GMX_EXT: usSEABED EXTracted data for the entire U.S. Gulf of Mexico and Caribbean (Puerto Rico and U.S. Virgin Islands)

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, and Colorado, University of , 2006, GMX_EXT: usSEABED EXTracted data for the entire U.S. Gulf of Mexico and Caribbean (Puerto Rico and U.S. Virgin Islands):.

   Online Links:

   • <https://pubs.usgs.gov/ds/2006/146/data/gmx_ext.zip>
   • <https://pubs.usgs.gov/ds/2006/146/htmldocs/data_cata.htm>

   This is part of the following larger work.

   Buczkowski, B.J., Reid, J.A., Jenkins, C.J., Reid, J.M., Williams, S.J., and Flocks, J.G., 2006, usSEABED: Gulf of Mexico and Caribbean (Puerto Rico and U.S. Virgin Islands) Offshore Surficial Sediment Data Release: Data Series 146, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Science Center, Woods Hole, MA.

   Online Links:

   • <https://pubs.usgs.gov/ds/2006/146/>

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -97.731850

   East_Bounding_Coordinate: -63.800000

   North_Bounding_Coordinate: 30.808300

   South_Bounding_Coordinate: 16.666670

3. What does it look like?

   <https://pubs.usgs.gov/ds/2006/146/data/gmx_ext.jpg> (JPEG)

   Image map showing extent of data layer coverage

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

   Calendar_Date: 2006

   Currentness_Reference: publication date

5. What is the general form of this data set?

   Geospatial_Data_Presentation_Form: vector digital data

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 (51290)

   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 0.000000. Longitudes are given to the nearest 0.000000. Latitude and longitude values are specified in Decimal degrees.

      The horizontal datum used is North American Datum of 1927.
      The ellipsoid used is Clarke 1866.
      The semi-major axis of the ellipsoid used is 6378206.400000.
      The flattening of the ellipsoid used is 1/294.978698.
      

7. How does the data set describe geographic features?

   gmx_ext

   FID

   Internal feature number. (Source: ESRI)

   Sequential unique whole numbers that are automatically generated.

   Shape

   Feature geometry. (Source: ESRI)

   Coordinates defining the features.

   LATITUDE

   Latitude coordinate of sample location (Source: source data)

   Range of values
   Units:	decimal degrees

   LONGITUDE

   Longitude coordinate of sample location (Source: source data)

   Range of values
   Units:	decimal degrees

   WATERDEPTH

   measured water depth for site (usually uncorrected) (Source: source data)

   Range of values
   Units:	meters

   SAMPLETOP

   measured subbottom depth information for each point sample

   Range of values
   Units:	meters

   SAMPLEBASE

   measured subbottom depth information for each point sample

   Range of values
   Units:	meters

   SITENAME

   Survey or laboratory code for site (non-unique)

   DATASETKEY

   Unique sequential numeric key to SRC file (Source: dbSEABED processing software)

   SITEKEY

   Unique sequential numeric key to SRC file (Source: dbSEABED processing software)

   SAMPLEKEY

   Unique sequential numeric key to SRC file (Source: dbSEABED processing software)

   SAMPLER

   Equipment used to collect samples (Source: Original data source)

   DATATYPES

   Type of data that were used to derive values held in characterization

   Value	Definition
   ACU	Acoustic Properties
   CMP	Sediment Composition
   COL	Color
   GTC	Geotechnical Properties
   GRZ	Grain Size
   TXR	Texture
   TXG	Texture (Graphic)
   LTH	Lithology

   GRAVEL

   Gravel grainsize fraction (Source: Original data source)

   Range of values
   Minimum:	0
   Maximum:	100
   Units:	percent
   Resolution:	1

   SAND

   Sand grainsize fraction (Source: Original data source)

   Range of values
   Minimum:	0
   Maximum:	100
   Units:	percent
   Resolution:	1

   MUD

   Mud grainsize fraction (Source: Original data source)

