Sediment sample information from USGS Cruise S193SC

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?

   U.S. Geological Survey, Unpublished material, Sediment sample information from USGS Cruise S193SC.

   Online Links:

   • <http://walrus.wr.usgs.gov/infobank/s/s193sc/html/s-1-93-sc.meta.html>

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -118.4014

   East_Bounding_Coordinate: -117.9998

   North_Bounding_Coordinate: 33.7302

   South_Bounding_Coordinate: 33.5909

3. What does it look like?

   Cruise_S193NC (JPG)

   Screen grab of GIS-produced sample distribution, with bathymetry and land for reference.

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

   Beginning_Date: 1993

   Ending_Date: 1993

   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 (15)

   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 0.00001. Longitudes are given to the nearest 0.00001. 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: US Geological Survey)

   Alpha numeric number based on cruise and core information

   Water depth

   Depth of water at sample site (Source: Source report)

   Range of values
   Minimum:	23
   Maximum:	230
   Units:	Meters
   Resolution:	1.0

   Gravel

   Gravel (Source: Wentworth, 1932)

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

   Sand

   Sand (Source: Wentworth 1932)

   Range of values
   Minimum:	8.29
   Maximum:	83.3
   Units:	Percent
   Resolution:	0.1

   Silt

   Silt (Source: Wentworth 1932)

   Range of values
   Minimum:	12.1
   Maximum:	60.2
   Units:	Percent
   Resolution:	0.1

   Clay

   Clay (Source: Wentworth 1932)

   Range of values
   Minimum:	3.84
   Maximum:	34
   Units:	Percent
   Resolution:	0.1

   Median

   Median grainsize (Source: Source report)

   Range of values
   Minimum:	3.42
   Maximum:	6.61
   Units:	Phi
   Resolution:	0.01

   Mean

   First moment measure: mean of grain size (Source: Source report)

   Range of values
   Minimum:	3.31
   Maximum:	6.74
   Units:	Phi
   Resolution:	0.01

   Sorting

   Second moment measure: standard deviation about the grain size mean (Source: Source report)

   Range of values
   Minimum:	0.77
   Maximum:	2.48
   Units:	Phi
   Resolution:	0.01

   Granulometric measures

   Measurement of samples into phi-size bins (Source: Source report)

   Range of values
   Minimum:	-2
   Maximum:	10
   Units:	Percent
   Resolution:	0.5

Who produced the data set?

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

2. Who also contributed to the data set?

   The USGS for collection and analysis of data. For usSEABED, digitization and formatting: K. Halimeda Kilbourne (USGS); Formatting corrections: Jane Reid (USGS) and Chris Jenkins (University of Colorado)

3. To whom should users address questions about the data?
   U.S. Geological Survey
   Coastal and Marine Geology
   Menlo Park, CA 94025
   

   1-650-329-5055 (voice)
   

Why was the data set created?

No purpose is given.

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)

   No specific information is available for cores from this cruise. General analytical techniques for the USGS Menlo Park Sediment Laboratory: Initial splits into size fractions by wet sieving using A.S.T.M. #10 (2mm) and A.S.T.M. #230 (0.063 mm) sieves. Fraction specific techniques for particle size analysis: for the coarse fraction (> 2.0 mm) is by sieve analysis and the medium fraction (2-0.063 mm) by settling tube. The fine fraction (<0.062 mm) is by pipette (Folk, 1968; Carver, 1971), hydrophotometer (Jordan and others, 1971), laser-diffraction (Beckman Coulter), or Sedigraph (Micromeretics), or combinations thereof. Settling tubes are modifications of those described by Theide, Chriss, Clauson and Swift, 1976 and are calibrated using Gibbs, 1971. Since 1998, the fine fraction (silt and clay), and occasionally up to 1 mm, is usually analyzed by the Beckman Coulter LS100Q (1 mm - 0.4 microns) and the LS230 (2 mm to 40 nanometers). Between 1993 and 1998, the fine fraction (0.063 mm to 1 micron) was generally analyzed by SediGraph (Micromeretics 5100. Between 1976 and 1995, the fine fraction was generally analyzed by hydrophotometer (Jordan and others, 1971). Data reduction, size analysis, and statistics performed by the SDSZ computer program (McHendrie, 1988). Carbon analyses by UIC Coulometrics (Joliet, IL) carbon analyzers, using protocols described in the UIC CM5012 and 5014 Coulometer instruction manuals (systems CM130, CM150, or CM250). Total carbon (TC) and total inorganic carbon (TIC) are determined by coulometric titration using Coulometer coupled to an acidification module and furnace apparatus. TC and TIC analyses are conducted separately on sediment samples. TC content is measured by combusting a sample (~20 mg) in a furnace preheated to 1000 degrees C until no more CO2 is evolved (~ five minutes). TIC content is measured using a heated perchloric acid digestion until no more CO2 is evolved (~ five minutes). Total organic carbon (TOC) content in sediments is calculated by difference (TOC = TC - TIC). For a description of USGS CMG lab procedures, see the Lab Analysis Section in: <http://walrus.wr.usgs.gov/reports/ofr91-375/>

