one meter bathymetry contours offshore Sarasota, FL

Metadata also available as - [Outline] - [Parseable text] - [XML]

Frequently anticipated questions:

What does this data set describe?

Title: one meter bathymetry contours offshore Sarasota, FL
Abstract:
The U.S. Geological Survey, in cooperation with the University of South Florida and Eckerd College, completed a bathymetric, sidescan sonar, high-resolution seismic-reflection, and surface sediment sampling survey of the inner shelf environment along the western Florida coast. The survey area extends 15km from Sarasota Point to Buttonwood Harbor. This study is part of a larger program initiated by the U.S. Geological Survey to map the geologic framework and monitor the modern processes that affect the western Florida coastal zone. This portion of the project included a reconnaissance high-resolution seismic and side-scan sonar surveys of the entire study area, detailed mapping to identify patterns of hard grounds and sediment cover, and coring of sediments to document historical development of the inner shelf and coastal system.
Supplemental_Information:
Isobath contours range from 4 to 12m. Depth values were recorded in decimeters to provide somewhat more data resolution in the shallow field study. Because values are recorded in decimeters a depth value of 80 would be equivalent to a depth of 8.0m. These data were collected on U.S. Geological Survey field activity 1995-004-FA (BLWS 95-04) https://cmgds.marine.usgs.gov/services/activity.php?fan=1995-004-FA .
  1. How might this data set be cited?
    Twichell, Dave, 1999, one meter bathymetry contours offshore Sarasota, FL: Open-File Report 99-396, U.S. Geological Survey, Coastal and Marine Geology Team, Woods Hole Field Center.

    Online Links:

    This is part of the following larger work.

    Twichell, David C., and Paskevich, Valerie F., 1999, Bathymetry, sidescan sonar image, surface sediments, and surfical geological map of the inner shelf off Sarasota, Florida: Preliminary discussion and GIS database release: Open-File Report 99-396, U.S. Geological Survey, Reston, VA.

    Online Links:

    Other_Citation_Details:
    Suggested citation: Twichell, D.C., and Paskevich, V.F., 1999, Bathymetry, sidescan sonar image, surface sediments, and surfical geological map of the inner shelf off Sarasota, Florida— Preliminary discussion and GIS database release: U.S. Geological Survey Open-File Report 99-396, https://doi.org/10.3133/ofr99396
  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -82.7306
    East_Bounding_Coordinate: -82.5687
    North_Bounding_Coordinate: 27.3855
    South_Bounding_Coordinate: 27.2209
  3. What does it look like?
    https://pubs.usgs.gov/of/1999/of99-396/htmldocs/images/covrgs/onemeter.gif (1m bathymetry contours overlaid on sidescan sonar mosaic)
    GIF
  4. Does the data set describe conditions during a particular time period?
    Beginning_Date: 02-May-1994
    Ending_Date: 08-May-1994
    Currentness_Reference:
    Ground Condition
  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):
      • Complete chain (136)
    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 .00002. Longitudes are given to the nearest .00002. Latitude and longitude values are specified in Decimal degrees. The horizontal datum used is North American Datum of 1983.
      The ellipsoid used is GRS80.
      The semi-major axis of the ellipsoid used is 6378137.0.
      The flattening of the ellipsoid used is 1/298.257222101.
      Vertical_Coordinate_System_Definition:
      Depth_System_Definition:
      Depth_Datum_Name: Mean low water
      Depth_Resolution: .25
      Depth_Distance_Units: Meters
      Depth_Encoding_Method: Attribute values
  7. How does the data set describe geographic features?
    onemeter.dbf
    Shapefile Attribute Table (Source: None)
    Depth
    Depth, in decimeters, of bathymetry contour interval. (Source: User Defined)
    Range of values
    Minimum:40
    Maximum:120
    Interval
    a text string to identify the contour internval. Because depth values are in decimeters this field was added to allow labeling of contour lines with a proper label. For example, the interval value for contour line with a depth 60 is -6.0 (Source: User Defined) Character field

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
    • Dave Twichell
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
    U. S. Geological Survey
    Attn: Dave Twichell
    Oceanographer
    384 Woods Hole Road
    Woods Hole, MA
    USA

    (508) 548-8700 x2266 (voice)
    (508) 457-2310 (FAX)
    dtwichell@usgs.gov

Why was the data set created?

This GIS overlay is a component of the Sarasota, Florida ArcView GIS database and contains the computer generated one meter bathymetry contours for the Sarasota study area.

