference that if must lie offshore of the outer boundary of coarse-grained units Qmsd and Qmsc. This is notably deeper than the inner contact of unit Qmsf offshore of the nearby Russian River (about 50 m; Klise, 1983) which could may reflect both increased wave energy and significantly decreased supply of muddy sediment. There are two areas of high-backscatter, rough seafloor at water depths of 65 to 70 m west of northern Tomales Point. These areas are notable in that each includes several small (less than about 20,000 sq m), randomly distributed to northwest-trending, irregular "mounds," with as much as 1 m of positive relief above the seafloor (unit Qsr). Seismic-reflection data (see field activity S-15-10-NC) reveal this lumpy material rests on several meters of latest Pleistoce to Holocene sediment and is thus not bedrock outcrop. Rather, it seems likely that this material is marine debris, possibly derived from one (or more) of the more than 60 shipwrecks that have occurred offshore of the Point Reyes Peninsula between 1849 and 1940 (National Park Service, 2012). It is also conceivable that this lumpy terrane consists of biological "hardgrounds" Units Qsw, Qstb, Qdtb, and Qsdtb comprise sediments in Tomales Bay. Anima and others (2008) conducted a high-resolution bathymetric survey of Tomales Bay and noted that strong tidal currents at the mouth of the bay had created a large field of sandwaves, dunes, and flats (unit Qsw). Unit Qkdtb is a small subaqueous sandy delta deposited at the mouth of Keys Creek, the largest coastal watershed draining into this northern part of Tomales Bay. Unit Qstb occurs south of units Qsw and Qdtb, and comprises largely flat seafloor underlain by mixed sand and silt. Unit Qdtb consists of depressions within the sedimentary fill of Tomales Bay. These depressions commonly occur directly offshore of coastal promontories, cover as much as 74,000 sq m, and are as deep as 9 m. Map unit polygons were digitized over underlying 2-meter base layers developed from multibeam bathymetry and backscatter data (see Bathymetry--Offshore of Tomales Point, California and Backscattter A to D--Offshore of Tomales Point, California, DS 781). The bathymetry and backscatter data were collected between 2006 and 2010. A map that shows these data is published in Open-File Report 2015-1088, "California State Waters Map Series--Offshore of Tomales Point, California." This layer is part of USGS Data Series 781. In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP) to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats and geology within the 3-nautical-mile limit of California's State Waters. CSMP has divided coastal California into 110 map blocks, each to be published individually as United States Geological Survey Open-File Reports (OFRs) or Scientific Investigations Maps (SIMs) at a scale of 1:24,000. Maps display seafloor morphology and character, identify potential marine benthic habitats and illustrate both the seafloor geology and shallow (to about 100 m) subsurface geology. Data layers for bathymetry, bathymetric contours, acoustic backscatter, seafloor character, potential benthic habitat and offshore geology were created for each map block, as well as regional-scale data layers for sediment thickness, depth to transition, transgressive contours, isopachs, predicted distributions of benthic macro-invertebrates and visual observations of benthic habitat from video cruises over the entire state. This coverage can be used to to aid in assessments and mitigation of geologic hazards in the coastal region and to provide sufficient geologic information for land-use and land-management decisions both onshore and offshore. These data are intended for science researchers, students, policy makers, and the general public. This information is not intended for navigational purposes.The data can be used with geographic information systems (GIS) software to display geologic and oceanographic information. Hartwell, S.R., Johnson, S.Y., and Manson, M.W. (2014). Geology: Offshore of Tomales Point, California, 2010. California State Waters Map Series Data Catalog: U.S. Geological Survey Data Series 781. Available at: http://purl.stanford.edu/zg934rd8487. Map political location: San Mateo County, California Compilation scale: 1:24,000 Base maps used are hillshades generated from IfSAR, LiDAR, and multibeam mapping both onshore and offshore (see Bathymetry Hillshade--Offshore of Tomales Point, California, DS 781, for more information). References Cited Anima, R. A., Chin, J.L., Finlayson, D.P., McGann, M.L., and Wong, F.L., 2008, Interferometric sidescan bathymetry, sediment and foraminiferal analyses; a new look at Tomales Bay, California: U.S. Geological Survey Open-File Report 2008 - 1237, 33 p. Brown, R.D., Jr., and Wolfe, E.W., 1972, Map showing recently active breaks along the San Andreas Fault between Point Delgada and Bolinas Bay, California: U.S. Geological Survey Miscellaneous Investigations Map I-692, scale 1:24,000. Bryant, W.A., and Lundberg, M.M., compilers, 2002, Fault number 1b, San Andreas fault zone, North Coast section, in Quaternary fault and fold database of the United States: U.S. Geological Survey website, accessed April 4, 2013 at http://earthquakes.usgs.gov/hazards/qfaults. Cacchione, D.A., Drake, D.E., Grant, W.D., and Tate, G.B., 1984, Rippled scour depressions of the inner continental shelf off central California: Journal of Sedimentary Petrology, v. 54, p. 1,280-1,291. Grove, K., and Niemi, T.M., 2005, Late Quaternary deformation and slip rates in the northern San Andreas fault zone at Olema Valley, Marin County, California: Tectonophysics, v. 401, p. 231-250. Grove, K, Sklar, L.S., Scherer, A.M., Lee, G., and Davis, J., 2010, Accelerating and spatially-varying crustal uplift and its geomorphic expression, San Andreas fault zone north of San Francisco, California: Tectonophysics, v. 495, p. 256-268. Klise, D.H., 1984, Modern sedimentation on the California continental margin adjacent to the Russian River: M.S. thesis, San Jose State University, 120 p. Hallenbeck, T.R., Kvitek, R.G., and Lindholm, J., 2012, Rippled scour depressions add ecologically significant heterogeneity to soft-bottom habitats on the continental shelf: Marine Ecology Progress Series, v. 468, p. 119-133. Lambeck, K., and Chappell, J., 2001, Sea level change through the last glacial cycle: Science, v. 292, p. 679-686, doi: 10.1126/science.1059549. Lawson, A.C., ed., 1908, The California earthquake of April 18, 1906, Report of the State Earthquake Investigation Commission: Carnegie Institution of Washington Publication 87, v. 1, 1451 p. and atlas. Lomax, A., 2005, A reanalysis of the hypocentral location and related observations for the Great 1906 California earthquake: Bulletin of the Seismological Society of America, v. 95, p. 861-877. McCulloch, D.S., 1987, Regional geology and hydrocarbon potential of offshore central California, in Scholl, D.W., Grantz, A., and Vedder, J.G., eds., Geology and Resource Potential of the Continental Margin of Western North America and Adjacent Oceans -- Beaufort Sea to Baja California: Houston, Texas, Circum-Pacific Council for Energy and Mineral Resources, Earth Science Series, v. 6., p. 353-401. National Park Service, 2012, Shipwrecks at Point Reyes, accessed May 1, 2013 at: http://www.nps.gov/pore/historyculture/upload/map_shipwrecks.pdf This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

