The coring penetrated as much as 310 meters below the sea floor at 19 sites along the continental margin from Georgia to Georges Bank off New England in water depths ranging from 20 to 300 meters; 1,020 meters of material were recovered in 380 cores, ranging in age from Late Cretaceous to Holocene.
One of the major findings of the program was the discovery of relatively fresh water (salinities less than 3 parts per thousand) extending beneath the Continental Shelf as much as 60 nautical miles seaward from the New Jersey coast. Water of about 1 part per thousand salinity was found beneath the shelf more than 7 nautical miles off Ocean City, Maryland and Barnegat Inlet, New Jersey.
Analyses for light hydrocarbons in the cores show the highest concentrations (as much as 412,000 ppm) at sites in water depth greater than 200 meters ( the shelf-slope break), principally in Pleistocene sediments, although methane concentrations greater than 400,000 ppm were also found in Miocene sediments at one site near the shelf edge.
The purpose of the program was to obtain reliable data for appraisals of environmental conditions and offshore resources. Objectives included measuring geotechnical and engineering properties of the shelf sediments, defining freshwater aquifers offshore, and collecting information on possible resources such as phosphates, sand and gravel deposits, and calibrating existing geophysical data. Additional information was sought on the regional extent of geologic units, the stratigraphic column, characteristics and ages of the sediments, variance of the geochemical baseline, and zones of slope stability or potential instability.
The work was carried out aboard D/V GLOMAR CONCEPTION with the assistance of the M/V L'OLONNOIS in making seismic site surveys, anchoring the drilling vessel, and transporting supplies and equipment.
Holes were cored at 19 sites shown on the accompanying map in water depths ranging from 20 to 300 meters; 1,020 meters of material were recovered in 380 cores. A twentieth site (6003) was investigated but no cores were recovered owing to a resistant layer at the seafloor. An attempt was also made to investigate a site at latitude 32°00.99'N longitude 79°01.37'W at the inner edge of the Blake Plateau in 445 meters (1,460 feet) water depth. Anchoring was successful but the Gulf Stream prevented any attempt to drill. The current of 3 knots or greater shook the drill string to the extent drilling could not be started.
The following dbSEABED themes and fields were used for grain size analyses: SFS data: Site Name;Latitude [dec]; Longitude [dec]; Water Depth [m] #;Sampling Device;Sampler Penetration [m]; Site Date
TXR data: Top [m]; Bot [m]; Gravel [%]; Sand [%]; Silt [%] ; Clay [%]; Median Grainsize [phi]; MOMENT Mean Grainsize [phi]; MOMENT Standard Deviation [phi]; Mode/s (phiM1 [%] ...); MOMENT Skewness [phi]; MOMENT Kurtosis [phi]
GRZ data: Top (m);Bot (m);Coarse Grainsize Limit (phi);Fine Grainsize Limit (phi);Abundance of Fraction (%)
The following dbSEABED themes and fields were used for lithological descriptions: SFS data: Site Name;Latitude (deg);Longitude (deg);Water Depth (m);Core Penetration (m);Site Date;Province;Operator
LTH data: Top (m);Bot (m);Field Lithology Description;Field Consolidation Description;Field Texture Description;Mesoscale Structure;Geological Age;Colour Description;Sorting;Free Form Lithology Description
OCE data: Salinity (ppt) ppt
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