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Research about Delaware, Maryland, New Jersey, New York, North Carolina, South Carolina, Virginia

Source-linked reports with geographic coverage including Delaware, Maryland, New Jersey, New York, North Carolina, South Carolina, Virginia.

2 recordsLinked to original sources

U.S. Atlantic margin gas hydrates

The minimum distribution of gas hydrates on the U.S. Atlantic margin is from offshore South Carolina northward to the longitude of Shallop Canyon on the southern New England margin. Few wells have logged or sampled the gas hydrate zone on this margin, meaning that the presence of gas hydrates is inferred primarily based on seismic data that reveal bottom simulating reflections, mostly at water depths greater than 2000 m. The highest hydrate saturations most likely exist in sandy sediments of the Whale Prospect offshore New Jersey, New York, and the western part of Cape Cod, an area characterized by strong bottom simulating reflections. Such reflections are also imaged on the well-studied Blake Ridge, where fine-grained sediments host lower hydrate saturations that have been constrained by drilling. Within the section of the margin stretching from south of Cape Hatteras to nearly Hudson Canyon, the diagnostic seismic reflections are hard to discern, making inferences about gas hydrate distributions more uncertain. The recognition of as-yet unmapped bottom simulating reflections or top of gas features seaward of the 2000 m bathymetric contour (e.g., Cape Fear Slide, Currituck slide, beneath deepwater gas seeps) within the Mid-Atlantic Bight expands the area of probable gas hydrates on this margin.

Delaware, Maryland, New Jersey, New York, North Ca

Post-Hurricane Joaquin coastal oblique aerial photographs collected from the South Carolina/North Carolina border to Montauk Point, New York, October 7–9, 2015

The U.S. Geological Survey (USGS), as part of the National Assessment of Coastal Change Hazards project, conducts baseline and storm-response photography missions to document and understand the changes in vulnerability of the Nation's coasts to extreme storms (Morgan, 2009). On October 7–9, 2015, the USGS conducted an oblique aerial photographic survey of the coast from the South Carolina/North Carolina border to Montauk Point, New York (fig. 1), aboard a Cessna 182 (aircraft) at an altitude of 500 feet (ft) and approximately 1,200 ft offshore fig. 2. This mission was conducted to collect post-Hurricane Joaquin data for assessing incremental changes in the beach and nearshore area since the last surveys, mission flown in September 2014 (Virginia to New York: Morgan, 2015), November 2012 (northern North Carolina: Morgan and others, 2014) and May 2008 (southern North Carolina: unpublished report), and the data can be used to assess of future coastal change. The photographs in this report are Joint Photographic Experts Group (JPEG) images. ExifTool was used to add the following to the header of each photo: time of collection, Global Positioning System (GPS) latitude, GPS longitude, keywords, credit, artist (photographer), caption, copyright, and contact information. The photograph locations are an estimate of the position of the aircraft at the time the photograph was taken and do not indicate the location of any feature in the images (see the Navigation Data page). These photographs document the state of the barrier islands and other coastal features at the time of the survey. Pages containing thumbnail images of the photographs, referred to as contact sheets, were created in 5-minute segments of flight time. These segments can be found on the Photos and Maps page. Photographs can be opened directly with any JPEG-compatible image viewer by clicking on a thumbnail on the contact sheet. In addition to the photographs, a Google Earth Keyhole Markup Language (KML) file is provided and can be used to view the images by clicking on the marker and then clicking on either the thumbnail or the link above the thumbnail. The KML file was created using the photographic navigation files. This KML file can be found in the kml folder.

Delaware, Maryland, New Jersey, New York, North Ca