Skip to main content
U.S. flag

An official website of the United States government

Publications

Publications from the staff of the Geology, Minerals, Energy, and Geophysics Science Center

Filter Total Items: 2482

Megalineament in southeastern Alaska marks southwest edge of Coast Range batholithic complex Megalineament in southeastern Alaska marks southwest edge of Coast Range batholithic complex

The Coast Range megalineament is a prominent, nearly continuous topographic and structural feature that extends southeastward about 550 km (330 mi) from its junction with the Chatham Strait – Lynn Canal fault at Point Sherman to Tongass Passage near the mouth of Pearse Canal where it leaves southeastern Alaska. It probably extends still further southeastward into British Columbia along...
Authors
David A. Brew, A. B. Ford

Paleomagnetic evidence for a Late Cretaceous deformation of the Great Valley Sequence, Sacramento Valley, California Paleomagnetic evidence for a Late Cretaceous deformation of the Great Valley Sequence, Sacramento Valley, California

Paleomagnetic samples from five localities within the Great Valley sequence range in age from Late Jurassic to Late Cretaceous. All samples possess normal polarity, and alternating-field demagnetization experiments show that the remanence was acquired after the sequence was folded. A mean paleomagnetic pole position determined from 17 demagnetized samples is located at 72° N., 181° E...
Authors
Edward A. Mankinen

Lithium in the McDermitt caldera, Nevada and Oregon Lithium in the McDermitt caldera, Nevada and Oregon

Anomalously high concentrations of lithium in fluviatile-lacustrine sediments near McDermitt, Nevada, may constitute a potential resource. These sediments are associated with a caldera about 45 km in diameter that is a result of volcanic activity, subsidence and sedimentation chiefly of Miocene age. The sediments originally were vitroclastic and now consist chiefly of authigenic zeolites...
Authors
Richard K. Glanzman, J. H. McCarthy, James J. Rytuba

Geomagnetic paleointensities from radiocarbon‐dated lava flows on Hawaii and the question of the Pacific nondipole low Geomagnetic paleointensities from radiocarbon‐dated lava flows on Hawaii and the question of the Pacific nondipole low

Radiocarbon ages have been published for nine basaltic lava flows on the island of Hawaii; the ages range from 2600 to somewhat older than 17,900 years B.P. By using the Thelliers' method in vacuum, geomagnetic paleointensity values were obtained from eight of the lavas; the ninth proved unsuitable. The paleointensities for the four youngest flows (2600–4600 years B.P.) yield virtual...
Authors
Robert S. Coe, Sherman Gromme, Edward A. Mankinen

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

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
Was this page helpful?