usSEABED: East Coast Offshore Surficial Sediment Data Release, Table B

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U.S. Geological Survey Data Series 118, usSEABED: Atlantic Coast Offshore Surficial Sediment Data Release, version 1.0

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	Seafloor 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 (Goddard and others, 1951).
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.