Publications
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Interim report on the St. Elias, Alaska earthquake of 28 February 1979
On 28 February 1979 an earthquake with surface wave magnitude (Ms) of 7.7 (W. Person, personal communication, 1979) occurred beneath the Chugach and St. Elias mountains of southern Alaska (fig. 1). This is a region of complex tectonics resulting from northwestward convergence between the Pacific and North American plates. To the east, the northwest-trending Fairweather fault accommodates the movem
Authors
John C. Lahr, George Plafker, C.D. Stephens, K. A. Foglean, M. E. Blackford
Multichannel seismic depth sections and interval velocities over outer continental shelf and upper continental slope between Cape Hatteras and Cape Cod: Rifted margins
Six computer-generated seismic depth sections over the outer continental shelf and upper slope reveal that subhorizontal Lower Cretaceous reflectors continue 20 to 30 km seaward of the present shelf edge. Extensive erosion on the continental slope has occurred primarily during the Tertiary, causing major unconformities and retreat of the shelf edge to its present position. The precise age and numb
Authors
John A. Grow, Robert E. Mattick, John S. Schlee
Geomagnetic paleointensities by the Thelliers' method from submarine pillow basalts: Effects of seafloor weathering
Measurements of geomagnetic paleointensity using the Thelliers' double‐heating method in vacuum have been made on 10 specimens of submarine pillow basalt obtained from 7 fragments dredged from localities 700,000 years old or younger. In the magnetic minerals, the titanium/iron ratio parameter x and the cation deficiency (oxidation) parameter x were determined by X‐ray diffraction and Curie tempera
Authors
Sherman Gromme, Edward A. Mankinen, Monte Marshall, Robert S. Coe
Landslides and related features, Pennsylvania - Pittsburgh 1° x 2° sheet
No abstract available.
Authors
John S. Pomeroy, William E. Davies
Progress on ground motion predictions for the San Francisco Bay region, California
No abstract available.
Authors
Roger D. Borcherdt, J. F. Gibbs, T. E. Fumal
Progress on seismic zonation in the San Francisco Bay region: Introduction and summary
No abstract available.
Authors
Earl E. Brabb, Roger D. Borcherdt
A large landslide on Mars
A large landslide deposit on the south wall of Gangis Chasma contains at least 100 billion m3of material that moved 60 km across the trough floor at a speed of more than 100 km/hr. The deposit consists of slump blocks at the head, hummocky material farther out, and a vast apron of longitudinally ridged material extending to the toe. The landslide deposit resembles many terrestrial ones but is much
Authors
Baerbel K. Lucchitta
Estimating pore and cement volumes in thin section
Point count estimates of pore, grain and cement volumes from thin sections are inaccurate, often by more than 100 percent, even though they may be surprisingly precise (reproducibility + or - 3 percent). Errors are produced by: 1) inclusion of submicroscopic pore space within solid volume and 2) edge effects caused by grain curvature within a 30-micron thick thin section. Submicroscopic porosity m
Authors
R. B. Halley
Limestone compaction: an enigma: comment and reply
No abstract available.
Authors
S.K. Chanda, Eugene A. Shinn, Robert B. Halley, J. Harold Hudson, Barbara H. Lidz
Factors controlling heavy-mineral variations on the South Texas outer continental shelf, Gulf of Mexico
Heavy-mineral distribution on the outer continental shelf off the southern coast of Texas shows regional variability induced by provenance and local variability reflecting genetic differences in sea-floor sediments. Q-mode factor analysis showed that three suites of heavy minerals are present. The southern ancestral Rio Grande delta sediments contain a distinct opaque-pyroxene-garnet suite, wherea
Authors
R. M. Flores, G. L. Shideler
The Aleutian Basin, Bering Sea a frontier area for hydrocarbon exploration
The Aleutian Basin is the deep water (>3000 m) basin that lies north of the Aleutian Islands adjacent to the Bering Sea continental shelf. The basin, about the size of the state of Texas, is underlain by a 2-9 km-thick flat-lying sequence of mostly Cenozoic sediment and rock that includes diatomaceous silty clay interbedded with turbidities in the upper 1 km. Before 1974, geologic and geophysical
Authors
Alan K. Cooper, David W. Scholl, A.F. Marlow, Jonathan R. Childs, George D. Redden, Keith A. Kvenvolden