### rugged: Sea floor ruggedness analysis for the Stellwagen Bank National Marine Sanctuary region.

Metadata also available as

#### 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?

Title:
  rugged: Sea floor ruggedness analysis for the Stellwagen Bank National Marine Sanctuary region.
Abstract:
  The Terrain Ruggedness Index (TRI) calculates the average difference in elevation between a small area (a center pixel of 13 x 13 m) and its surrounding area (neighboring pixels). The TRI was applied to the digital bathymetric grids of the seafloor of the Stellwagen Bank National Marine Sanctuary region off Boston, Massachusetts to create an analysis of sea floor ruggedness.

1. How should this data set be cited?

   > Valentine, Page C. , 2005, rugged: Sea floor ruggedness analysis for the Stellwagen Bank National Marine Sanctuary region.: Scientific Investigations Map 2840, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Science Center, Woods Hole, MA.

   > Online Links:

   > - <http://pubs.usgs.gov/sim/2005/2840/data/rugged/rugged.zip>

   This is part of the following larger work.

   > Page C. Valentine, editor, 2005, Sea floor image maps showing topography, sun-illuminated topography, backscatter intensity, ruggedness, slope, and the distribution of boulder ridges and bedrock outcrops in the Stellwagen Bank National Marine Sanctuary region off Boston, Massachusetts: Scientific Investigations Map 2840, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Science Center, Woods Hole, MA.

   > Online Links:

   > - <http://pubs.usgs.gov/sim/2005/2840/>

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -70.600077
   East_Bounding_Coordinate: -70.033436
   North_Bounding_Coordinate: 42.800106
   South_Bounding_Coordinate: 42.083366

3. What does it look like?

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

   Calendar_Date: 2005
   Currentness_Reference: publication date

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

   Geospatial_Data_Presentation_Form: raster digital data

6. How does the data set represent geographic features?

   1. How are geographic features stored in the data set?

      This is a Raster data set. It contains the following raster data types:

      - Dimensions 6201 x 3631 x 1, type Grid Cell

   2. What coordinate system is used to represent geographic features?

      The map projection used is Mercator.

      Projection parameters:
        Standard_Parallel: 41.650000
        Longitude_of_Central_Meridian: -70.316667
        False_Easting: 0.000000
        False_Northing: 0.000000

      Planar coordinates are encoded using row and column
      Abscissae (x-coordinates) are specified to the nearest 13.000000
      Ordinates (y-coordinates) are specified to the nearest 13.000000
      Planar coordinates are specified in meters

      The horizontal datum used is North American Datum of 1983.
      The ellipsoid used is Geodetic Reference System 80.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257222.

7. How does the data set describe geographic features?

### Who produced the data set?

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

   - Page C. Valentine

2. Who also contributed to the data set?

3. To whom should users address questions about the data?

   Page C. Valentine
   U.S. Geological Survey
   Research Geologist
   U.S. Geological Survey
   Woods Hole, MA 02543-1598
   USA

   (508) 548-8700 x2239 (voice)
   (508) 457-2310 (FAX)
   pvalentine@usgs.gov

### Why was the data set created?

> The Terrain Ruggedness Index provides an interpretation of the seabed features in the highly variable geomorphology of the Stellwagen Bank National Marine Sanctuary region. The seabed geometry is variable due to its glacial origin and is important to the region's wide range of habitats and high biodiversity.

### How was the data set created?

1. From what previous works were the data drawn?

2. How were the data generated, processed, and modified?

   (process 1 of 1)
     The Terrian Ruggedness Index is based on an elevation index described by Riley and others (1999) where the sum change in elevation between a grid cell and its eight neighboring grid cells is calculated by squaring the eight differences in elevation, summing the squared differences, and taking the square root of the sum. Here, the index has been modified to calculate the average of the absolute values of the eight differences in elevation. The TRI was applied to the bathymetric grids by running a macro in ArcMap's Visual Basic editing environment. Artifacts of data collection were removed by hand editing and applying a mean filter (the Neighborhood Statistics function in Spatial Analyst was used to calculate a mean TRI for a 3x3 pixel template of TRI values centered over each pixel in the image).

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 observations, including topology?

### 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.

> >   Not to be used for navigational purposes.

1. Who distributes the data set? (Distributor 1 of 1)

   Page C. Valentine
   U.S. Geological Survey
   Research Geologist
   U.S. Geological Survey
   Woods Hole, MA 02543-1598
   USA

   (508) 548-8700 x2239 (voice)
   (508) 457-2310 (FAX)
   pvalentine@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 these data have been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

4. How can I download or order the data?

   - Availability in digital form:

     Data format: | ARCG Size: 85.862
     Network links: | <http://pubs.usgs.gov/sim/2005/2840/data/rugged/rugged.zip>
     Media you can order: | DVD-ROM (Density 4.75 Gbytes) (format UDF)

   - 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) ArcInfo GRID format. The user must have software capable of importing and processing the data file.

### Who wrote the metadata?

Dates:
  Last modified: 22-Aug-2005
  Last Reviewed: 22-Aug-2005
Metadata author:
  U.S. Geological Survey
  c/o Page C. Valentine
  Research Geologist
  U.S. Geological Survey
  Woods Hole, MA 02543-1598
  USA

  (508) 548-8700 x2239 (voice)
  (508) 457-2310 (FAX)
  pvalentine@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>

Generated by `mp` version 2.8.6 on Mon Aug 22 11:23:00 2005