Digital seafloor character data of the Gulf of Alaska from historical National Ocean Service (NOS) smooth sheets

Metadata Updated: November 12, 2020

This data release provides seafloor-characteristics point data across the Gulf of Alaska, as digitized directly from National Oceanic and Atmospheric Administration (NOAA) National Ocean Service (NOS) smooth sheets published from 1892 to 2001, and archived at the National Geophysics Data Center (NGDC). Geo-rectification and digitization methods were adapted from Zimmermann and Benson (2013). Each location includes information for the smooth sheet number (H#####), a unique site number location, latitude, longitude, collection date, seafloor notation, and the translation of the notation. Unique site numbers were assigned randomly to each notation on a smooth sheet, starting at “_0”. Examples of seafloor notations include: rk (= rock); bu C (= blue clay); hrd (= hard); fne S (= fine sand); Co (= coral) or similar codes; the full code key is given in the Department of Commerce and Department of Defense Chart 1 (2013). In some cases, a diagrammatic indication of the seafloor character is used on the smooth sheet, such as a “”. During digitization, the corresponding value given in “Chart 1” is assigned to the location; in this case, “” denotes “rk” or “rock”. Distribution of NOS seafloor-characteristics data across the Gulf of Alaska varies widely: nearer the shoreline, data are more densely distributed; on the mid and outer continental shelf, data are more sparsely spaced. The cited locations of the points were adjusted as necessary in GIS to match the location on the geo-rectified smooth sheet in GIS as projected in North American Datum of 1983. NOAA has published the companion regional bathymetric data and its derivatives and sediment characteristics data for Cook Inlet and areas of the Aleutian Islands at The project was funded through the USGS Coastal and Marine Geology Program, NOAA National Marine Fisheries Service, Alaska Fisheries Science Center, and Alaska Fisheries Science Center Interagency Agreement AKC-119 (May 2012).

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 March 14, 2017
Metadata Created Date November 12, 2020
Metadata Updated Date November 12, 2020
Reference Date(s) January 1, 2016 (publication)
Frequency Of Update notPlanned

Graphic Preview

map of sample points used to create seafloor character map

Additional Metadata

Resource Type Dataset
Metadata Date March 14, 2017
Metadata Created Date November 12, 2020
Metadata Updated Date November 12, 2020
Reference Date(s) January 1, 2016 (publication)
Responsible Party U.S. Geological Survey, Pacific Coastal and Marine Science Center (Point of Contact)
Contact Email
Access Constraints Use Constraints: USGS-authored or produced data and information are in the public domain from the U.S. Government and are freely redistributable with proper metadata and source attribution. Please recognize and acknowledge the U.S. Geological Survey as the originator(s) of the dataset and in products derived from these data. This information is not intended for navigation purposes., Access Constraints: none
Bbox East Long -134.259811
Bbox North Lat 61.135883
Bbox South Lat 56.120981
Bbox West Long -156.222581
Coupled Resource
Frequency Of Update notPlanned
Graphic Preview Description map of sample points used to create seafloor character map
Graphic Preview File
Graphic Preview Type JPEG
Harvest Object Id 7786fe04-b756-4f53-a45c-4fbe52dec2aa
Harvest Source Id 00f54869-3a43-480d-a67c-0ba115f5d739
Harvest Source Title USGS-Harvest
Licence 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 on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty.
Metadata Language
Metadata Type geospatial
Progress completed
Spatial Data Service Type
Spatial Reference System
Spatial Harvester True
Temporal Extent Begin 1892-01-01
Temporal Extent End 2001-01-01

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