Since 1975, an extensive program funded primarily by the U.S. Department of Interior's Bureau of Land Management has been carried out by various government, academic, and private research organizations to evaluate the potential impact of drilling and hydrocarbon exploitation on the continental margins of the United States. The study programs were developed in response to Federal statutes, such as the Outer Continental Shelf Lands Act of 1953 (OCSLA) and its 1978 amendments, the National Environmental Policy Act (NEPA), and the Clean Water Act, and to provide new data for environmental impact statements.
The U.S. Geological Survey began geologic environmental studies programs in 1973. As leasing became imminent on the Atlantic margin, the survey developed a Memorandum of Understanding with the Bureau of Land Management in 1975 to evaluate geologic hazards on the margin that might cause or distribute oil spills, and/or of other pollutants associated with drilling operations. Additional studies funded by the bureau were conducted in cooperation with private companies and academic institutions through contracts. The problems investigated include such phenomena as sandwave movement; surface sediment transport; effects of tides, waves, and residual circulation on sediment mobility; geotechnical properties of sediments; gas in sediments; slope stability and mass wasting processes; faulting; and distribution of trace metals and hydrocarbons. As a result of such studies, potential hazards or constraints can be known prior to drilling operations, and may be reduced by proper engineering or rig siting. However, at the beginning of these studies, few data were available on the Atlantic margin to document the magnitude, location, and variability of stresses—geologic and oceanographic—that might be encountered, nor were there many measurements of the levels of various contaminants such as trace metals and hydrocarbons.
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The Atlantic Continental Margin
This synthesis covers stratigraphy, depositional processes, and geophysical interpretation of the major onshore and offshore marginal basins from Maine to the Bahamas, and includes an up-to-date review of thinking on regional tectonic history. Additional chapters discuss the theoretical aspects of thermal evolution, subsidence, and seismic stratigraphy as applied to this region. Geological resources including petroleum, water, sand and gravel, hard minerals, and heat flow are reviewed, and environmental hazards such as seismicity, coastal erosion, waste disposal and submarine instability as it relates to site of drilling platforms and mining are evaluated. A summary chapter reviews areas of controversy and suggests key topics for research.