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Open-File Report 2005-1001

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U.S. Geological Survey Open-File Report 2005-1001
USGS East-Coast Sediment Analysis: Procedures, Database, and GIS Data

EAST-COAST DATABASE Database Dictionary An integral part of any functioning database is the dictionary that explains the structure and content of the database. It contains an index and definitions of the parameters measured and lists the fields which record and qualify those parameters. Extracting data from the database is facilitated by reference to this document because it provides a means to keep track of abbreviations and the sediment fields names. Below is the database dictionary for the USGS East Coast Sediment Texture Database. Field names are listed in the order they are found in the database. Short Field Name Full-Length Field Name Field Description GROUP Group Number assigned to data based on source 1 = Samples taken before start of the joint USGS/WHOI project 2 = USGS/WHOI Atlantic Continental Margin Program stations 3 = Sediment entirely or partially analyzed, processed, or visually described by USGS Woods Hole scientists; most samples analyzed in the USGS Woods Hole Sediment Laboratory. DB_ID USGS unique sample identifier Unique identification number generated in the sedimentation laboratory of the USGS's Woods Hole Coastal and Marine Science Center. For samples analyzed after 1980 this identifier consists of 2 characters and 3 numerics (e.g. AS114).  For samples analyzed before1980, this identifier consists of 4 numerics possibly followed by as many as 2 characters. FIELD_NO Field Identifier Sample name or number as assigned in the field by the Chief Scientist. PROJECT Project name Project name or number under which samples were taken or data generated; sometimes project name indicates a more specific area. CRUISE_ID Cruise ID Name or number of cruise on which sample collected. Historically cruise identifiers were a combination of ship name, year of cruise and cruise leg. In more recent years, cruise identifier is a sequential serial number assigned to field activities within a specific year. CONTACT Principal contact Name of Principal Investigator or Chief Scientist responsible for data collection (usually first initial and last name) AREA Area General geographic area of data collection. Name is general enough to easily locate area on a state map. LATITUDE Latitude Latitude coordinate, in decimal-degrees, of sample location. South latitude recorded as negative values. LONGITUDE Longitude Longitude coordinate, in decimal degrees, of sample location. West longitude is recorded as negative values. DEPTH_M Depth or sounding in meters Measured depth, in meters, of water overlying sediment at sample time. Depth value is not corrected for tides. T_DEPTH Top depth Top depth of sample, in centimeters, below the sediment-water interface. B_DEPTH Bottom depth Bottom depth of sample, in centimeters, below the sediment-water interface. DEVICE Sampling device Device used to collect the sample. MONTH_COLL Month collected Calendar month sample collected. DAY_COLL Day collected Calendar day sample collected. YEAR_COLL Year collected Calendar year sample collected. MONTH_ANAL Month analyzed Calendar month sample completed analysis. DAY_ANAL Day analyzed Calendar day sample completed analysis. YEAR_ANAL Year analyzed Calendar year sample completed analysis. WEIGHT Weight Weight of dry sample in grams. GRAVEL_PCT %Gravel Gravel content in percent dry weight of the sample (particles with nominal diameters greater than 2 mm; -1 phi and larger. SAND_PCT %Sand Sand content in percent dry weight of sample (particles with nominal diameters less than 2 mm but greater than or equal to 0.0625 mm; 0 phi through 4 phi). SILT_PCT %Silt Silt content in percent dry weight of the sample (particles with nominal diameters less than 0.0625 mm but greater than or equal to 0.004 mm; 5 phi through 8 phi, inclusive). CLAY_PCT %Clay Clay content in percent dry weight of the sample (particles with nominal diameters less than 0.004 mm; less than 8 phi). CLASSIFICATION Classification Sediment description based on rigorous definition usually Shepard (1954) as modified by Schlee and Webster (1967), Schlee (1973), and Poppe and others (2005). Classes include: GRAVEL – gravel equal to or greater than 50 percent GRAVELLY SEDIMENT – gravel equal to or greater than 10 percent, but less than 50 percent. SAND – sand equal to or greater than 75 percent SILTY SAND - sand less than 75 percent and equal to or greater than 50 percent, silt greater than clay, and clay less than 20 percent CLAYEY SAND - sand less than 75 percent and equal to or greater than 50 percent, clay greater than silt, and silt less than 20 percent SILT - silt equal to or greater than 75 percent SANDY SILT – silt less than 75 percent and equal to or greater than 50 percent, sand greater than clay, and clay less than 20 percent CLAYEY SILT - silt less than 75 percent and equal to or greater than 50 percent, clay greater than sand, and sand less than 20 percent CLAY – clay equal to or greater than 75 percent SANDY CLAY - clay less than 75 percent and equal to or greater than 50 percent, sand greater than silt, and silt less than 20 percent SILTY CLAY - clay less than 75 percent and equal to or greater than 50 percent, silt greater than sand, and sand less than 20 percent SAND SILT CLAY – clay, sand, and silt greater than 20 percent each MEDIAN Median Middle point in the grain size distribution in phi units. MEAN Mean Average value in the grain size distribution in phi units. STDEV Standard deviation (sorting) Standard deviation (root mean square of the deviations) of the grain size distribution in phi units. SKEWNESS Skewness Skewness (deviation from symmetrical form) of the grain size distribution. KURTOSIS Kurtosis Kurtosis (degree of curvature near the mode) of the grain size distribution. MODE1CLASS Mode 1 class First mode (particle size that occurs the most number of times) in phi units. MODE1FREQ Mode 1 strength Modal strength of the first mode in percent. MODE2CLASS Mode 2 class Second mode in phi units. MODE2FREQ Mode 2 strength Modal strength of the second mode in percent. MODE3CLASS Mode 3 class Third mode in phi units. MODE3FREQ Mode 3 strength Modal strength of the third mode in percent. NMODES No. of modes Number of modes. PHIm5 -5 Phi Weight percent of the sample in the -5 phi fraction and coarser (nominal diameter of particles greater than or equal to 32mm); very coarse pebbles to cobbles PHIm4 -4 Phi Weight percent of the sample in the -4 phi fraction (nominal diameter of particles greater than or equal to 16mm, but less than 32mm); coarse pebbles. PHIm3 -3 Phi Weight percent of the sample in the -3 phi fraction (nominal diameter of particles greater than or equal to 8mm, but less than 16mm); medium pebbles. PHIm2 -2 Phi Weight percent of the sample in the -2 phi fraction (nominal diameter of particles greater than or equal to 4mm, but less than 8mm); fine pebbles. PHIm1 -1 Phi Weight percent of the sample in the -1 phi fraction (nominal diameter of particles greater than or equal to2mm, but less than 4mm); very fine pebbles (granules). PHI_0 0 Phi Weight percent of the sample in the 0 phi fraction (nominal diameter of particles greater than or equal to 1mm, but less than 2mm); very coarse sand. PHI_1 1 Phi Weight percent of the sample in the 1 phi fraction (nominal diameter of particles greater than or equal to 0.5mm, but less than 1mm); coarse sand. PHI_2 2 Phi Weight percent of the sample in the 2 phi fraction (nominal diameter of particles greater than or equal to 0.25mm, but less than 0.5mm); medium sand. PHI_3 3 Phi Weight percent of the sample in the 3 phi fraction (nominal diameter of particles greater than or equal to 0.125mm, but less than 0.25mm); fine sand. PHI_4 4 Phi Weight percent of the sample in the 4 phi fraction (nominal diameter of particles greater than or equal to 0.0625mm, but less than 0.125mm); very fine sand. PHI_5 5 Phi Weight percent of the sample in the 5 phi fraction (nominal diameter of particles greater than or equal to 0.031mm, but less than 0.0625mm); coarse silt. PHI_6 6 Phi Weight percent of the sample in the 6 phi fraction (nominal diameter of particles greater than or equal to 0.016mm, but less than 0.031mm); medium silt. PHI_7 7 Phi Weight percent of the sample in the7 phi fraction (nominal diameter of particles greater than or equal to 0.008mm, but less than 0.016mm); fine silt. PHI_8 8 Phi Weight percent of the sample in the 8 phi fraction (nominal diameter of particles greater than or equal to 0.004mm, but less than 0.008mm); very fine silt. PHI_9 9 Phi Weight percent of the sample in the 9 phi fraction (nominal diameter of particles greater than or equal to 0.002mm, but less than 0.004mm); coarse clay. PHI_10 10 Phi Weight percent of the sample in the 10 phi fraction (nominal diameter of particles greater than or equal to 0.001mm, but less than 0.002mm); medium clay. PHI_11 11 Phi Weight percent of the sample in the 11 phi fraction and finer (nominal diameter of particles less than 0.0001mm); fine clay. ANALYST Analyst Name (usually first initial and last name) of person who performed the grain size or physical properties analysis. ANAL_COMM Comments on analyses Any further information about sediment analysis for all or specific parameters in this table. LITHOLOGY Lithology General lithologic description of sample. COMMENTS Comments Comments on sample collection or lithology.
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