How was the data set created?

  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
    Date: Unknown (process 1 of 2)
    Depth measurements were collected along the ship's track and corrected for tide changes. Because the survey area was in a shallow area off shore of Sarasota, the depth ranges were approximately 3m to 12m. The depth values were recorded in decimeters (i.e a value of 85 equals 8.5m) to provide some additional accuracy and still keep the values within an 8-bit data range. The depth information was imported into PCI Remote Sensing software and a n 8-bit image was created. That data (image) was gridded to create a seafloor surface image and 1m contours were drawn through the image using the PCI Xpace program CONTOUR. Person who carried out this activity:
    Dave Twichell
    U.S. Geological Survey
    Oceanographer
    384 Woods Hole Road
    Woods Hole, MA
    USA

    (508) 548-8700 x2266 (voice)
    (508) 457-2310 (FAX)
    dtwichell@usgs.gov
    Data sources produced in this process:
    • 1m Sarasota bathymetry contours
    Date: 12-Aug-2025 (process 2 of 2)
    This metadata file was edited for inclusion in the CMHRP metadata inventory. These edits included but are not limited to converting the metadata from HTML to XML format; fixing the publication date; added additional information in the identification section such as adding the series information, larger work ctation as well as the online links. Added the field activity number and link to the supplemental information; added the ISO 19115 Topic Category and USGS Thesaurus and appropriate terms; added the full URL to the browse graphic; specified that the information was not available freom the original metadata in some of the fields; updated the distribution liability with an FSP approved statement; added the online digital transfer option and links; updated the metadata date; provided a generic email and contact instructions in the metadata contact section; fixed all errors. Although no horizontal spatial reference information was provided in the metadata, the spatial reference was added assuming it was the same as the other related geographic coordinate system datasets in ths report, assuming the NAD83 datum with the corrected GRS80 ellipsoid. The original metadata in other files specified the North American Datum of 1983 for the horizontal datum, with the ellipsoid being WGS84. This is not possible. So the ellipsoid was modified to the GRS80 ellipsoid and associated values which is in alignment with a NAD83 datum. A persistent identifier (PID) was added to the metadata in the thesaurus section. (20250812) Person who carried out this activity:
    U.S. Geological Survey
    Attn: VeeAnn A. Cross
    Marine Geologist
    384 Woods Hole Rd.
    Woods Hole, MA
    USA

    (508) 548-8700 x2251 (voice)
    (508) 457-2310 (FAX)
    vatnipp@usgs.gov
  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?
    No information was available in the original metadata.
  3. How accurate are the heights or depths?
    No information was available in the original metadata.
  4. Where are the gaps in the data? What is missing?
    No information available from the original metadata.
  5. How consistent are the relationships among the observations, including topology?
    No information available from the original metadata.

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 The U.S. Geological Survey must be referenced as the originator of the dataset in any future products or research derived from these data.
  1. Who distributes the data set? (Distributor 1 of 1)
    U. S. Geological Survey
    Attn: Dave Twichell
    Oceanographer
    384 Woods Hole Road
    Woods Hole, MA
    USA

    (508) 548-8700 x2266 (voice)
    (508) 457-2310 (FAX)
    dtwichell@usgs.gov
  2. What's the catalog number I need to order this data set? one meter bathymetry contours of Sarasota, FL study rea
  3. What legal disclaimers am I supposed to read?
    Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty.
  4. How can I download or order the data?
  5. What hardware or software do I need in order to use the data set?
    Bathymetry contours are available in three 1- ArcView shapefile; 2 - ARC export; 3- ASCII text format. The user must have ESRI's ArcView or ARC program or another GIS application package capable of importing those data formats. The ASCII format can be read by any text editor.

Who wrote the metadata?

Dates:
Last modified: 12-Aug-2025
Metadata author:
U. S. Geological Survey
Attn: Valerie Paskevich
Computer Specialist
384 Woods Hole Rd.
Woods Hole, MA
USA

(508) 548-8700 x2281 (voice)
(508) 457-2310 (FAX)
whsc_data_contact@usgs.gov
Contact_Instructions:
The metadata contact email address is a generic address in the event the metadata contact is no longer with the U.S. Geological Survey.
Metadata standard:
FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)
This page is <https://cmgds.marine.usgs.gov/catalog/whcmsc/open_file_report/ofr1999-396/onem_meta.faq.html>
Generated by mp version 2.9.51 on Tue Aug 12 17:03:17 2025