The Southern Alaska PCS is a basin divided into two potential 

 hydrocarbon provinces, the Gulf of Alaska to the east and the Kodiak to 

 the west. They are similar in terms of sedimentary sequence, but have 

 significantly different structural characteristics. Although most holes 

 drilled in adjacent onshore areas have proven unsuccessful along the 

 Gulf of Alaska, there was one success in 1902, the Katalla oil field, 

 which produced about 150,000 barrels of oil before being abandoned. 

 Moreover, recent seismic surveys have indicated some large scale geologic 

 structures offshore. One structure is almost as large as the Prudhoe 

 Bay formation. 



North of the Gulf of Alaska-Kodiak Provinces is the Cook Inlet area 

 consisting of an elongate topographic and structural basin. The offshore 

 Cook Inlet basin represents a seaward extension of a larger onshore 

 petroleum province, a portion of which has been explored and is in 

 production. Through December 1974, the upper Cook Inlet area had 

 produced 600 million barrels of oil and 1.6 trillion cubic feet of gas. 

 Discovered but not yet produced reserves are estimated at 500 million 

 barrels of oil and 4.4 trillion cubic feet of gas [11]. The oil from 

 upper Cook Inlet supports a small refinery at Kenai, Alaska. 



The Bering Sea PCS is a composite of several subregions north of 

 the Alaska Peninsula arch. Of the sedimentary basins occurring within 

 or close to the Bering Sea, most promising are Bristol Bay, Norton, 

 Pribilof, St. George, Zhemchum, and Navarin. 



The Chukchi Sea OCS is an area off northwestern Alaska that contains 

 two depositional areas of interest, the Hope basin--a broad structural 

 depression in the South Chukchi Sea--and the northern Chukchi Sea 

 basin--an area underlain by geologic features similar to Prudhoe Bay and 

 Naval Petroleum Reserve No. 4. 



Beaufort Sea OCS extends between Point Barrow and the U.S. /Canadian 

 border. The Cretaceous rocks beneath the shelf apparently contain 

 organic-rich shales which may have served as source rocks for the oil 

 and gas deposits found in the younger rocks onshore. 



1,2.4 Offshore Oil and Gas Resources 



Shown in Table 4 are estimates of the potential amount of undiscovered 

 oil and gas resources on the outer continental shelf. These estimates 

 were recently (1975) prepared by the U.S. Geological Survey after extensive 

 analysis of existing geological and geophysical data. The figures show 

 that beyond the Gulf of Mexico and Southern California (which already 

 possess mature offshore industries), significant hydrocarbon potentials 

 are found only in the Mid Atlantic (Baltimore Canyon Trough), the North 

 Atlantic (Georges Bank Trough), and Alaska. The greatest potential is 

 for Alaska's basins, especially those which are ice-locked most of the 

 year. High anticipated development costs, though, have so far kept 

 interest in the ice- locked basins low. 



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