Publications
Publications from the staff of the Geology, Minerals, Energy, and Geophysics Science Center
Filter Total Items: 2354
Geochemistry and tectonic setting of some volcanic rocks of the Franklinian assemblage, central and eastern Brooks Range
No abstract available.
Authors
Thomas E. Moore
Unconformity between Coast Range ophiolite and part of the lower Great Valley sequence, South Fork of Elder Creek, Tehama County, California
The South Fork of Elder Creek is located on private property about 6 mi (10 km) northwest of Paskenta, Calif. (Fig. 1). To visit this locality it is necessary to call Mr. Les Sutfin (916-824-4628) and arrange to pick up the key to the gate at his home in Corning. From the Paskenta Store, drive 3.3 mi (5.3 km) north on the Toomes Camp road to the locked gate on the north side of the road. From here
Authors
M. C. Blake, Jr., A. S. Jayko, D. L. Jones, B. W. Rogers
Petrology and K-Ar ages of the Misheguk igneous sequence, an allochthonous mafic and ultramafic complex, and its metamorphic aureole, western Brooks Range, Alaska
No abstract available.
Authors
J.M. Boak, D. L. Turner, D.J. Henry, Thomas E. Moore, W. K. Wallace
Selenium adsorption by goethite
The adsorption of Se by goethite was studied as a function of time (10 min–24 h), temperature (295.5 and 303.5 K), pH (4–11), particle concentration (3–300 mg/L), total Se concentration (0.02–5 × 10−5 M), oxidation state [Se(IV) and Se(VI)], and competing anion concentration [(anion)/(Se(IV) = 0.25 to 50 000] in order to assess the influence of these factors on Se mobility. The data indicate that
Authors
Laurie S. Balistrieri, T. T. Chao
The stable isotopic composition of a phosphorite deposit: δ13C, δ34S, and δ18O
The stable isotopes of carbon and sulfur in a major marine sedimentary phosphate deposit from the northwestern United States (the Phosphoria Formation of Permian age) characterize the chemical properties of the depositional environment. The δ34S and δ13C analyses suggest deposition under conditions of variable redox from a solution the acidity of which was controlled by reaction with carbonate roc
Authors
David Z. Piper, Y. Kolodny
Geologic setting, petrology, and geochemistry of stratiform sphalerite-galena- barite deposits, red dog creek and drench water creek areas, northwestern Brooks Range, Alaska-a reply
No abstract available.
Authors
Ian M. Lange, Warren J. Nokleberg
Volcanism and massive sulfide formation at a sedimented spreading center, Escanaba Trough, Gorda Ridge, northeast Pacific Ocean
Seismic‐reflection profiles over the sediment‐filled Escanaba Trough at the southern Gorda Ridge reveal a series of volcanic centers that pierce the sediment. The volcanic edifices are 3 to 6 km in diameter and are spaced at 15 to 20 km intervals along the axis of the trough. The volcanic intrusions have uplifted the sediment as much as 100 m, and in places fresh basaltic flows are exposed at the
Authors
Janet L. Morton, Mark L. Holmes, Randolph A. Koski
Sediment-yield history of a small basin in southern Utah, 1937–1976: Implications for land management and geomorphology
Alluvium deposited in a reservoir from 1937 to 1976 records the sediment-yield history of a small (2.8 km2), high-relief basin in semiarid southern Utah. Stratification in the alluvium shows that sediment was deposited in the reservoir only 21 times in 38 yr, a runoff recurrence interval of 1.8 yr. Thus, on average, the particular combination of rainfall intensity, duration, and antecedent moistur
Authors
Richard Hereford
Overview of geomagnetism and paleomagnetism, 1983–1986
Michael Fuller, author of a similar overview four years ago, concluded that “...the next quadrennium promises to be a most interesting one, with plenty to keep us busy.” The 11 review papers that follow support his prediction; research in geomagnetism and paleomagnetism indeed has flourished over the last four years. In this brief overview, I will attempt to summarize what I perceive as important
Authors
Richard J. Blakely
A transect across the Mesozoic accretionary margin of central California
No abstract available.
Authors
Carl M. Wentworth, Mark D. Zoback, Andrew Griscom, Robert C. Jachens, Walter D. Mooney
The stable isotopic composition of a phosphorite deposit: δ13C, δ34S, and δ18O
The stable isotopes of carbon and sulfur in a major marine sedimentary phosphate deposit from the northwestern United States (the Phosphoria Formation of Permian age) characterize the chemical properties of the depositional environment. The δ34S and δ13C analyses suggest deposition under conditions of variable redox from a solution the acidity of which was controlled by reaction with carbonate roc
Authors
David Z. Piper, Y. Kolodny
Lead isotopic fingerprinting of tectono-stratigraphic terranes, east-central Alaska
Common lead isotopic compositions have been determined on feldspars from meta-igneous rocks from nine tectono-stratigraphic terranes or subterranes in east-central Alaska. Most of the terranes have distinct and well-defined signatures in terms of isotopic composition; thus, most can be distinguished on conventional lead isotopic diagrams. Lead isotopic ratios provide evidence for (1) possible sour
Authors
John N. Aleinikoff, Cynthia Dusel-Bacon, Helen Laura Foster, Warren J. Nokleberg