USGS has also accelerated the collection and analysis of magnetic, 

 gravity, high-resolution (shallow-penetration), seismic, and other 

 geophysical data that provide additional knowledge of subsurface 

 structures and thereby aid in locating and assessing oil and gas 

 potentials. 



To improve our geomagnetic knowledge of the Atlantic margin, a 

 contract was negotiated with a private company to make a detailed 

 aeromagnetic survey of the region from the Canadian border to 

 northern Florida during early 1975. The analysis and compilation of 

 the survey results by USGS scientists is expected to provide a 

 general picture of magnetic characteristics that is more accurate and 

 more detailed than any now available. The picture, combined with 

 other results of geophysical exploration, will provide further 

 information on the depth of crystalline rocks forming the basement 

 beneath sediments of the continental shelf. 



Geophysical exploration provides structural targets, but it is only 

 a portion of the information base needed to find and assess 

 petroleum potentials. Of comparable importance are data on the 

 nature of the rocks that compose the structures. Reliable 

 stratigraphic data are obtainable only by drilling. Information of 

 this type is abundant in the central Gulf of Mexico and to a lesser 

 degree off the coast of southern California, where drilling and 

 development are underway. Drillers are required to make the data 

 available to the USGS. The lack of comparable information for 

 "frontier" areas, areas where no deep holes have been drilled, such as 

 the Atlantic Continental Shelf and the Gulf of Alaska, constitutes a 

 major handicap in assessing oil and gas potentials of these areas. 



To be of value in assessing oil potential, basinal stratigraphic data 

 need not come from the structures within the basin in which 

 exploitable deposits tend to accumulate. In 1974 a petroleum 

 industry group, with USGS participation, proposed and sponsored 

 the drilling of a"public stratigraphic test hole" in the frontier area off 

 the coast of southern Texas at a site considered unlikely for a 

 petroleum discovery on the basis of geophysical data. The data were 

 used by USGS for evaluating tracts to be leased and by companies in 

 preparing bids. Industry has since proposed the drilling of similar 

 stratigraphic test holes for other prospective frontier areas off the 

 Atlantic and Alaska coasts. 



Regulatory Activities 



The Conservation Division of USGS administers regulations that 

 govern drilling and producing operations to assure human and 

 environmental safety. In collaboration with others, USGS prepares 

 and issues OCS orders, which deal with the specific problems for 



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