Title
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Guyot geomorphic feature layer |
Date
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2013-06-05 |
Date type
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Creation: Date identifies when the resource was brought into existence
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Date
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2014-02-14 |
Date type
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Publication: Date identifies when the resource was issued
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Edition
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Version 1 |
Code
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e36bad09-0e62-4f92-b060-64c472382464 |
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Presentation form
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Digital map: Map represented in raster or vector form
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Abstract
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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) 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.
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Purpose
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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.
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Credit
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The global seafloor geomorphic features map has been produced through a collaboration between Geoscience Australia, GRID-Arendal
and Conservation International. Reference: Harris et. al. (2014) Geomorphology of the oceans.Marine Geology (in Press)
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Maintenance and update frequency
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Irregular: Data is updated in intervals that are uneven in duration
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Descriptive keywords
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Geology (theme). |
Descriptive keywords
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global (place). |
Descriptive keywords
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seafloor, geomorphic features, habitats (theme). |
Descriptive keywords
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Downloadable Data . |
Use limitation
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The global seafloor geomorphic feature map is available for download from bluehabitats.org |
Access constraints
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Other restrictions: Limitation not listed
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Other constraints
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no limitations |
Spatial representation type
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Vector: Vector data is used to represent geographic data
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Character set
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UTF8: 8-bit variable size UCS Transfer Format, based on ISO/IEC 10646
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Topic category code
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Oceans |
Environment description
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Microsoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; ESRI ArcGIS 10.0.4.4000 |
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