Holocene sedimentation and potential placer deposits on the continental shelf off the Rogue River

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What does this data set describe?

Title:
Holocene sedimentation and potential placer deposits on the continental shelf off the Rogue River
Abstract:
Changes in sea level during the past 20,000 years are recorded in sediments taken from the continental shelf off the Rogue River, Oregon. Sea level has risen approximately 125 m during the Holocene (Curray, 1965) and the general transgression has been interrupted by several stillstands and minor regressions. Box core samples taken in the area of investigation depict the nature of sedimentation during the last rise of sea level as well as present-day equilibrium sediment relationships. Three sediment facies, a recent fine-grained mud, a basal transgressive sand, and an intermediate sediment, believed to be a mixture of the other two, are defined on the shelf on the basis of textural parameters. The mud facies dominates surface sediment on the central shelf while the sand facies is the most commonly exposed on both the inner and outer shelf. The percentage of sand generally increases with depth in the box cores, often producing a change in sediment facies with depth and demonstrating the transgressive nature of the sediments. Grain-size analysis of the sand fraction of the offshore sediments reveals that offshore sands are finer-grained and better sorted than those occurring on the present beaches. The offshore sands most likely represent relict nearshore deposits and not ancient beach sands which would occur lower in the sediment sequence. High concentrations of heavy minerals are found in the sand fraction of the offshore sediments as well as in beach sands in the area. Brief stillstands of sea level may be reflected in depths where the offshore sands contain anomalously high percentages of heavy minerals. Opaque minerals, chiefly magnetite, occur in placer accumulations on the present beaches and high percentages of these minerals in the offshore sands may be indicative of submerged beach environments associated with stillstands of sea level. The magnetite may be concentrated in sufficient quantity in the placers to produce detectable magnetic anomalies, several of which have been recorded in the area. Other lines of evidence used to determine the depths of probable stillstands of sea level are bathymetric relief, the distribution of shallow water fauna in sediments from deep water, and the distribution of rounded gravels on the shelf. A compilation of the several lines of evidence suggest several stillstands of sea level associated with the Holocene transgression occurring at depths of 18, 29, 47, 71, 84, 102, and 150 meters.
Supplemental_Information:
U.S.Geological Survey research grant 14-08-0001-10766; Data digitized in 2003 by the USGS for inclusion into usSEABED. (<http://walrus.wr.usgs.gov/usseabed>)
  1. How should this data set be cited?

    Chambers, David Marshall , 1969, Holocene sedimentation and potential placer deposits on the continental shelf off the Rogue River: Oregon State University, Corvallis, OR.

    Other_Citation_Details: Masters thesis

  2. What geographic area does the data set cover?

    West_Bounding_Coordinate: -124.767
    East_Bounding_Coordinate: -124.415
    North_Bounding_Coordinate: 42.633
    South_Bounding_Coordinate: 42.333

  3. What does it look like?

    Chambers_MS_1968 (JPG)
    Screen grab of sample distribution, coastline, and bathymetry

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

    Beginning_Date: 1965
    Ending_Date: 1968
    Currentness_Reference: Publication date

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

    Geospatial_Data_Presentation_Form: Paper

  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):

      • Point (112)

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

      Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.00167. Longitudes are given to the nearest 0.00167. Latitude and longitude values are specified in Decimal degrees.

  7. How does the data set describe geographic features?

    Point
    SDTS point (Source: Source report)

    Sample number
    Sample number (Source: Oregon State University)

    Alpha numeric code based on year, month, sample number, and subcore information.

    Subsample depth
    Subsample depth (Source: Source report)

    Range of values
    Minimum:0
    Maximum:0.77
    Units:Meter
    Resolution:0.01

    Gravel
    Amount of gravel in sample (Source: Wentworth 1938)

    No gravel sediment recorded but mentioned in text (p. 27) at water depths of 46, 48, 71, 104, 100, and 123 m.