   Person who carried out this activity:
   

   U.S. Geological Survey
   c/o Michael Torresan
   USGS Coastal and Marine Geology
   Menlo Park, CA 94025
   

   650-329-5493 (voice)
   mtorresan@usgs.gov
   

   Data sources used in this process:

   • Carver, R. E., 1971, Procedures in Sedimentary Petrography: New York, John Wiley and Sons, 653 p.
   • Folk, R. L., 1968, Petrology of Sedimentary Rocks: Austin, University of Texas Publication, 170 p.
   • Gibbs, R.J., 1972, The accuracy of particle-size analyses utilizing settling tubes: Journal of Sedimentary Petrology, v. 42, p. 141-145.
   • Gibbs, R.L., Matthews, M.D., and Link, D.A.,1971,The relationship between sphere size and settling velocity Journal of Sedimentary Research; March 1971; v. 41; no. 1; p. 7-18
   • Jordan, F.J., Jr., Fryer, G.E., and Elze, H.H., 1971, Size analysis of silt and clay by hydrophotometer: Jour. Sedimentary Petrology, v. 41, p. 489-496
   • McHendrie, G., 1988, sdsz - A Program for Sediment Size Analysis: U.S. Geological Survey, Branch of Pacific Marine Geology, Menlo Park, CA.
   • Micromeretics SediGraph 5100 instruction manual
   • Syvitski, James P., Principles, Methods, and Application of Particle Size Analysis, Cambridge University Press, Cambridge, 1991.
   • Thiede, J., Chriss, T., Clauson, M., and Swift, S.A., 1976, Settling tubes for size analysis of fine and coarse fractions of oceanic sediments: School of Oceanography, Oregon State University, Reference 76-8, 87 p.
   • UIC Coulometrics, Instruction manuals for carbon analyzer models UIC CM5012 or CM250, Joliet, IL

   Data sources produced in this process:

   • Cruise_S193SC

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 assessment made for the original data. For usSEABED, all data were digitized, visually compared to the source and corrected. Where appropriate, data were tested for completeness using MS Excel.

2. How accurate are the geographic locations?

   Navigation during all cruises was by Miniranger and provided nominal position accuracy of +/- 50 m.

3. How accurate are the heights or depths?

   Water depth determination probably by 3.5 kHz profiling systems. Subsample depths given as nearest centimeter.

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

   No estimate made for original data. For inclusion into usSEABED, all textural data in the report were included.

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: Information is available online.

Use_Constraints: Cite the U.S. Geological Survey as the originators of the data.

1. Who distributes the data set? (Distributor 1 of 1)
   U.S. Geological Survey
   Coastal and Marine Geology
   Menlo Park, CA 94025
   

   1-650-329-5055 (voice)
   

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

   Locations and descriptive data for cruise S193SC are available through the USGS Coastal and Marine Geology Team Infobank website: <http://walrus.wr.usgs.gov/infobank/s/s193sc/html/s-1-93-sc.meta.html>; Textural data are kept in the USGS CMGT archives in Menlo Park.

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 digital form:

     Data format:	Text in format ASCII Size: 1 KB
     Network links:	<http://walrus.wr.usgs.gov/infobank/s/s193sc/html/s-1-93-sc.meta.html>

   • 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)