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Guyot geomorphic feature layer
Resource ID
ffcb3444-dd78-11eb-9b1a-0242c0a82008
Title
Guyot geomorphic feature layer
Date
Feb. 5, 2014, midnight, Publication
Abstract
The guyot geomorphic feature layer represents the spatial extent of the guyots of the worlds oceans based on interpretation of the SRTM30 plus v7 global bathymetry model. The layer is one of the 25 layers that make up the global seafloor geomorphic features map (Harris et.al. 2014). Guyots are “an isolated (or group of) seamount (s) having a comparatively smooth flat top. Also called tablemount(s)” (IHO, 2008). In this study the seamount base layer was used to mask the SRTM30_PLUS model. The gradient of the resulting grid was calculated (ArcGIS 10->DEM Surface Tools (Jenness 2012)->Slope, Slope computation method = 4-cell method). The gradient was classified into areas >2 degrees and areas <2 degrees. The areas less than two degrees were converted into vector layers. Where these occurred at the top of seamounts and were greater than a minimum size threshold (10 km2) they were flagged as possible guyots. These possible guyots were then visually checked and either classified as a guyot or a seamount. Additionally the remaining seamounts were visually checked to see whether any with flat tops had been missed in the classification process. The geomorphic features map of Agapova et al (1979) was used in addition to the GEBCO Gazetteer of geographic names of undersea features (IHO-IOC, 2012), to ensure all previously mapped features were assessed for inclusion in our map.
Edition
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Owner
jcleary
Point of Contact
Collart
tim.collart@seascapebelgium.be
Purpose
The guyot geomorphic feature layer represents the spatial extent of the guyots of the worlds oceans based on interpretation of the SRTM30 plus v7 global bathymetry model. The layer is one of the 25 layers that make up the global seafloor geomorphic features map (Harris et.al. 2014). The global seafloor geomorphic features map is intended to support ocean management including feature inventories, spatial planning and biodiversity conservation.
Maintenance Frequency
None
Type
not filled
Restrictions
None
no limitations on public access
License
Creative Commons Attribution 4.0 International
Language
eng
Temporal Extent
Start
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End
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Supplemental Information
No information provided
Data Quality
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Extent
  • x0: -179.947219848633000
  • x1: 178.557327270508000
  • y0: -69.015853881835900
  • y1: 57.641471862793000
Spatial Reference System Identifier
EPSG:4326
Keywords
no keywords
Category
Oceans
Regions
Global