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At least 577 records · Page 32Linked to original sources
USGS1975

Hydrocarbon potential, geologic hazards, and the technology, time-frame and infrastructure for exploration and development of the lower Cook Inlet, Alaska; a preliminary assessment

The Lower Cook Inlet Outer Continental Shelf (OCS) contains 5600 km 2 of submerged land in less than 200 m of water 150 to 350 km southwest of Anchorage, Alaska. This area could contain from 0.3 to 1.4 billion barrels of oil and from 0.6 to 2.7 trillion cubic feet of natural gas depending upon the statistical confidence level indicated. The known geology of this submerged area, is extrapolated to the offshore from onshore data. The sedimentary rocks are as old as Triassic and as young as Pleistocene. The Mesozoic strata include volcanic rocks, volcanoclastic and marine clastic sediments. Tertiary, rocks from which the oil and gas in Upper Cook Inlet are produced, consist of nonmarine conglomerate, sandstone, siltstone and coal. The potential objective section for oil and gas in this OCS area ranges from Middle Jurassic through the Tertiary. The present structural configuration of this area is a northeast trending trough filled with Tertiary sediments. The trough is flanked by two major faults, the Bruin Bay fault on the northwest and the Border Ranges fault on the southeast. Between these faults is the OCS area containing anticlinal structures and faults which may be traps for hydrocarbons. Potential geologic hazards are present in this area. It is an area of intense tectonism expressed as seismic activity (earthquakes) and volcanic eruptions which produce many natural disturbances including tsunamis. This distribution of soft sediment and other submarine features which relate to geologic hazards are only generally known.

Alaska↗
USGS1976

Water and stream-sediment sampling techniques for use in uranium exploration

Methods of sampling water and stream sediments for uranium were established in this study. Water samples should be taken using a US DH-48 water sampler across the stream channel and should be filtered and acidified in situ. Stream sediments should be taken as a composite sample up and across the axis of the channel. Only sediment fractions less than 90 ?m (170 mesh) should be analyzed for uranium. The elements As, Ca, Al, B, Mg, K, and Na exhibit a positive correlation with uranium in surface waters, while a much larger suite of elements exhibit a positive correlation with uranium in stream sediments: K, Mn, Mg, Ti, Ca, Al, Fe, Pb, Cr, Y, Zr, Li, Zn, Th, and As. Analyses have revealed that anomalies detected in either the dissolved or suspended fractions of water, or the stream sediments, are frequently not reflected in the other two; hence, all three should be sampled and analyzed.

Open-File Report↗