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Shapefile of Historical Bathymetric Soundings for Mississippi and Alabama Derived from National Ocean Service (NOS) Hydrographic Sheets

Metadata Updated: July 28, 2022

Hydrographic sheets (H-sheets) and nautical charts 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 derived from the 1847 and 1895 soundings. The original NOS H-sheets and nautical charts were scanned by the National Oceanic and Atmospheric Administration (NOAA) and are available through the National Geophysical Data Center (NGDC) website (NOAA, 2021) 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) and fathoms (fm) 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, digitized data, dataset variables, and data quality.

Access & Use Information

Public: This dataset is intended for public access and use. 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 Created Date July 28, 2022
Metadata Updated Date July 28, 2022

Metadata Source

Harvested from DOI DCAT-US harvest source

Additional Metadata

Resource Type Dataset
Metadata Created Date July 28, 2022
Metadata Updated Date July 28, 2022
Publisher U.S. Geological Survey
Unique Identifier Unknown
Identifier USGS:f7933b13-0064-40dd-8dda-41a0d3116e16
Data Last Modified 20220315
Category geospatial
Public Access Level public
Bureau Code 010:12
Metadata Context
Schema Version
Catalog Describedby
Harvest Object Id 79740e69-e263-47c1-a90b-b80f2951857d
Harvest Source Id bee011ae-6f4a-4b9b-bef9-6c8b6453c562
Harvest Source Title DOI DCAT-US harvest source
Metadata Type geospatial
Old Spatial -88.715659, 29.960964, -87.672267, 30.789348
Publisher Hierarchy Department of the Interior > U.S. Geological Survey
Source Datajson Identifier True
Source Hash b34d70d6ad00c69c9cd80e8d42684203b1ea9267
Source Schema Version 1.1
Spatial {"type": "Polygon", "coordinates": -88.715659, 29.960964, -88.715659, 30.789348, -87.672267, 30.789348, -87.672267, 29.960964, -88.715659, 29.960964}

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