Offshore geology and geomorphology -- Estero Bay map area [sheet 3]

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Title:
Offshore geology and geomorphology -- Estero Bay map area [sheet 3]
Abstract:
This part of SIM 3327 presents data for geologic units on the offshore geologic and geomorphic map of the Estero Bay map area, in the vicinity of Morro Bay, California. The vector data file is included in "Geology_ EsteroBay.zip," which is accessible from <https://pubs.usgs.gov/sim/3327/data/sim3327_data_catalog.html>.
Offshore geologic units were delineated on the basis of integrated analysis of adjacent onshore geology (see “Additional References for Onshore Geologic Mapping” list), seafloor-sediment and rock samples (Reid and others, 2006; Pacific Gas and Electric Company, 2011), multibeam bathymetry and backscatter imagery, magnetic data (Langenheim and others, 2009, 2012; Sliter and others, 2009), and high-resolution seismic-reflection profiles (Sliter and others, 2009). To maintain onshore-to-offshore consistency, map-unit symbols for the Mesozoic and Tertiary units reflect the published onshore-mapping usage. If no onshore-equivalent unit exists, as is the case with the Quaternary units, the map-unit symbols are made up of letters that indicate the following: the Period, usually followed by “m” for marine sediment; the predominant sediment type; and, finally, a geomorphic descriptor, if applicable.
Nearshore and inner shelf deposits are predominantly sand (Qms), as determined by seafloor sampling (Reid and others, 2006). These sandy-shelf areas locally include coarser grained units such as channel deposits (Qmc), rills (Qmr), and sorted bedforms (Qmss, Trembanis and Hume, 2011). Unit Qmss typically exists as erosional lags in scour depressions whose contacts with horizontal sand sheets of unit Qms are usually relatively sharp but, less commonly, are diffuse. These scour depressions, which generally form irregular to lenticular exposures that have abrupt landward contacts with bedrock, typically are a few tens of centimeters deep and range in size from a few tens of meters to more than 1 km2. Such scour depressions are common along this stretch of the California coast (see, for example, Cacchione and others, 1984; Hallenbeck and others, 2012), where offshore sandy sediment is relatively thin (and, thus, is unable to fill the depressions) owing to low sediment supply and also to erosion and transport of sediment during large northwest winter swells.
Inner shelf deposits (predominantly sand) grade to finer grained (mud and sand) outer shelf (Qmsf) and slope (Qmsl) deposits at depths greater than 70 m. The boundary between units Qms and Qmsf was determined on the basis of seafloor-sediment samples (Reid and others, 2006), as well as interpretation of multibeam backscatter imagery. This boundary likely shifts seaward or landward as a result of seasonal- to annual- to decadal-scale cycles in sediment supply, sediment transport, and wave climate. These shelf and slope deposits locally contain pockmarks (Qmp), hummocky relief (Qmsh), and landslide deposits (Qls). Landslide deposits may represent various forms of submarine sediment instabilities, including slumps, slides, and collapse depressions.
Where an older unit (typically bedrock) is overlain by a thin (less than 2 m) Quaternary deposit, a composite geologic unit is mapped; the composite unit, shown with a stipple pattern on the older unit, is designated by a composite label indicating both the overlying sediment cover and the lower (older) unit, separated by a slash (/). For example, Qms/Tus indicates that a thin sheet of Qms overlies Tus. Such units are recognized on the basis of high backscatter, low relief, continuity with moderate- to high-relief bedrock outcrops, and (in most cases) high-resolution seismic-reflection data. The overlying sediment is interpreted as an ephemeral layer that may or may not be continuously present, depending on storms, seasonal and (or) annual patterns of sediment movement, or longer term climate cycles.
