Holocene stratigraphy and sedimentation on the northern California continental shelf

Frequently-anticipated questions:

• What does this data set describe?
  1. How should this data set be cited?
  2. What geographic area does the data set cover?
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
• Who produced the data set?
  1. Who are the originators of the data set?
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
• Why was the data set created?
• How was the data set created?
  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
  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?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
  5. How consistent are the relationships among the data, including topology?
• How can someone get a copy of the data set?
  1. Are there legal restrictions on access or use of the data?
  2. Who distributes the data?
  3. What's the catalog number I need to order this data set?
  4. What legal disclaimers am I supposed to read?
  5. How can I download or order the data?
• Who wrote the metadata?

What does this data set describe?

1. How should this data set be cited?

   Demirpolat, Suleyman, 1981, Holocene stratigraphy and sedimentation on the northern California continental shelf: University of Washington, Seattle, WA.

   Other_Citation_Details: Master's thesis

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -123.750

   East_Bounding_Coordinate: -123.052

   North_Bounding_Coordinate: 38.800

   South_Bounding_Coordinate: 38.062

3. What does it look like?

   Demirpolat_MS_1981 (.jpg)

   Sample distribution with coastline and bathymetry for reference.

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

   Beginning_Date: 1979

   Ending_Date: 1981

   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):

      • Entity point (26)

   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: University of Washington)

   Alpha numeric code based on cruise identification and sample number.

   Sampler

   Sampler type (Source: Source report)

   Value	Definition
   Gr	Grab sample
   Bx	Box core sample
   Ps	Piston core

   Water depth

   Water depth (Source: Source report)

   Range of values
   Minimum:	33
   Maximum:	154
   Units:	Meters
   Resolution:	1.0

   Gravel

   Gravel (Source: Krumbein and Pettijohn, 1938)

   Range of values
   Minimum:	0
   Maximum:	19.15
   Units:	Percent
   Resolution:	0.01

   Sand

   Sand (Source: Krumbein and Pettijohn, 1938)

   Range of values
   Minimum:	3.75
   Maximum:	90.78
   Units:	Percent
   Resolution:	0.01

   Silt

   Silt (Source: Krumbein and Pettijohn, 1938)

   Range of values
   Minimum:	5.85
   Maximum:	76.25
   Units:	Percent
   Resolution:	0.01

   Clay

   Clay (Source: Krumbein and Pettijohn, 1938)

   Range of values
   Minimum:	2.21
   Maximum:	45.99
   Units:	Percent
   Resolution:	0.01

   Mode

   Mode of grainsize distribution (Source: Source report)

   Range of values
   Minimum:	2.75
   Maximum:	9.0
   Units:	Phi
   Resolution:	0.25

   Median

   Median grainsize (Source: Inman, 1952)

   Range of values
   Minimum:	3.01
   Maximum:	7.64
   Units:	Phi
   Resolution:	0.01

   Mean

   Mean grainsize (Source: Inman, 1952)

   Range of values
   Minimum:	1.59
   Maximum:	7.6
   Units:	Phi
   Resolution:	0.01

   Sorting

   Standard deviation of grainsize (Source: Inman, 1952)

   Range of values
   Minimum:	0.21
   Maximum:	3.71
   Units:	Phi
   Resolution:	0.01

   First skewness

   First skewness of grainsize (Source: Inman, 1952)

   Range of values
   Minimum:	-0.44
   Maximum:	0.9
   Units:	Unitless
   Resolution:	0.01

   Second skewness

   Second skewness of grainsize (Source: Inman, 1952)

   Range of values
   Minimum:	-0.28
   Maximum:	6.36
   Units:	Unitless
   Resolution:	0.01

   Kurtosis

   Kurtosis of grainsize distribution (Source: Inman, 1952)

   Range of values
   Minimum:	0.61
   Maximum:	6.44
   Units:	Unitless
   Resolution:	0.01

   Light minerals in sand fraction

   Minerals in sand fraction with density < 2.85 g/cm3 (Source: Source report)

   Range of values
   Minimum:	90.5
   Maximum:	98.6
   Units:	Percent
   Resolution:	0.01

   Magnetic minerals in sand fraction

   Minerals in sand fraction attracted to hand magnet of unknown strength. (Source: Source report)

   Range of values
   Minimum:	0.07
   Maximum:	1.1
   Units:	Percent
   Resolution:	0.01

   Heavy minerals in sand fraction

   Minerals in sand fraction with density > 2.85 g/cm3 (Source: Source report)

   Range of values
   Minimum:	1.24
   Maximum:	8.8
   Units:	Percent
   Resolution:	0.01

   Mineral identification heavy minerals

   Mineral identification in heavy mineral portion of sand fraction (Source: Source report)

   Percents of biotite, glauconite, glaucophane, hornblende, and unidentified heavy minerals.