    View full record

  18. Title: Sediment Thickness: Salt Point to Drakes Bay, California, 2009

    Contributors:

    Summary: This layer is a georeferenced raster image containing sediment-thickness data for the areas within the 3-nautical mile limit between Salt Point and Drakes Bay, in California. As part of the USGS's California State Waters Mapping Project, a 50 meter grid of sediment thickness for the seafloor within the 3-nautical mile limit was generated from seismic-reflection data collected in 2009. The resulting grid covers an area of approximately 717 sq km. The volume of sediment accumulated since the Last Glacial Maximum is approximately 6,800 million cubic meters. Contours at 2.5-meter intervals were derived from this grid. This layer is part of USGS Data Series 781. In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP) to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats and geology within the 3-nautical-mile limit of California's State Waters. CSMP has divided coastal California into 110 map blocks, each to be published individually as United States Geological Survey Open-File Reports (OFRs) or Scientific Investigations Maps (SIMs) at a scale of 1:24,000. Maps display seafloor morphology and character, identify potential marine benthic habitats and illustrate both the seafloor geology and shallow (to about 100 m) subsurface geology. Data layers for bathymetry, bathymetric contours, acoustic backscatter, seafloor character, potential benthic habitat and offshore geology were created for each map block, as well as regional-scale data layers for sediment thickness, depth to transition, transgressive contours, isopachs, predicted distributions of benthic macro-invertebrates and visual observations of benthic habitat from video cruises over the entire state. These data are intended for science researchers, students, policy makers, and the general public. This information is not intended for navigational purposes.The data can be used with geographic information systems (GIS) software to display geologic and oceanographic information. Johnson, S.Y., Hartwell, S.R., Watt, J.T., and Sliter, R.W. (2014). Sediment Thickness: Salt Point to Drakes Bay, California, 2009. California State Waters Map Series Data Catalog: U.S. Geological Survey Data Series 781. Available at: http://purl.stanford.edu/nk085bf7278. Sediment thickness and volume within each of the map areas > Salt Point 38.639622 38.479620 -123.482704 -123.278809 > Fort Ross 38.556494 38.396794 -123.305678 -123.102404 > Bodega Bay 38.411542 38.252067 -123.172536 -122.969899 > Tomales Point 38.255180 38.095716 -123.097226 -122.895023 > Point Reyes 38.098263 37.938810 -123.094511 -122.892742 > Drakes Bay 38.038192 37.878737 -122.966411 -122.764735 > > -----sediment thickness-------- > Area Volume > Map block (sq km) Mean (million cu m) > Salt Point 117 12.5 1464 > Fort Ross 100 21.5 2157 > Bodega Bay 128 8.5 1084 > Tomales Point 108 2.1 230 > Point Reyes 175 7.9 1387 > Drakes Bay 89 5.3 476 Additional information about the field activities from which this data set was derived are available online at > http://walrus.wr.usgs.gov/infobank/s/s809nc/html/s-8-09-nc.meta.html Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this Federal Geographic Data Committee-compliant metadata file is intended to document the data set in nonproprietary form, as well as in ArcInfo format, this metadata file may include some ArcInfo-specific terminology. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