Sea level was approximately 120 to 130 m lower during the Last Glacial Maximum (about 21 ka; see, for example, Lambeck and Chappell, 2001; Gornitz, 2009). This approximate depth corresponds to the modern shelf break, a lateral change from the gently dipping (0.8° to 1.0°) outer shelf to the slightly more steeply dipping (about 1.5° to 2.5°) upper slope in the central and northern parts of the map area. South of Point San Luis in San Luis Bay (sheets 5, 6), deltaic deposits offshore of the mouth of the Santa Maria River (11 km south of the map area) have prograded across the shelf break and now form a continuous low-angle (about 0.8°) ramp that extends to water depths of more than 160 m. The shelf break defines the landward boundary of slope deposits (Qmsl). North of Estero Bay, the shelf break is characterized by a distinctly sharp slope break that is mapped as a landslide headscarp above landslide deposits (Qls) (sheets 1, 2). Multibeam imagery and seismic-reflection profiles across this part of the shelf break show evidence of slope failure, such as slumping, sliding, and soft-sediment deformation, along the entire length of the scarp. Notably, this shelf-break scarp corresponds to a west splay of the Hosgri Fault that dies out just north of the scarp, suggesting that faulting is controlling the location (and instability) of the shelf break in this area.
Lithologies of Tertiary and older seafloor bedrock units were determined on the basis of seafloor samples where available; otherwise, they were interpreted on the basis of their correlation to onshore geology, using their seafloor texture visible in multibeam imagery in addition to their magnetic character. Tertiary units mapped in the offshore include rocks of the Obispo, Monterey, and Pismo Formations. The rhythmically bedded Monterey and Pismo Formations are characterized by their distinctive seafloor texture in multibeam imagery; in addition, they are relatively nonmagnetic. These rocks are underlain by, or are in fault contact with, Jurassic and Cretaceous basement that consists of rocks of either the two unnamed sandstone units (Ksl, Kslc), an unnamed graywacke unit (KJug), the Franciscan Complex (KJf), or the Coast Range ophiolite (Jo). These older units often are characterized by irregular, lumpy seafloor texture and complex magnetic signatures, owing to the highly deformed nature of the variably magnetic rocks.
Certain Mesozoic and Tertiary basement rocks, including ultramafic rocks of the Coast Range ophiolite (Jo) and diabase and basalts of the Obispo Formation (Tod), are highly magnetic, making high-resolution magnetic data (fig. 3 on sheets 2, 4, 6) an important mapping tool. Although metavolcanic rocks within the Franciscan Complex in this map area apparently are not magnetic, serpentinite is. Serpentinite, which is derived from the Coast Range ophiolite and is associated with the Franciscan Complex, commonly forms elongate magnetic bodies along fault zones and, thus, can assist in fault mapping.
This map area, which encompasses part of the Los Osos structural domain, lies on the east flank of the offshore Santa Maria Basin (McCulloch, 1987; Lettis and others, 2004), within the broader Pacific–North American plate transform margin. The Los Osos domain is characterized by a series of onshore, northwest-trending, fault-bounded basins and ranges that extend offshore, where they are partly covered by marine sediment and are truncated by the northwest-striking, right-lateral Hosgri Fault. The Hosgri Fault is an approximately 170-km-long (or longer?) right-lateral strike-slip fault (Petersen and others, 2008) that has an inferred Quaternary slip rate of 1 to 3 mm/yr (Hanson and Lettis, 1994; Hanson and others, 2004).
The shallow (upper 200 m) structure of the Hosgri Fault, as revealed in high-resolution seismic-reflection data, is a vertical fault zone that offsets the seafloor in numerous locations and that has many bends in strike that result in localized areas of uplift and subsidence. The map on sheet 1 shows the Hosgri Fault as being continuous with the onshore San Simeon Fault, and interpretation of high-resolution seismic-reflection data (tracklines shown in fig. 2 on sheet 2) provides compelling evidence that this is the case (Johnson and Watt, 2012). This interpretation contrasts with previous interpretations (Pacific Gas and Electric Company, 1988; Lettis and others, 1990; Hanson and others, 2004) that showed the Hosgri Fault as ending just north of Point Estero, with slip transferring to the San Simeon Fault through a releasing right step. Note that previous interpretations considered the stepover and associated pull-apart basin to be a barrier to earthquake rupture, and so our detailed mapping indicating that no Hosgri–to–San Simeon stepover exists has important implications for earthquake hazards (for a more detailed discussion, see Johnson and Watt, 2012).
