U.S. Geological Survey Data Series 146


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Table B. Field parameters, format, units, range, meaning, and comments for EXT, PRS, CLC data files
Field Name Parameter Data Format Units, Range, Meaning Comment
Latitude Latitude Decimal 00.00000 Decimal degrees, 90° to -90° range WGS 84 Spheroid.
Longitude Longitude Decimal 000.00000 Decimal degrees, -180° to 180° range WGS 84 Spheroid.
WaterDepth Water depth Integer 00000 Meters Not always tidally correct.
SampleTop Sample top Decimal 000.00 Meters below seabed surface Sample top as noted in source report.
SampleBase Sample base Decimal 000.00 Meters below seabed surface Sample bottom as noted in source report.
SiteName Site name Character XXX: XXX Survey or laboratory code for the sampling site Not unique; site name as given in report; sometimes linked to cruise name or other information to decrease site name overlap.
DataSetKey Dataset number key Integer 000 For audit only Relational key to SRC file; SRC file contains links to source metadata.
SiteKey Site number key Integer 0000000 For audit only Relational key to other data files. Each site counted sequentially as total output; core data may have more than one sample per site.
SampleKey Sample number key Integer 0000000 For audit only Relational key to other data files. Each site counted sequentially as total output; Multiple samples may be at each site (i.e., in core).
Sampler Sampler type Character Xxxxxxxx.... Type of sampling device As given in source report; recovery (rcvy) or penetration (‘pen') length appended if given in source report. For more complete information on sampler, see source metadata.
DataType Data types Character XXX: XXX For audit principally Source data types (Table A).
Gravel Gravel Integer 000 Gravel grain size fraction, % Textural class.
Sand Sand Integer 000 Sand grain size fraction, % Textural class.
Mud Mud Integer 000 Mud grain size fraction, % Textural class.
Clay Clay Integer 000 Clay grain size fraction, % Textural class; output for 'EXT' only, as clay value can be determined only by analysis.
grain size grain size Decimal 00.00 Phi characteristic grain size Consensus of mean and median grain sizes.
Sorting Sorting Decimal 0.00 Phi grain size dispersion Standard deviation, sorting only.
SeafloorClass Sea floor class Character Xxxxx... That class (or 'facies' ) with the maximum fuzzy membership, if above 30% Output for 'PRS' table only.
ClassMbrshp Class membership Decimal 000 Fuzzy membership (%) of the class (or 'facies'), noted above Output for 'PRS' table only.
Folk classification; Shepard classification Folk classification; Shepard classification Character xx.XX...    
RockMbrshp Rock index Integer 000 Fuzzy membership (%) Membership of sample to ‘rock fuzzy set'; reported only in PRS data.
WeedMbrshp Weed index Integer 000 Fuzzy membership (%) Membership of sample to 'weed fuzzy set'; reported only in PRS data.
Carbonate Carbonate Integer 000 %; may be Fuzzy membership (PRS).  
MunsellCode Munsell color code Character XXXXX Standard alphanumeric coding of color partitioned into Hue, Value, and Chroma Ex: '5YR 6/4', See Rock-Color Chart (Geological Society of America, 1991).
OrganicCarbon Organic carbon Integer 000 % Minimum value from descriptions (PRS tables) is 0.1%.
ShearStrength Log shear strength Decimal 00.0 kiloPascals, undrained, unconfined From a variety of instrumentation.
Porosity Porosity Decimal 00.00 %  
P-waveVelocity P-wave velocity Decimal 00.0 m/sec Usually not corrected for P/T effects.
Bottom roughness Roughness Decimal 0000.00 Coded to express the height and length of the bottom feature with greatest aspect ratio In a coding that expresses the height and length of the bottom feature with greatest aspect ratio; a coded output representing the V:H of the roughness element with greatest aspect ratio, values expressed as (rounded) integer log2.
Critical shear stress Log critical shear stress Decimal 0000.00 Log10 of Tau in kPa, Log 10 of Tau in kPa, being the shear stress required to initiate easily observable erosion and transport, whether by traction or suspension; taken from a compilation of published relationships ranging from large boulder to muds, through a range of grain shapes (eg. shell).
Sample phase Where in sample the data are from Character Xxxxx.... Where sample is from Records whether the results are for the whole, bulk sediment, or just to some special part like: inside a nodule, burrow-infill, the sand fraction, porewater (chemistry), a layer in the core, a gradient observed in the core, badly preserved, a layer that is not properly located, or sample with questionable location; also may report a type of analysis or observation if that is special or potentially unrepresentative (for example, XRD, smear slide). Output is as a word-based description that may involve numerics. This field will need to be selected against when GIS mappings of the bulk sedient characters are being mapped. Only blank entries should be included in such a mapping.

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