    Sand
    Amount of sand in sample (Source: Wentworth 1938)

    Range of values
    Minimum:6.1
    Maximum:100
    Units:Percent
    Resolution:0.1

    Silt
    Amount of silt in sample (Source: Wentworth 1938)

    Range of values
    Minimum:0
    Maximum:68.9
    Units:Percent
    Resolution:0.1

    Clay
    Amount of clay in sample (Source: source report)

    Range of values
    Minimum:0
    Maximum:42.1
    Units:percent
    Resolution:0.0001

    Mean
    Mean grain size (Source: Folk and Ward 1957)

    Range of values
    Minimum:2.88
    Maximum:7.39
    Units:Phi
    Resolution:0.01

    Standard deviation
    Standard deviation of grain size (Source: Folk and Ward 1957)

    Range of values
    Minimum:0.29
    Maximum:5.2
    Units:Phi
    Resolution:0.01

    Skewness
    Skewness of grain size (Source: Folk and Ward 1957)

    Range of values
    Minimum:-0.21
    Maximum:0.84
    Units:Unitless
    Resolution:0.01

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?

    David Marshall Chambers at Oregon State University for the collection and analysis of data. For inclusion into usSEABED: Digitization: Jennifer Mendonca (USGS); Formatting corrections: Jane Reid (USGS) and Chris Jenkins (University of Colorado)

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

    Oregon State University
    College of Oceanic and Atmospheric Sciences
    Corvallis, OR 97331-5503

    541-737-3504 (voice)

Why was the data set created?

The purpose of [this] investigation is to located the positions of the stillstands of sea level on the continental shelf off the Rogue River, Oregon, and thereby outline the Holocene history of sedimentation in this area.

How was the data set created?

  1. From what previous works were the data drawn?

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

    Date: Unknown (process 1 of 1)
    Grain size analysis of the fine fraction (<0.062mm) was carried out by the hydrometer method as outlined by the American Society for Testing and Materials (1965). When the amount of sample was small, the silt and clay fractions were analyzed by the pipette method (Krumbein and Pettijohn, 1938). After the hydrometer or pipette analyses were completed, the samples were washed through a 0.062mm sieve and the sand fraction was analyzed using the Emery (1938) settling tube as modified by Poole (1957).

    Person who carried out this activity:

    College of Oceanic and Atmospheric Sciences, Oregon State University
    104 COAS Admin Bldg
    Corvallis, OR 97331-5503

    541-737-3504 (voice)

    Data sources used in this process:
    • American Society for Testing and Materials, 1965
    • Krumbein and Pettijohn, 1938
    • Emery, 1938
    • Poole, 1957

    Data sources produced in this process:

    • Chambers_MS_1968

  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?

    No estimate made for the accuracy of the data in the original report. Data digitized by the USGS and partners were visually compared to the source data, and corrected. Where appropriate, data were tested for completeness using MS Excel. Locations checked using GIS.

  2. How accurate are the geographic locations?

    No navigational techniques given in report. Positions given to minute-tenths.

  3. How accurate are the heights or depths?

    Depth determination technique not given in report. Water depths recorded to nearest meter; subsample depths given to nearest centimeter.

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

    Location, textural, and statistical data digitized for complete samples (excluding gravel) from Appendices I and II. Appendices III (textural analysis including statistics for the sand fraction only); and IV (heavy mineral percentages of the sand fraction and percent opaque minerals of heavy mineral fraction) not digitized.

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

    Data fall within normal ranges for the given parameters.

How can someone get a copy of the data set?

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

Access_Constraints: Thesis is available at the USGS library and at other libraries.
Use_Constraints: Cite D.M. Chambers as originator of the data.

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

    College of Oceanic and Atmospheric Sciences, Oregon State University
    104 COAS Admin Bldg
    Corvallis, OR 97331-5503

    541-737-3504 (voice)

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

    D.M. Chambers_Masters_thesis 1969

  3. What legal disclaimers am I supposed to read?

    Although this dataset has been used by the USGS, no warranty, expressed or implied, is made by the USGS as to the accuracy of the data. Users of the data should be aware of limitations of the data due to possible imprecision due to navigational inaccuracies and limitations of the statistical data.

  4. How can I download or order the data?

  5. What hardware or software do I need in order to use the data set?

    None

Who wrote the metadata?

Dates:
Last modified: 2005
Metadata author:
U.S. Geological Survey
c/o Jane A. Reid
Geologist
400 Natural Bridges Drive
Santa Cruz, CA 95060

831-427-4727 (voice)
jareid@usgs.gov

Contact_Instructions: Email preferred
Metadata standard:
CSDGM Version 2 (FGDC-STD-001-1998)

Generated by mp version 2.8.17 on Tue May 16 20:33:44 2006