Both the Los Osos and Shoreline Faults, which converge with the Hosgri Fault within the map area, are part of a broader fault system within the central Coast Ranges. The Los Osos Fault, as imaged with multibeam and high-resolution seismic-reflection data, forms a west-northwest-striking zone (1 to 3 km wide) of near-vertical faulting. Three distinct strands (north, central, and south) are evident on shallow seismic-reflection profiles. The Shoreline Fault, first recognized as a northwest-striking, vertical zone of earthquake hypocenters that parallels the coastline (Hardebeck, 2010), is expressed on the seafloor as a series of discontinuous, en echelon lineations and scarps visible in multibeam imagery. Detailed marine and airborne (helicopter) magnetic data also reveal a linear trend of magnetic anomalies, the edges of which are coincident with (or parallel to) the surface expression of the Shoreline Fault.
Reference cited:
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. 1280-1291.
Gornitz, V., 2009, Sea level change, post-glacial, in Gornitz, V., ed., Encyclopedia of paleoclimatology and ancient environments: Springer, Encyclopedia of Earth Sciences Series, p. 887–893.
Hanson, K.L., Lettis, W.R., 1994, Estimated Pleistocene slip rate for the San Simeon fault zone, south-central coastal California, in Seismotectonics of the Central California Coast Ranges, Alterman, I.B., McMullen, R.B., Cluff, L.S., and Slemmons, D.B. (Eds.): Geological Society of America Special Paper 292, p. 133-150.
Hanson, K.L., Lettis, W.R., McLaren, M.K., Savage, W.U., and Hall, N.T., 2004, Style and rate of quaternary deformation of the Hosgri fault zone, offshore south-central California, in Evolution of sedimentary basins/offshore oil and gas investigations- Santa Maria Province, Keller, M.A. (Ed.): U.S. Geological Survey Bulletin 1995-BB, 37 p.
Hardebeck, J.L., 2010, Seismotectonics and fault structure of the California Central Coast: Bulletin of the Seismological Society of America, v. 100, p. 1031-1050.
Johnson, S.Y., and Watt, J.T., 2012, Influence of fault trend, bends, and convergence on shallow structure and geomorphology of the Hosgri strike-slip fault, offshore central California: Geosphere, v. 8, no. 6, 25 p.
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.
Langenheim, V.E., R.C. Jachens, and K. Moussaoui (2009). Aeromagnetic survey map of the central California Coast Ranges, USGS Open File Rept. 2009-1044, <https://pubs.usgs.gov/of/2009/1044/>.
Lettis, W.R., Hanson, K.L., Unruh, J.R., McLaren, M., and Savage, W.U., 2004, Quaternary tectonic setting of South-Central Coastal California: in, Evolution of sedimentary basins/offshore oil and gas investigations-Santa Maria Province, Keller, M.A. (Ed.): U.S. Geological Survey Bulletin 1995-AA, 24 p.
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.
Pacific Gas and Electric Company, 2011, Report on the analysis of the Shoreline Fault Zone, central coastal California, Report to the U.S. Nuclear Regulatory Commission, <http://www.pge.com/myhome/edusafety/systemworks/dcpp/shorelinereport/>.
Petersen, M.D., Frankel, A.D., Harmsen, S.C., Mueller, C.S., Haller, K.M., Wheeler, R.L., Wesson, R.L., Zeng, ., Boyd, O.S., Perkins, D.M., Luco, N., Field, E.H., Wills, C.J., and Rukstales, K.S., 2008, Documentation for the 2008 update of the United States National Seismic Hazard Maps: U.S. Geological Survey Open-File Report 2008-1128, 61 p.
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, <https://pubs.usgs.gov/ds/2006/182/>.
Sliter, R.W., Triezenberg, P.J., Hart, P.E., Watt, J.T., Johnson, S.Y., and Scheirer, D.S., 2009, High resolution seismic-reflection and marine magnetic data along the Hosgri fault zone, central California: U.S. Geological Survey 2009-1100, v. 1.1, <https://pubs.usgs.gov/of/2009/1100/>.
Trembanis, A.C., and Hume, T.M., 2011, Sorted bedforms on the inner shelf off northeastern New Zealand—Spatiotemporal relationships and potential paleo-environmental implications: Geo-Marine Letters, v. 31, p. 203–214.
Supplemental_Information:
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.
  1. How should this data set be cited?

