Publications
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Studies in Tertiary stratigraphy of the California Coast Ranges
The correlation of rocks of Paleogene age in California with those in Europe has had a long and complex history that can only be highlighted here. Kleinpell (1938, p. 168-181), in his classic work defining Miocene benthic1 foraminiferal stages of California, attempted to correlate faunas of California with those of western Europe and elsewhere. He pointed out that rocks usually considered lower Mi
Summary of workshops concerning regional seismic source zones of parts of the conterminous United States, convened by the U.S. Geological Survey, 1979-1980, Golden, Colorado
Workshops were convened by the U.S. Geological Survey to obtain the latest information and concepts relative to defining seismic source zones for five regions of the United States. The zones, with some modifications, have been used in preparation of new national probabilistic ground motion hazard maps by the U.S. Geological Survey. The five regions addressed are the Great Basin, the Northern Rocky
Authors
P. C. Thenhaus, F. A. McKeown, R.C. Bucknam, D. C. Ross, R.E. Anderson, W. P. Irwin, D. P. Russ, W. H. Diment
Detached crystalline rocks of the Mohave, Buck, and Bill Williams Mountains, western Arizona
No abstract available.
Authors
Keith A. Howard, J. W. Goodge, B.E. John
Regional character of mylonitic gneiss in the Cadiz Valley area, southeastern California
No abstract available.
Authors
Keith A. Howard, D. M. Miller, B.E. John
Sedimentation, metamorphism and tectonic accretion of the Franciscan assemblage of northern California
No abstract available.
Authors
M. Clark Blake, A. S. Jayko, D. G. Howell
Geologic and geochronologic reconnaissance of the Turtle Mountains area, California: West border of the Whipple Mountains detachment terrane
No abstract available.
Authors
Keith A. Howard, Paul Stone, M.A. Pernokas, R.F. Marvin
Iridium abundance measurements across the Cretaceous/Tertiary boundary in the San Juan and Raton Basins of northern New Mexico
During the past year we have been measuring trace element abundances and searching for anomalously high iridium (Ir) concentrations in continental sedimentary rocks that span the Cretaceous-Tertiary boundary in the Raton and San Juan Basins of northern New Mexico and southern Colorado. Using neutron activation and radiochemical separations, we have identified anomalous concentrations of Ir in samp
Authors
C. J. Orth, J. S. Gilmore, J.D. Knight, R.H. Tschudy, C. L. Pillmore, James E. Fassett
Geologic estimates and future costs of strip mining coal
Geologic coal-resource appraisals, which typically describe the location and general characteristics of coalbeds, do not generally provide enough information to estimate the cost of developing the resource or to predict the escalation of costs expected to result from physical depletion. This paper considers the nature of data and methods of appraisal required to provide this cost information to po
Authors
E. D. Attanasi, E.K. Green
Paleomagnetic study of some Cretaceous and Tertiary sedimentary rocks of the Klamath Mountains province, California
Paleomagnetic investigation of Cretaceous outliers and Tertiary sedimentary strata of the Klamath Mountains province, and of onlapping Cretaceous strata, has shown the rocks to be largely remagnetized. Samples studied are from the Upper Jurassic to Upper Cretaceous Great Valley sequence, Upper Cretaceous Hornbrook Formation, Eocene Montgomery Creek Formation, and Oligocene(?) Weaverville Formation
Authors
Edward A. Mankinen, William P. Irwin
Paleomagnetic data from the Coso Range, California and current status of the Cobb Mountain normal geomagnetic polarity event
Two basalt flows which erupted about 1.08 m.y. ago in the Coso Range, California, have normal magnetic polarity and thus provide additional evidence for the Cobb Mountain normal polarity event. A review of available data confirms that this event was of geomagnetic origin. A mean age of 1.10 ± 0.02 m.y. B.P. for the Cobb Mountain normal polarity event was found to best fit all available radiometric
Authors
Edward A. Mankinen, C. Sherman Grommé
Post 12 m.y. rotation of southwest Washington
Paleomagnetic field directions from the basalt of Pack Sack Lookout are compared to those from the Pomona Member of the Saddle Mountains Basalt of the Columbia River Basalt Group. The Pomona crops out over a wide region on the Columbia Plateau east of the Cascade Range, and the basalt of Pack Sack Lookout crops out well to the west of the Cascades about 30 to 60 km east of the Washington coast. Ou
Authors
James R. Magill, Ray E. Wells, Robert W. Simpson, Allan Cox
Preliminary geology of the Bristol Lake region, Mojave Desert, California
No abstract available.
Authors
D. M. Miller, Keith A. Howard, B.E. John