Publications
Publications from the staff of the Geology, Minerals, Energy, and Geophysics Science Center
Filter Total Items: 2482
Preliminary geologic map of Tecoma and Lucin quadrangles, Box Elder County, Utah, and Elko County, Nevada Preliminary geologic map of Tecoma and Lucin quadrangles, Box Elder County, Utah, and Elko County, Nevada
No abstract available.
Authors
David M. Miller, Joel D. Schneyer
Tectonic accretion of the Klamath Mountains Tectonic accretion of the Klamath Mountains
No abstract available.
Authors
W. P. Irwin
Mid-Cretaceous radiolarians in Perapedhi Formation Mid-Cretaceous radiolarians in Perapedhi Formation
No abstract available.
Authors
W. P. Irwin, B.L. Murchey, D. L. Jones, S.A. Kling
A geologic reconnaissance of the Cycladic blueschist belt, Greece A geologic reconnaissance of the Cycladic blueschist belt, Greece
The Cycladic blueschist belt consists of two distinctive segments separated by a broad zone of superposed granitic and high-temperature metamorphic rocks. The northern segment contains early metamorphic fold axes and parallel glaucophane lineations that trend ∼060° with a progressive increase in metamorphism toward the southeast. The southern segment contains similar fold axes and...
Authors
M. Clark Blake, Michel Bonneau, Jacques Geyssant, J.R. Kienast, Claude Lepvrier, Henri Maluski, Dimitrios Papanikolaou
Geology of a subduction complex in the Franciscan assemblage of northern California Geology of a subduction complex in the Franciscan assemblage of northern California
No abstract available.
Authors
M. Clark Blake, A. S. Jayko, D. G. Howell
In the southwest: Tectonic evolution reviewed In the southwest: Tectonic evolution reviewed
No abstract available.
Authors
D. M. Miller, Keith A. Howard, M. D. Carr
Seismic zonation in the San Francisco Bay region Seismic zonation in the San Francisco Bay region
No abstract available.
Authors
E. E. Brabb
Geologic transect of the northern Diablo Range, California Geologic transect of the northern Diablo Range, California
No abstract available.
Authors
M. Clark Blake
Proterozoic zircon from augen gneiss, Yukon-Tanana Upland, east-central Alaska Proterozoic zircon from augen gneiss, Yukon-Tanana Upland, east-central Alaska
U-Th-Pb analyses of zircons from an ortho-augen gneiss body in the Yukon-Tanana Upland of east-central Alaska yield strong evidence for the presence of early Proterozoic material in this area. U-Pb data define a chord that intersects concordia at about 2,300 and 345 m.y. We consider two interpretations: (1) the protolith was intruded during the Proterozoic and was subsequently...
Authors
John N. Aleinikoff, Cynthia Dusel-Bacon, Helen L. Foster, Kiyoto Futa
Geologic setting, petrology, and geochemistry of zoned tungsten-bearing skarns at the Strawberry Mine, central Sierra Nevada, California Geologic setting, petrology, and geochemistry of zoned tungsten-bearing skarns at the Strawberry Mine, central Sierra Nevada, California
The Strawberry mine, 90 km northeast of Fresno, California, occurs on the margin of a small roof pendant of Early Jurassic metasedimentary rocks and middle Cretaceous metaigneous rocks. Middle Cretaceous granitic intrusions surround and intrude the roof pendant. Adjacent to one granodiorite intrusion, several subvertical marble layers are replaced by scheelite-bearing skarns. The skarns...
Authors
Warren J. Nokleberg
Petrographic and chemical characteristics of pyrite-marcasite mineralization in hole 465A, southern Hess Rise Petrographic and chemical characteristics of pyrite-marcasite mineralization in hole 465A, southern Hess Rise
Core recovered from Hess Rise contains concentrations of pyrite, marcasite, and barite in the lowermost meter of limestone (Unit II) and in the brecciated upper part of the underlying volcanic basement (Unit HI). Petrographic and chemical data indicate that the sulfide-barite assemblage in the limestone is mainly a product of low-temperature diagenetic processes. The iron-sulfide phases...
Authors
Randolph A. Koski, James R. Hein