    Watt, Janet T., 2015, Offshore geology and geomorphology -- Estero Bay map area [sheet 3]:.

    This is part of the following larger work.

    Watt, Janet T., Johnson, Samuel Y., Hartwell, Stephen R., and Roberts, Michelle, 2015, Offshore Geology and Geomorphology from Point Piedras Blancas to Pismo Beach, San Luis Obispo and Santa Barbara Counties, California: Scientific Investigations Map SIM 3327, U.S. Geological Survey, Reston, VA.

    Online Links:

  2. What geographic area does the data set cover?

    West_Bounding_Coordinate: -121.180799
    East_Bounding_Coordinate: -120.795739
    North_Bounding_Coordinate: 35.496323
    South_Bounding_Coordinate: 35.277811

  3. What does it look like?

  4. Does the data set describe conditions during a particular time period?

    Calendar_Date: 2015
    Currentness_Reference: Publication Date

  5. What is the general form of this data set?

    Geospatial_Data_Presentation_Form: vector digital data

  6. How does the data set represent geographic features?

    1. How are geographic features stored in the data set?

      This is a Vector data set. It contains the following vector data types (SDTS terminology):

      • GT-polygon composed of chains (516)

    2. What coordinate system is used to represent geographic features?

      The map projection used is WGS 1984 UTM Zone 10N.

      Projection parameters:
      Scale_Factor_at_Central_Meridian: 0.9996
      Longitude_of_Central_Meridian: -123.0
      Latitude_of_Projection_Origin: 0.0
      False_Easting: 500000.0
      False_Northing: 0.0

      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 0.000100
      Ordinates (y-coordinates) are specified to the nearest 0.000100
      Planar coordinates are specified in Meter

      The horizontal datum used is D WGS 1984.
      The ellipsoid used is WGS 1984.
      The semi-major axis of the ellipsoid used is 6378137.0.
      The flattening of the ellipsoid used is 1/298.257224.

  7. How does the data set describe geographic features?

    Geology
    Polygons representing geologic / geomorphic map units (Source: This report)

    FID
    Internal feature number. (Source: ESRI)

    Sequential unique whole numbers that are automatically generated.

    Shape
    Feature geometry. (Source: ESRI)

    Coordinates defining the features.

    MapUnitAbb
    Map Unit abbreviation (Source: This report)

    ValueDefinition
    afArtificial fill
    Jo?Coast Range ophiolite (uncertain)
    KJfFranciscan Complex
    KsiUnnamed sandstone and interbedded shale
    TKuBedrock, undivided
    QlsLandslide deposits
    QmcMarine channel deposits
    Qmp?Marine pockmarks (uncertain)
    QmsMarine nearshore and shelf deposits
    Qms/Jo?Thin (0-4 m) ephemeral layer of marine sediment overlying Coast Range ophiolite (uncertain)
    Qms/KJfThin (0-4 m) ephemeral layer of marine sediment overlying Franciscan Complex
    Qms/KsiThin (0-4 m) ephemeral layer of marine sediment overlying unnamed sandstone and interbedded shale
    Qms/TKuThin (0-4 m) ephemeral layer of marine sediment overlying bedrock, undivided
    Qms/TmpmThin (0-4 m) ephemeral layer of marine sediment overlying Pismo Foramtion, Miguelito Member
    Qms/TusThin (0-4 m) ephemeral layer of marine sediment overlying sedimentary bedrock
    QmscCoarse-grained marine nearshore and shelf deposits
    QmsfFine-grained marine nearshore and shelf deposits
    QmshMarine shelf hummocky deposits
    QmslMarine slope deposits
    QmssMarine shelf sorted bedforms
    TKuBedrock, undivided
    TmpmPismo Formation, Miguelito Member
    TusSedimentary bedrock

    UnitType
    short description of map unit (See Map Unit Abbreviation Definitions) (Source: This report)

    text description of map unit

    Shape_Area
    Area of feature in internal units squared. (Source: ESRI)

    Positive real numbers that are automatically generated.


Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)

  2. Who also contributed to the data set?

  3. To whom should users address questions about the data?

    USGS Pacific Coastal & Marine Science Center
    Attn: Janet Watt
    Geologist
    400 Natural Bridges Drive
    Santa Cruz, CA 95060
    USA

    (831) 460-7565 (voice)
    (831) 427-4748 (FAX)
    jwatt@usgs.gov


Why was the data set created?

These data are intended for science researchers, students, policy makers, and the general public. These data can be used with geographic information systems or other software to aid in assessments and mitigation of geologic hazards in the central California coastal region and to provide sufficient geologic information for land-use and land-management decisions both onshore and offshore.


How was the data set created?

  1. From what previous works were the data drawn?

    CSUMB (2010) (source 1 of 8)
    Seafloor Mapping Lab, California State University Monterey Bay, 20101231, scc08_2mbathy.

    Online Links:

    Type_of_Source_Media: digital file of gridded elevation data (ArcInfo GRID)
    Source_Contribution: Digital Elevation Model (2 meter resolution)

    CSUMB (2010) (source 2 of 8)
    Seafloor Mapping Lab, California State University Monterey Bay, 20101231, scc09_2mbathy.

    Online Links:

    Type_of_Source_Media: digital file of gridded elevation data (ArcInfo GRID)
    Source_Contribution: Digital Elevation Model (2 meter resolution)

    CSUMB (2010) (source 3 of 8)
    Seafloor Mapping Lab, California State University Monterey Bay, 20101231, scc10_2mbathy.

    Online Links:

    Type_of_Source_Media: digital file of gridded elevation data (ArcInfo GRID)
    Source_Contribution: Digital Elevation Model (2 meter resolution)

    CSUMB (2011) (source 4 of 8)
    Seafloor Mapping Lab, California State University Monterey Bay, 2011, scc11_2mbathy.

    Online Links:

    Type_of_Source_Media: digital file of gridded elevation data (ArcInfo GRID)
    Source_Contribution: Digital Elevation Model (2 meter resolution)

    CSUMB (2011) (source 5 of 8)
    Seafloor Mapping Lab, California State University Monterey Bay, 2011, scc12_2mbathy.

    Online Links:

    Type_of_Source_Media: digital file of gridded elevation data (ArcInfo GRID)
    Source_Contribution: Digital Elevation Model (2 meter resolution)

    CSUMB (2010) (source 6 of 8)
    Seafloor Mapping Lab, California State University Monterey Bay, 20101231, scc13_2mbathy.

    Online Links:

    Type_of_Source_Media: digital file of gridded elevation data (ArcInfo GRID)
    Source_Contribution: Digital Elevation Model (2 meter resolution)

    CSUMB (2011) (source 7 of 8)
    Seafloor Mapping Lab, California State University Monterey Bay, 2011, scc14_2mbathy.

    Online Links:

    Type_of_Source_Media: digital file of gridded elevation data (ArcInfo GRID)
    Source_Contribution: Digital Elevation Model (2 meter resolution)

    Sliter and others, 2009 (source 8 of 8)
    Sliter, Ray W., Triezenberg, Peter J., Hart, Patrick E., Watt, Janet T., Johnson, Samuel Y., and Scheirer, Daniel S.,, 2009, High-Resolution Seismic-Reflection and Marine Magnetic Data Along the Hosgri Fault Zone, Central California: U.S. Geological Survey Open-File Report 2009-1100, U.S. Geological Survey, Menlo Park, CA.

