{ "culture": "en-US", "name": "us_canyon", "guid": "8BF8247D-3705-4500-90A1-DF62F6970971", "catalogPath": "", "snippet": "This dataset has been created in a collaborative process between CSA Ocean Sciences Inc. (CSA) and Bureau of Ocean Energy Management (BOEM) to develop one depository of maps and information on submarine canyons of the Outer Continental Shelf (OCS) to inform future Final Programmatic Environmental Impact Statements (EIS). This dataset contains all files needed to reproduce the maps electronically, with linked shapefiles containing descriptions of size, geography, history, geology, biology, water quality, and currents summarized from best available existing data for OCS submarine canyons with references.", "description": "

This dataset was created utilizing an objective system to inventory locations and names of large submarine canyons on the United States OCS in the Atlantic, Pacific, and Arctic Oceans and the Gulf of Mexico. The objective system utilized bathymetric data for average and maximum width, length and average and maximum depth of canyons to select \u2018large\u2019 submarine canyons for inclusion in this study. For the purposes of this study, submarine canyons were defined as \u201csteep-walled, sinuous valleys with V-shaped cross sections, axes sloping outwards as continuously as river-cut land canyons and relief comparable to even the largest of land canyons\u201d. One of the challenging portions of the selection process was the identification of individual canyons. While some canyons are spatially isolated from others and visually distinctive using various bathymetric data sources, others are more difficult to distinguish individually because of their proximity and overlapping or nearly overlapping dendritic patterning, especially in their shallower extents. Fortunately, a recent paper (Harris et al. 2014[1]) provided an authoritative description of many of these major canyons and was the starting point for development of the methods used in this study to determine the canyon boundaries. However, to develop a more objective methodology for this study, the basis for choosing the boundaries was based on defensible, accepted methods. In summary, the methods included: 1) examination of bathymetric datasets across all regions; 2) utilization of a series of tools within the Esri hydrology analysis Basin toolkit to extract the approximate Harris thalweg to define stream orders from the resulting flow accumulation output; 3) association of seafloor slope with canyons by examining the bathymetric raster for its cumulative frequency distribution of the slope values in SAS (2016) using PROC UNIVARIATE to sequentially eliminate the flatter slopes; 4) establishment of buffer spatial extents utilizing the 4.6th(2 Standard Deviations [SD]) percentile to determine the steepest slopes.<\/span><\/p><\/div><\/div><\/div>", "summary": "This dataset has been created in a collaborative process between CSA Ocean Sciences Inc. (CSA) and Bureau of Ocean Energy Management (BOEM) to develop one depository of maps and information on submarine canyons of the Outer Continental Shelf (OCS) to inform future Final Programmatic Environmental Impact Statements (EIS). This dataset contains all files needed to reproduce the maps electronically, with linked shapefiles containing descriptions of size, geography, history, geology, biology, water quality, and currents summarized from best available existing data for OCS submarine canyons with references.", "title": "us_canyon", "tags": [ "Pacific Ocean", "marine canyons", "CSA", "OCS", "Atlantic Ocean", "Gulf of Mexico", "submarine canyons", "ocean seafloor", "deepwater canyons", "bathymetric analysis", "BOEM", "Outer Continental Shelf", "US", "Global Ocean", "Sea Floor" ], "type": "Feature Service", "typeKeywords": [ "ArcGIS", "ArcGIS Server", "Data", "Feature Access", "Feature Service", "providerSDS", "Service" ], "thumbnail": "thumbnail/thumbnail.png", "url": "", "extent": [ [ -129.281665482182, 22.870740660535 ], [ -61.7833639461135, 51.5778371474434 ] ], "minScale": 0, "maxScale": 1.7976931348623157E308, "spatialReference": "WGS_1984_Web_Mercator_Auxiliary_Sphere", "accessInformation": "CSA Ocean Sciences Inc. (CSA), De Leo, F.C., and Ross, S.W. 2019. Large Submarine Canyons of the United States Outer Continental Shelf Atlas dataset. U.S. Dept. of the Interior, Bureau of Ocean Energy Management, Environmental Studies Program, Washington, DC, under Contract Number 140M0119F0009.", "licenseInfo": "

The Bureau of Ocean Energy Management (BOEM) provides the data for use \"as is.\" BOEM provides this information with the understanding that it is not guaranteed to be accurate, correct or complete and conclusions drawn from such information are the responsibility of the user. While every effort has been made to ensure the accuracy, correctness and timeliness of materials presented within the limits of the current state of the art, BOEM assumes no responsibility for errors or omissions, nor as a result of the failure of the data to function on a particular system. BOEM makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty. Users are cautioned to consider carefully the provisional nature of these data and information before using them for decisions that concern personal or public safety or the conduct of business that involves substantial monetary or operational consequences. Conclusions drawn from or actions undertaken on the basis of, such data and information are the sole responsibility of the user. The maps shown here are for illustration and planning purposes only and are not suitable for site-specific decision making. The data are not suitable for navigational purposes. Information found here should not be used for making financial or any other commitments. This data was developed by the U.S. Government; no other proprietary rights may be attached to them nor may they be sold to the U.S. Government as part of any procurement of products or services. Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the Bureau of Ocean Energy Management (BOEM) as the source of this information.<\/span><\/p><\/div><\/div><\/div>", "portalUrl": "" }