   Range of values
   Minimum:	0
   Maximum:	100
   Units:	percent
   Resolution:	1

   CLAY

   Clay grainsize fraction (Source: Original data source)

   Range of values
   Minimum:	0
   Maximum:	100
   Units:	percent
   Resolution:	1

   GRAINSIZE

   Phi characteristic grainsize

   Range of values
   Minimum:	-7.3
   Maximum:	12
   Units:	phi
   Resolution:	0.1

   SORTING

   Phi grainsize dispersion; standard deviation sorting only

   Range of values
   Minimum:	0
   Maximum:	6
   Units:	phi
   Resolution:	0.1

   LGCRSHST

   Log Critical Shear Stress, Log10 of Tau in kPa, being the Shear Stress required to initiate easily observable erosion and transport, whether by traction or suspension

   Range of values
   Units:	kPa

   SEABEDCLS

   Seabed class; (Facies) with the maximum Fuzzy Membership value > 30% (Source: dbSEABED processing software)

   CLSMSHP

   Class membership; fuzzy membership (%) of above Class (Facies) (Source: dbSEABED processing software)

   ROCKMSHP

   Rock membership; fuzzy membership (%) reflecting percent exposure of rock (Source: dbSEABED processing software)

   Value	Definition
   -99	no data

   WEEDMSHP

   Weed membership; fuzzy membership (%) reflecting percent abundance of seaweed and seagrass (Source: dbSEABED processing software)

   Value	Definition
   -99	no data

   CARBONATE

   Carbonate, including finest to coarsest sampled fractions

   MUNSLCODE

   Munsell color code (Source: GSA Rock-Color Chart, 1991)

   non-unique code based on HVC (Hue, Value, Chroma)

   ORGCARBON

   organic carbon in the sample

   Range of values
   Minimum:	0
   Maximum:	100
   Units:	percent

   LGSHEARSTR

   Undrained compressive shear strength, Log10 of KiloPascals (Source: dbSEABED processing software)

   Value	Definition
   -99	no data

   POROSITY

   Void volume (Source: dbSEABED processing software)

   Range of values
   Units:	percent

   PWAVEVEL

   Compressional wave velocity (Source: dbSEABED processing software)

   Range of values
   Units:	meters/second

   ROUGHNESS

   A coded output representing the V:H of the roughness element with greatest aspect ratio (Source: dbSEABED processing software)

   Range of values
   Units:	values expressed as (rounded) integer log2 of V and H in cm

   SAMPLEPHAS

   Sample Phase; records whether the results are for the whole, bulk sediment or just to some special part (Source: dbSEABED processing software)

   Range of values
   Units:	Output 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.

   FOLKCODE_F

   Entity_and_Attribute_Overview:

   Values of -99 for any field are indications that there was no data available.

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
   • University of Colorado

2. Who also contributed to the data set?

   We thank the following interns for their assistance in data entry, coding, and data testing: Viness Ubert, Emma Mitchell, Emily Denham ,Shea Quinn and Ariadne Prior-Grosch.

3. To whom should users address questions about the data?
   Brian Buczkowski
   U.S. Geological Survey
   Core Curator and Data Management Specialist
   384 Woods Hole Road
   Woods Hole, MA 02543-1598
   USA
   

   (508) 548-8700 x2361 (voice)
   (508) 457-2310 (FAX)
   bbuczkowski@usgs.gov
   

Why was the data set created?

To build a digital mapping of the character of the seabed on regional, national and global scales. These data are intended for science researchers, students, policy makers, and the general public. The data can be used with geographic information systems (GIS) software to display geologic and oceanographic information.

How was the data set created?

1. From what previous works were the data drawn?

   (source 1 of 1)

   Type_of_Source_Media: various hard copy documents and digital files

   Source_Scale_Denominator:

   See separate listing within this publication for specific sources and associated metadata

   Source_Contribution:

   point locations, descriptions and analytical data on many different types of sediment and rock materials and benthos

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?