    Online Links:

    Type_of_Source_Media:
    seismic data files (.sgy files) ASCII lat/long shotpoint files TIFF images of processed seismic lines
    Source_Contribution:
    Digital seismic data used to interpret subsurface geologic structure

  2. How were the data generated, processed, and modified?

    Date: 2009 (process 1 of 1)
    Map Unit polygons were digitized over underlying 2-meter base layers developed from multibeam bathymetry and backscatter data. Derivatives such as slope and curvature were generated from source rasters. Interpreted rasters include amplitude, hillshaded bathymetry (using various illumination angles and vertical exaggeration), slope, and curvature. Curvature was decomposed into profile and plan curvature for analysis purposes.

  3. What similar or related data should the user be aware of?


How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?

  2. How accurate are the geographic locations?

    Polygons were primarily mapped by one of the following methods: (1) interpretation of 2-meter resolution hillshaded bathymetry data from bathymetric lidar and sonar surveys (see CSUMB 2010); (2) interpretation of 2-meter resolution amplitude (backscatter) data from bathymetric sonar surveys (see CSUMB 2010); (3) interpretation of 2-meter slope and curvature derivatives of bathymetry data and (4) interpretation of seismic reflection profile data.
    Map Unit contact locations were interpreted typically at a scale of between 1:1,000 and 1:2,000 using the above base data. Bathymetric sonar and LiDAR data have a horizontal accuracy greater than the resolution of the base data, while seismic reflection data have a layback component, as well as error introduced by resolution and angle of intersection of mapped features. Consequently, the horizontal accuracy of mapped faults and folds is probably about 10 to 20 meters.
    Most digitized positions on the map are estimated to have better than 5 m horizontal accuracy. There is no elevation data in the database.

  3. How accurate are the heights or depths?

  4. Where are the gaps in the data? What is missing?

    Data are complete: no offshore features that could be accurately identified and represented at the compilation scale of 1:24,000 were eliminated or generalized. The smallest area represented is approximately 100 square meters. All geospatial database elements are attributed.

  5. How consistent are the relationships among the observations, including topology?

    Map elements were visually checked for overshoots, undershoots, duplicate features, polygon closure, and other errors by the lead authors and by the GIS technician(s) who created the digital database. Review drafts of the map were reviewed internally by at least two other geologists for consistency with basic geologic principles and general conformity to USGS mapping standards.


How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Access_Constraints:
If physical samples or materials are available, constraints on their on-site access are described in "WR CMG Sample Distribution Policy" at URL: <http://walrus.wr.usgs.gov/infobank/programs/html/main/sample-dist-policy.html>
Use_Constraints:
This information is not intended for navigational purposes.
Read and fully comprehend the metadata prior to data use. Uses of these data should not violate the spatial resolution of the data. Where these data are used in combination with other data of different resolution, the resolution of the combined output will be limited by the lowest resolution of all the data.
Acknowledge the U.S. Geological Survey in products derived from these data. Share data products developed using these data with the U.S. Geological Survey.
This 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.
Although this Federal Geographic Data Committee-compliant metadata file is intended to document these data in nonproprietary form, as well as in ArcInfo format, this metadata file may include some ArcInfo-specific terminology.

  1. Who distributes the data set? (Distributor 1 of 1)

    U.S. Geological Survey, Coastal and Marine Geology Program
    Attn: Janet Watt
    400 Natural Bridges Drive
    Santa Cruz, CA 95060-5792
    US

    831-460-7565 (voice)
    831-427-4748 (FAX)
    jwatt@usgs.gov

  2. What's the catalog number I need to order this data set?

  3. What legal disclaimers am I supposed to read?

    This information is not intended for navigational purposes.
    This 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.
    Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof.

  4. How can I download or order the data?


Who wrote the metadata?

Dates:
Last modified: Jan-2013
Last Reviewed: Jan-2012
Metadata author:
U.S. Geological Survey, Coastal and Marine Geology Program
Attn: Steve Hartwell
400 Natural Bridges Drive
Santa Cruz, CA 95060-5792
US

831-460-7814 (voice)
831-427-4748 (FAX)
shartwell@usgs.gov

Metadata standard:
FGDC Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)


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