Publications
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Geodolite measurements of deformation near Hollister, California, 1971-1978
A 24‐station trilateration network spanning the San Andreas and Calaveras faults near Hollister, California, has been surveyed each year between 1971 and 1978, inclusive. Two moderate (ML = 5) earthquakes have occurred within the network during the interval. No convincing preseismic or coseismic anomalies associated with those earthquakes have been identified. The deformation of the network can be
Authors
James C. Savage, W. H. Prescott, Michael Lisowski, N. King
Deformation across the Salton Trough, California, 1973-1977
A trilateration network extending across the San Andreas, San Jacinto, and Elsinore faults in the vicinity of the Salton Sea, California, has been surveyed to very high precision several times in the 5‐year interval 1973–1977. The average strain across the entire network is essentially a uniaxial north‐south contraction at the rate of about 0.3 μstrain/a. There is no substantial strain perpendicul
Authors
James C. Savage, W. H. Prescott, Michael Lisowski, N. King
Comparison of Miocene provincial foraminiferal stages to coccolith zones in the California Continental Borderland
Biostratigraphic ages determined by planktic coccoliths and benthic foraminifera for the same core samples from the California Continental Borderland suggest that a significant overlap exists among provincial Miocene stages of California and that some of the benthic foraminifera commonly used to recognize these stages are time-transgressive. For example, samples assigned to the middle Miocene Disc
Authors
James K. Crouch, David Bukry
Comments on opal phytoliths and stratigraphy of Neogene silicoflagellates and coccoliths at Deep Sea Drilling Project Site 397 off northwest Africa.
No abstract available.
Authors
David Bukry
Late Jurassic Independence dike swarm in eastern California
The Independence dike swarm in eastern California, more than 250 km long, extends from the eastern Sierra Nevada and Inyo Mountains through the Argus Range, Alabama Hills, and Spangler Hills to the Garlock fault, where it is offset 64 km before continuing into the Mojave Desert. The dike swarm includes a wide variety of rock types, from lamprophyre to granite porphyry belonging to a calc-alkalic s
Authors
J.-H. Chen, James G. Moore
Regional deformation of the Sierra Nevada, California, on conjugate microfault sets
Strike slip microfaults are pervasive throughout the granitic rocks of the eastern Sierra Nevada. Offsets typically range from less than a millimeter to several tens of centimeters but exceed 100 m in some places. The spacing between microfaults varies from a few tens of centimeters to a few tens of meters throughout much of the high Sierra Nevada. Many of these microfaults are loci of slickenside
Authors
J. P. Lockwood, James G. Moore
Comment and reply on ‘Mapped offset on the right-lateral Kern Canyon fault, southern Sierra Nevada, California’: Reply
No abstract available.
Authors
James G. Moore, Edward A. du Bray
Emplacement temperatures of unsorted and unstratified deposits of volcanic rock debris as determined by paleomagnetic techniques
Unsorted and unstratified deposits of volcanic rock debris typically flank recently active stratovolcanoes. It is often difficult, using standard geologic procedures, to establish whether a particular deposit was emplaced by a pyroclastic flow, lahar, rock avalanche, or glacier. Determination of the emplacement temperatures of clasts contained in the deposit aids in discriminating among some of th
Authors
Richard P. Hoblitt, Karl S. Kellogg
Preliminary geologic map of part of the southeast quarter of the Price 1° x 2° quadrangle, Carbon, Emery, and Grand Counties, central Utah
No abstract available.
Authors
Irving Jerome Witkind, Robert G. McGimsey
Vesicularity and CO2 in mid-ocean ridge basalt
Vesicles and included CO2 are enriched in deep-sea basalts that are also enriched in light rare earth and incompatible elements. This enrichment probably results from a unique deep mantle origin of such melts but may have been modified by CO2 bubbles rising in shallow magma chambers.
Authors
James G. Moore
Origin of reverse-graded bedding in air-fall pumice, Coso Range, California
The origin of reverse grading in air-fall pyroclastic deposits has been ascribed to: (1) changing conditions at an erupting vent; (2) deposition in water; or (3) rolling of large clasts over smaller clasts on the surface of a steep slope. Structural features in a deposit of air-fall pumice lapilli in the Coso Range, California, indicate that reverse grading there formed by a fourth mechanism durin
Authors
W. A. Duffield, C. R. Bacon, G.R. Roquemore
A computer-assisted graphical method for identification and correlation of igneous rock chemistries
We have devised a computer-assisted graphical method for correlating chemical analyses in suites of related igneous rocks. The method provides a direct and empirical means of sample identification using all of the reported chemistry. In a study of basalt of the Columbia River plateau, the method has been used for (1) checking field identifications of rocks, (2) spotting analytical errors in analys
Authors
Thomas L. Wright, M.S. Hamilton