SEISMIC STUDIES ON THE ALASKAN COASTAL PLAIN.
MINNESOTA UNIV MINNEAPOLIS DEPT OF GEOLOGY AND GEOPHYSICS
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Results are presented or referenced from earlier reports for three seasons, 1961-1963, of seismic field work in the vicinity of Point Barrow, Alaska. Seismic refraction data are interpreted in terms of a shallow geologic section near Point Barrow and a crustal section based upon a 280 kilometer profile northwestward from Point Barrow. The former yields velocities of 2.5, 3.1 and 4.8 kmsec with depths to top of 0, 0.4, and 1.0 kilometers. The latter has been interpreted on the basis of three geological models all include a shallow section with thickness 10-12 kilometers and velocity 4.96 kmsec, an intermediate section with velocity 6. 1-6.6 kmsec, and a high-velocity refractor with velocity 7.56 kmsec at a depth of 28-32 kilometers. Evidence is cited to support the interpretation of the high-velocity refractor as the top of the earths mantle. Seismic noise analyses were carried out on 14 of 90 available records taken at a location 50 kilometers southwest of Point Barrow. Displacement spectra in the 2-32 cps range were computed for each of the 6 vertical geophones on a 4-km spread. Phase spectra and coherence were determined for a three-component station. Six second noise samples were used, digitized at 0.01 second intervals. Author
- Geology, Geochemistry and Mineralogy