   Mineral identification; clay minerals

   Mineral identification in clay portion (Source: Source report)

   Percents of chlorite, illite, kaolinite, montmorillonite.

Who produced the data set?

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

2. Who also contributed to the data set?

   For usSEABED: Suleyman Demirpolat at the University of Washington for the collection and analysis of data. For inclusion into usSEABED: Digitization: K. Halimeda Kilbourne and Jennifer Mendonca (USGS) and Mark Zimmermann (NOAA) Formatting corrections: Jane Reid (USGS) and Chris Jenkins (University of Colorado).

3. To whom should users address questions about the data?
   University of Washington
   P.O. Box 357940
   Seattle, WA 98195
   

   206-543-5060 (voice)
   

Why was the data set created?

"The purpose of this study was (1) to describe the areal distribution of the sediments and their textural variation, and use these variations as indicators of sedimentary processes on the continental shelf, and (2) to distinguish the modern and relict characteristics of the northern California continental shelf."

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)

   For textural analyses, the coarse sediment (greater than 0.062 mm) was dry sieved using 1/4 phi interval sieves and then weighed. The fine sediment (separated from the coarse sediment by wet-sieving) was pipetted on 1/2 phi intervals for the silt fraction and 1 phi-unit intervals for the clay. A split of 2-3 grams of the bulk sand fraction was used for heavy mineral analysis. Bromoform (sp. Gravity = 2.85 g/cm3) was added, centrifuged, filtered and rinsed. Magnetic minerals were separated using a hand magnet,and grain mounts were examined using a petrographic microscope; only the selected heavy minerals were counted. Clays were collected by repeated sedimentation and decantation using Millipore filters and glass slides. X-Ray diffraction was done on a Norelco diffractometer with a scintillation detector using copper k-alpha radiation and 40 kv and 20 ma and a graphite Monochrometer

   Person who carried out this activity:
   

   University of Washington
   P.O. Box 357940
   Seattle, WA 98195
   

   206-543-5060 (voice)
   

   Data sources produced in this process:

   • Demirpolat_MS_1981

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?

   Navigation method unknown; no assessment made for location accuracy. Locations given to degrees minutes, tenths

3. How accurate are the heights or depths?

   Depth determination method unknown; no assessment made for accuracy. Depths given in meters

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

   All appendices (1 through 5) were digitized.

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

   Data fall within normal ranges for the given parameters. One typo of light mineral percentage was changed in usSEABED from 44.65% to 94.65% to be consistent with other measurements.

How can someone get a copy of the data set?

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

Access_Constraints:

None. Thesis is available at the USGS Library and other libraries.

Use_Constraints:

Cite Suleyman Demirpolat and the University of Washington as originators of the data.

1. Who distributes the data set? (Distributor 1 of 2)
   University of Washington
   P.O. Box 357940
   Seattle, WA 98195
   

   206-543-5060 (voice)
   

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

   depends on library

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?
   • Availability in non-digital form:

     Report is available at libraries and the University of Washington.

   • Cost to order the data: None

   ---

1. Who distributes the data set? (Distributor 2 of 2)
   U.S. Geological Survey
   345 Middlefield Road
   Menlo Park, CA 94025
   

   650.329.5026 (voice)
   men_lib@usgs.gov
   

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

   Demirpolat MS thesis 1981

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 the limitations of the data due to possible imprecision due to navigational inaccuracies, statistical limitations, and digitizing errors.

4. How can I download or order the data?
   • Availability in non-digital form:

     Report is available for viewing or checkout at the USGS library, Menlo Park, and at other libraries.

   • Cost to order the data: None

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)