   Accuracy of each attribute is dependent on the accuracy of the lineage data.

2. How accurate are the geographic locations?

   Locational accuracy is dependent on the accuracy of the navigational technique from the individual data sources and may vary widely (e.g., from 0.005km (differential GPS) in more recent surveys to greater than 2 km based on radar, Loran, or dead reckoning in older surveys.) Users of the data should use their own criteria for assessing the accuracy of the locations.

3. How accurate are the heights or depths?

   Locational accuracy is dependent on the accuracy of the navigational technique from the individual data sources. Users of the data should use their own criteria for assessing the accuracy of the locations.

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

   Additional useable data may exist in this area; the authors appreciate any information and leads.

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

   Data in usSEABED are based on the observations and analyses of others, filtered through a unifying and mining software. Each source report varies in type of information/data recorded and format. Only those observations that are recorded can be filtered and mined; only presence (not absence) or information can be noted.

How can someone get a copy of the data set?

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

Access_Constraints: None

Use_Constraints:

Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey (USGS) as the source of this information.

1. Who distributes the data set? (Distributor 1 of 1)
   Brian Buczkowski
   U.S. Geological Survey
   Core Curator and Data Management Specialist
   384 Woods Hole Rd.
   Woods Hole, MA 02543-1598
   

   (508) 548-8700x2361 (voice)
   (508) 457-2310 (FAX)
   bbuczkowski@usgs.gov
   

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

   Downloadable Data

3. What legal disclaimers am I supposed to read?

   Although this data set has been used by the U.S. Geological Survey (USGS), no warranty, expressed or implied, is made by the USGS as to the accuracy of the data and/or related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these data or related materials. Trade, firm, or product names and other references to non-USGS products and services are provided for information only and do not constitute endorsement or warranty, express or implied, by the USGS, USDOI, or U.S. Government, as to their suitability, content, usefulness, functioning, completeness, or accuracy.

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

     Data format:	Text file containing data input to usSEABED. Fields are comma separated values. First record of file contains field names. in format ASCII Size: 6.61 MB
     Network links:	<https://pubs.usgs.gov/ds/2006/146/data/gmx_ext.txt> <https://pubs.usgs.gov/ds/2006/146/htmldocs/data_cata.htm>

     Data format:

     The SHP file contains the geospatial data. The SHX file contains the index of the geospatial data. The DBF file contains the attribute data in dBASE format. The PRJ file contains the coordinate system information (optional). The AVL file contains the legend information (optional). The SBN and SBX files contain the spatial index of the geospatial data (optional). The XML file contains the metadata describing the data set <data set name>.shp.xml. An ASCII version of the metadata file. A browse graphic showing the data layer coverage and extent (optional). in format SHP ESRI Shapefile

     Network links:

     <https://pubs.usgs.gov/ds/2006/146/data/gmx_ext.zip> <https://pubs.usgs.gov/ds/2006/146/htmldocs/data_cata.htm>

   • Cost to order the data: None

5. What hardware or software do I need in order to use the data set?

   These data are available in Environmental Systems Research Institute (ESRI) shapefile format. The user must have ArcGIS® or ArcView® 3.0 or greater software to read and process the data file. In lieu of ArcView or ArcGIS, the user may utilize another GIS application package capable of importing the data. A free data viewer, arcexplorer, capable of displaying the data is available from ESRI at www.esri.com.

Who wrote the metadata?

Dates:

Last modified: 09-Feb-2006

Metadata author:

Brian Buczkowski
U.S. Geological Survey
Core Curator and Data Management Specialist
384 Woods Hole Rd.
Woods Hole, MA 02543-1598

(508) 548-8700x2361 (voice)
(508) 457-2310 (FAX)
bbuczkowski@usgs.gov

Metadata standard:

FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)

Metadata extensions used:

• <http://www.esri.com/metadata/esriprof80.html>