Publications
Publications from the staff of the Geology, Minerals, Energy, and Geophysics Science Center
Filter Total Items: 2486
Age measurements of potassium-bearing sulfide minerals by the 40Ar/39Ar technique Age measurements of potassium-bearing sulfide minerals by the 40Ar/39Ar technique
K-Ar ages have been determined for sulfide minerals for the first time. The occurrence of adequate amounts of potassium-bearing sulfides with ideal compositions K3Fe10S14 (∼10 wt.% K) and KFe2S3 (∼16 wt.% K) in samples from a mafic alkalic diatreme at Coyote Peak, California, prompted an attempt to date these materials. K3Fe10S14, a massive mineral with conchoidal fracture, gives an age...
Authors
G.K. Czamanske, M. A. Lanphere, Richard C. Erd, M.C. Blake
Regional mineral resource assessment in Alaska, a case history Regional mineral resource assessment in Alaska, a case history
No abstract available.
Authors
Donald A. Singer, W. D. Menzie, John H. DeYoung
Preliminary geologic map of the Laurel Quadrangle, Santa Cruz and Santa Clara counties, California Preliminary geologic map of the Laurel Quadrangle, Santa Cruz and Santa Clara counties, California
No abstract available.
Authors
T. W. Dibblee, E. E. Brabb, Joseph C. Clark
Preliminary geologic maps of the Chittenden, Los Gatos, and Watsonville East quadrangles, California Preliminary geologic maps of the Chittenden, Los Gatos, and Watsonville East quadrangles, California
No abstract available.
Authors
T. W. Dibblee, Earl E. Brabb
Geological Survey research 1978 Geological Survey research 1978
This U.S. Geological Survey activities report includes a summary of 1978 fiscal year scientific and economic results accompanied by a list of geologic and hydrologic investigations in progress and a report on the status of topographic mapping. The summary of results includes: (1) Mineral and water resources, (2) Engineering geology and hydrology, (3) Regional geology, (4) Principles and...
Authors
Water Resources Division U.S. Geological Survey
Geomagnetic polarity event recorded at 1.1 m.y. B.P. on Cobb Mountain, Clear Lake volcanic field, California Geomagnetic polarity event recorded at 1.1 m.y. B.P. on Cobb Mountain, Clear Lake volcanic field, California
Paleomagnetic studies show that a normal polarity event within the Matuyama reversed polarity epoch is recorded by one of the volcanic units on Cobb Mountain in northern California. K-Ar age determinations show that this event has an age of 1.12 ± 0.02 m.y. and clearly preceded the Jaramillo normal polarity event. These data provide the first confirmation from a subaerial volcano that a...
Authors
Edward A. Mankinen, J.M. Donnelly, C. S. Grommé
By
Distribution and character of upper Mesozoic subduction complexes along the west coast of North America Distribution and character of upper Mesozoic subduction complexes along the west coast of North America
Structurally complex sequences of sedimentary, volcanic, and intrusive igneous rocks characterize a nearly continuous narrow band along the Pacific coast of North America from Baja California, Mexico to southern Alaska. They occur in two modes: (1) as complexly folded but coherent sequences of graywacke and argillite that locally exhibit blueschist-grade metamorphism, and (2) as melanges
Authors
D. L. Jones, M.C. Blake, E. H. Bailey, R. J. McLaughlin
Radiolarians from pre-Nevadan rocks of the Klamath Mountains, California and Oregon Radiolarians from pre-Nevadan rocks of the Klamath Mountains, California and Oregon
No abstract available.
Authors
W. P. Irwin, D. L. Jones, T.A. Kaplan
Review of Paleozoic rocks of the Klamath Mountains Review of Paleozoic rocks of the Klamath Mountains
No abstract available.
Authors
W. P. Irwin
Plate tectonic history of the Yolla Bolly Junction, northern California: Geological Society of America Guidebook Plate tectonic history of the Yolla Bolly Junction, northern California: Geological Society of America Guidebook
No abstract available.
Authors
M. Clark Blake, A. S. Jayko, D. L. Jones
Significance of Mesozoic radiolarians from the pre-Nevadan rocks of the southern Klamath Mountains, California Significance of Mesozoic radiolarians from the pre-Nevadan rocks of the southern Klamath Mountains, California
Ribbon cherts and siliceous tuffs of the North Fork and Rattlesnake Creek terranes of the Klamath Mountains yield Mesozoic radiolarians. Rocks of the North Fork terrane were previously considered to be of Paleozoic age and those of the Rattlesnake Creek to be of Paleozoic and Triassic age, on the basis of fossiliferous limestone bodies that are now considered to be exotic blocks. In both...
Authors
W. P. Irwin, D. L. Jones, E.A. Pessagno