Grid File of Historical Bathymetric Soundings for Grand Bay, Mississippi, and Surrounding Areas Derived from National Ocean Service (NOS) Hydrographic Sheets

Metadata Updated: November 12, 2020

Hydrographic sheets (H-sheets) produced by the National Ocean Service (NOS) during the 1800s provide historic sounding (water depth) measurements of coastal areas. The data can be vectorized into a geographic information system (GIS), adjusted to a modern vertical datum, and converted into a digital elevation model to provide an interpretation of the historic seafloor elevation. These data were produced to provide an estimate of historical bathymetry for the Mississippi-Alabama coastal region to aid geologic and coastal hazards studies. This data release includes georeferenced H-sheets, depth soundings, and a bathymetric grid from 1852 and 1853. The original NOS H-sheets were scanned by the National Oceanic and Atmospheric Administration (NOAA) and are available through the National Geophysical Data Center (NGDC) website ( as non-georeferenced digital raster files. U.S. Geological Survey St. Petersburg Coastal and Marine Science Center (USGS SPCMSC) staff performed the following procedures: H-sheets were georeferenced, georeferenced raster images were projected to a modern datum, and historical bathymetric sounding measurements were digitized to create a vector point shapefile. Sounding data were converted from feet (ft) to meters (m), projected to modern mean low water (MLW), and converted to the North American Vertical Datum of 1988 (NAVD88) GEOID12A using NOAA’s datum transformation software, VDatum. Please read the full metadata for details on data collection, dataset variables, and data quality.

Access & Use Information

License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Metadata Date July 28, 2020
Metadata Created Date November 12, 2020
Metadata Updated Date November 12, 2020
Reference Date(s) July 31, 2020 (publication)
Frequency Of Update asNeeded

Metadata Source

Harvested from DOI Open Data

Additional Metadata

Resource Type Dataset
Metadata Date July 28, 2020
Metadata Created Date November 12, 2020
Metadata Updated Date November 12, 2020
Reference Date(s) July 31, 2020 (publication)
Responsible Party U.S. Geological Survey Coastal and Marine Science Center (Point of Contact)
Contact Email
Access Constraints Use Constraints: The U.S. Geological Survey requests to be acknowledged as originator of the data in future products or derivative research., Access Constraints: None
Bbox East Long -88.27699432210048
Bbox North Lat 30.405060892071084
Bbox South Lat 30.19505529864416
Bbox West Long -88.51531504065298
Coupled Resource
Frequency Of Update asNeeded
Graphic Preview Description Gridded bathymetric dataset derived from NOS historical (1852 and 1853) soundings and depth contours. The final, georectified raster image is provided in tagged image file format (TIFF).
Graphic Preview File Grand_Bay_Gridded_Bathymetry.tif
Graphic Preview Type TIFF
Licence This digital publication was prepared by an agency of the United States Government. Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the display or utility of the data on any other system, nor shall the act of distribution imply any such warranty. The U.S. Geological Survey shall not be held liable for improper or incorrect use of the data described and (or) contained herein. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof.
Metadata Language
Metadata Type geospatial
Progress completed
Spatial Data Service Type
Spatial Reference System
Spatial Harvester True
Temporal Extent Begin 1852-01-01
Temporal Extent End 1853-01-01

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