    View full record

  19. Title: Faults: Offshore of Fort Ross, California, 2009

    Contributors:

    Summary: This line shapefile contains fault lines for the offshore area of Fort Ross, California. The map was generated from data collected by California State University, Monterey Bay (CSUMB), and by Fugro Pelagos. The map area is cut by the northwest-trending San Andreas Fault, the right-lateral transform boundary between the North American and Pacific tectonic plates. The San Andreas extends across the inner shelf in the southern part of the map, then crosses the shoreline at Fort Ross and continues onland for about 75 km to the east flank of Point Arena (fig. 8-1). Seismic-reflection data are used to map the offshore fault trace, and reveal a relatively simple, 200- to 500-m wide zone typically characterized by one or two primary strands. About 1500 m west of the San Andreas Fault, the mid shelf (between water depths of 40 m and 70 m) in the southernmost part of the map area includes an about 5-km-wide field of elongate, shore-normal sediment lobes (unit Qmsl). Individual lobes within the field are as much as 650-m long and 200-m wide, have as much as 1.5 m (check with Steve) of relief above the surrounding smooth seafloor, and are commonly connected with upslope chutes. Given their morphology and proxmity to the San Andreas fault, we infer that these lobes result from slope failures associated with strong ground motions triggered by large San Andreas earthquakes. Movement on the San Andreas has juxtaposed different coastal bedrock blocks (Blake and others, 2002). Rocks east of the fault that occur along the coast and in the nearshore belong to the late Tertiary, Cretaceous, and Jurassic Franciscan Complex, either sandstone of the Coastal Belt or Central Belt (unit TKfs) or melange of the central terrane (unit fsr). Bedrock west of the fault are considered part of the Gualala Block (Elder, 1998) and include the Eocene and Paleocene German Rancho Formation (unit Tgr) and the Miocene sandstone and mudstone of the Fort Ross area (unit Tsm). This section of the San Andreas Fault onland has an estimated slip rate of about 17 to 25 mm/yr (Bryant and Lundberg, 2002). The devastating Great 1906 California earthquake (M 7.8) is thought to have nucleated on the San Andreas Fault about 100 kilometers south of this map area offshore of San Francisco (e.g., Bolt, 1968; Lomax, 2005), with the rupture extending northward through the Offshore of Fort Ross map area to the south flank of Cape Mendocino. Emergent marine terraces along the coast in the Offshore of Fort Ross map area record recent contractional deformation associated with the San Andreas Fault system. Prentice and Kelson (2006) report uplift rates of 0.3 to 0.6 mm/yr for a late Pleistocene terrace exposed at Fort Ross, and this recent uplift must also have affect the nearshore and inner shelf. Previously, McCulloch (1987) mapped a nearshore (within 3 to 5 km of the coast) fault zone from Point Arena to Fort Ross (Fig. 8-1) using primarily deeper industry seismic-reflection data. Subsequently, Dickinson and others (2005) named this structure the "Gualala Fault." Our mapping, also based on seismic-reflection data, reveals this structure as a steep, northeast trending fault and similarly shows the fault ending to the south in the northern part of the Offshore of Fort Ross map area. We have designated the zone of faulting and folding above this structure the "Gualala Fault deformation zone." Faults were primarily mapped by interpretation of seismic reflection profile data (see field activity S-8-09-NC). The seismic reflection profiles were collected between 2007 and 2010. This layer is part of USGS Data Series 781. In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP) to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats and geology within the 3-nautical-mile limit of California's State Waters. CSMP has divided coastal California into 110 map blocks, each to be published individually as United States Geological Survey Open-File Reports (OFRs) or Scientific Investigations Maps (SIMs) at a scale of 1:24,000. Maps display seafloor morphology and character, identify potential marine benthic habitats and illustrate both the seafloor geology and shallow (to about 100 m) subsurface geology. Data layers for bathymetry, bathymetric contours, acoustic backscatter, seafloor character, potential benthic habitat and offshore geology were created for each map block, as well as regional-scale data layers for sediment thickness, depth to transition, transgressive contours, isopachs, predicted distributions of benthic macro-invertebrates and visual observations of benthic habitat from video cruises over the entire state. These data are intended for science researchers, students, policy makers, and the general public. This information is not intended for navigational purposes.The data can be used with geographic information systems (GIS) software to display geologic and oceanographic information. Additionally, this coverage can provide a geologic map for the public and geoscience community to aid in assessments and mitigation of geologic hazards in the coastal region and sufficient geologic information for land-use and land-management decisions both onshore and offshore. Johnson, S.Y., Hartwell, S.R., and Manson, M.W. (2014). Faults: Offshore of Fort Ross, California, 2009. California State Waters Map Series Data Catalog: U.S. Geological Survey Data Series 781. Available at: http://purl.stanford.edu/nv824nq7744. Map political location: San Mateo County, California Compilation scale: 1:24,000 Base maps used are hillshades generated from IfSAR, LiDAR, and multibeam mapping both onshore and offshore (see Bathymetry--Offshore of Fort Ross Map Area, California). References Cited Blake, M.C., Jr., Graymer, R.W., and Stamski, R.E., 2002, Geologic map and map database of western Sonoma, northernmost Marin, and southernmost Mendocino counties, California: U.S. Geological Survey Miscellaneous Field Studies Map 2402, scale 1:100,000. Bolt, B.A., 1968, The focus of the 1906 California earthquake: Bulletin of the Seismological Society of America, v. 58, p. 457-471. Bryant, W.A., and Lundberg, M.M., compilers, 2002, Fault number 1b, San Andreas fault zone, North Coast section, in Quaternary fault and fold database of the United States: U.S. Geological Survey website, accessed April 4, 2013, at http://earthquakes.usgs.gov/hazards/qfaults. Dickinson, W.R., Ducea, M., Rosenberg, L.I., Greene, H.G., Graham, S.A., Clark, J.C., Weber, G.E., Kidder, S., Ernst, W.G., and Brabb, E.E., 2005, Net dextral slip, Neogene San Gregorio-Hosgri Fault Zone, coastal California: Geologic evidence and tectonic implications: Geological Society of America Special Paper 391, 43 p. Elder, W.P., ed., 1998, Geology and tectonics of the Gualala Block, northern California: Pacific Section, Society of Economic Paleontologists and Mineralogists, Book 84, 222 p. Lomax, A., 2005, A reanalysis of the hypocentral location and related observations for the Great 1906 California earthquake: Bulletin of the Seismological Society of America, v. 95, p. 861-877. McCulloch, D.S., 1987, Regional geology and hydrocarbon potential of offshore central California, in Scholl, D.W., Grantz, A., and Vedder, J.G., eds., Geology and Resource Potential of the Continental Margin of Western North America and Adjacent Oceans -- Beaufort Sea to Baja California: Houston, Texas, Circum-Pacific Council for Energy and Mineral Resources, Earth Science Series, v. 6., p. 353-401. Prentice, C.S., and Kelson, K.I., 2006, The San Andreas fault in Sonoma and Mendocino counties, in Prentice, C.S., Scotchmoor, J.G., Moores, E.M., and Kiland, J.P., eds., 1906 San Francisco Earthquake Centennial Field Guides: Field trips associated with the 100th Anniversary Conference, 18-23 April 2006, San Francisco, California: Geological Society of America Field Guide 7, p. 127-156. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

    View full record

  20. Title: Folds: Offshore of Pacifica, California, 2010

    Contributors:

    Summary: This line shapefile contains geologic folds in the offshore area of Pacifica, California. The Offshore of Pacifica map area straddles the right-lateral transform boundary between the North American and Pacific plates and is cut by several active faults that cumulatively form a distributed shear zone, including the San Andreas Fault, the eastern strand of the San Gregorio Fault, the Golden Gate Fault, and the Potato Patch Fault (sheets 8, 9; Bruns and others, 2002; Ryan and others, 2008). These faults are covered by Holocene sediments (mostly units Qms, Qmsb, Qmst) with no seafloor expression, and are mapped using seismic-reflection data (sheet 8). The San Andreas Fault is the primary plate-boundary structure and extends northwest across the map area; it intersects the shoreline 10 km north of the map area at Pacifica Lagoon, and 3 km south of the map area at Mussel Rock. This section of the San Andreas Fault has an estimated slip rate of 17 to 24 mm/yr (U.S. Geological Survey, 2010), and the devastating Great 1906 California earthquake (M 7.8) is thought to have nucleated on the San Andreas a few kilometers offshore of San Francisco within the map area (sheet 9; Bolt, 1968; Lomax, 2005). The San Andreas Fault forms the boundary between two distinct basement terranes, Upper Jurassic to Lower Cretaceous rocks of the Franciscan Complex to the east, and Late Cretaceous granitic and older metamorphic rocks of the Salinian block to the west. Franciscan Complex rocks (unit KJf, undivided) form seafloor outcrops at and north of Point Lobos adjacent to onland exposures. The Franciscan is divided into 13 different units for the onshore portion of this geologic map based on different lithologies and ages, but the unit cannot be similarly divided in the offshore because of a lack of direct observation and (or) sampling. Folds were primarily mapped by interpretation of seismic reflection profile data (see S-15-10-NC and F-2-07-NC). The seismic reflection profiles were collected between 2007 and 2010. A map which shows these data is published in Scientific Investigations Map 3302, "California State Waters Map Series--Offshore of Coal Oil Point, California." This layer is part of USGS Data Series 781. In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP) to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats and geology within the 3-nautical-mile limit of California's State Waters. CSMP has divided coastal California into 110 map blocks, each to be published individually as United States Geological Survey Open-File Reports (OFRs) or Scientific Investigations Maps (SIMs) at a scale of 1:24,000. Maps display seafloor morphology and character, identify potential marine benthic habitats and illustrate both the seafloor geology and shallow (to about 100 m) subsurface geology. Data layers for bathymetry, bathymetric contours, acoustic backscatter, seafloor character, potential benthic habitat and offshore geology were created for each map block, as well as regional-scale data layers for sediment thickness, depth to transition, transgressive contours, isopachs, predicted distributions of benthic macro-invertebrates and visual observations of benthic habitat from video cruises over the entire state. These data are intended for science researchers, students, policy makers, and the general public. This information is not intended for navigational purposes.The data can be used with geographic information systems (GIS) software to display geologic and oceanographic information. Additionally, this coverage can provide a geologic map for the public and geoscience community to aid in assessments and mitigation of geologic hazards in the coastal region and sufficient geologic information for land-use and land-management decisions both onshore and offshore. Greene, H.G., Hartwell, S.R., Manson, M.W., Johnson, S.Y., Dieter, B.E., Phillips, E.L., and Watt, J.T. (2014). Folds: Offshore of Pacifica, California, 2010. California State Waters Map Series Data Catalog: U.S. Geological Survey Data Series 781. Available at: http://purl.stanford.edu/mh718dy4756. Map political location: San Mateo County, California Compilation scale: 1:24,000 Base maps used are hillshades generated from IfSAR, LiDAR, and multibeam mapping both onshore and offshore (see Bathymetry--Offshore of Pacifica map area, California, DS 781, for more information). References Cited Bolt, B.A., 1968, The focus of the 1906 California earthquake: Bulletin of the Seismological Society of America, v. 58, p. 457-471. Bruns, T.R., Cooper, A.K., Carlson, P.R., and McCulloch, D.S., 2002, Structure of the submerged San Andreas and San Gregorio fault zones in the Gulf of Farallones as inferred from high-resolution seismic-reflection data, in Parsons, T. (ed.), Crustal structure of the coastal and marine San Francisco Bay region, California: U.S. Geological Survey Professional Paper 1658, p. 77-117. Lomax, A., 2005, A reanalysis of the hypocentral location and related observations for the Great 1906 California earthquake: Bulletin of the Seismological Society of America, v. 95, p. 861-877. Ryan, H.F., Parsons, T., and Sliter, R.W., 2008. Vertical tectonic deformation associated with the San Andreas fault zone offshore of San Francisco, California. Tectonophysics, 429 (1-2), p. 209-224. U.S. Geological Survey and California Geological Survey, 2010, Quaternary fault and fold database for the United States, accessed April 5, 2012, from USGS website: http://earthquake.usgs.gov/hazards/qfaults/. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

    View full record

Need help?

Ask GIS