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Not all publications have extents, not all extents are completely accurate
Approximate ground-water-level contours, April 1981, for the Soquel-Aptos area, Santa Cruz County, California
Richard M. Bloyd
1981, Open-File Report 81-680
Ground-water levels in selected wells were measured in the Soquel-Aptos, Calif., area in April 1981. On the basis of these measurements approximate ground-water-level contours were constructed. The general direction of ground-water movement in the Soquell-Aptos area is from the ridges in the northern part of the area, toward the adjacent...
Annual report of the USGS Mission, Kingdom of Saudi Arabia, for the third year of the fifth extension of the USGS-MPMR work agreement : fiscal year 1400/01, 1 Rajab 1400-30 Jumad Thani 1401 (15 May 1980-4 May 1981)
U.S. Geological Survey Saudi Arabia Mission, Saudi Arabia. Mudīrīyah al-ʻĀmmah lil-Tharwah al-Maʻdinīyah
1981, Report
An interagency report prepared by the U.S. Geological Survey Saudi Arabian Mission for the Ministry of Petroleum and Mineral Resources, Kingdom of Saudi Arabia. The work on which this report was based was performed in accordance with a cooperative agreement between the U.S. Geological Survey and the Ministry of Petroleum...
Anaerobic oxidation of acetylene by estuarine sediments and enrichment cultures
Charles W. Culbertson, Alexander J. B. Zehnder, Ronald S. Oremland
1981, Applied and Environmental Microbiology (41) 396-403
Acetylene disappeared from the gas phase of anaerobically incubated estuarine sediment slurries, and loss was accompanied by increased levels of carbon dioxide. Acetylene loss was inhibited by chloramphenicol, air, and autoclaving. Addition of 14C2H2 to slurries resulted in the formation of 14CO2 and the transient appearance of 14C-soluble intermediates, of which acetate was a major...
Hard mineral resources around the U.S continental margin
Frank T. Manheim, H.D. Hess
1981, Conference Paper, Proceedings of the Annual Offshore Technology Conference
The territorial waters surrounding the United States contain vast quantities of hard mineral resources. Some, such as sand and gravel in the New York Bight, Beaufort Sea, portions of southern California, and submerged lands near Hawaii are relatively well known and characterized by local need and immediate mining potential with...
Estimating usable resources from historical industry data
S.M. Cargill, D. H. Root, E. H. Bailey
1981, Economic Geology (76) 1081-1095
Historical production statistics are used to predict the quantity of remaining usable resources. The commodities considered are mercury, copper and its byproducts gold and silver, and petroleum; the production and discovery data are for the United States. The results of the study indicate that the...
Shear zone between the Inner Piedmont and Kings Mountain belts in the Carolinas
J. Wright Horton, Jr.
1981, Geology (9) 28-33
The Kings Mountain shear zone, which marks the boundary between the Inner Piedmont and Kings Mountain belts near the NC-SC state line, is a northeast-striking, steeply to moderately dipping zone of ductile mylonitic deformation and late-stage semibrittle deformation. The zone is at least 60 km long and is no more...
Chrysophyte cysts as potential environmental indicators
David P. Adam, Albert D. Mahood
1981, Geological Society of America Bulletin (92) 839-844
Many Chrysophyte algae produce morphologically distinctive, siliceous, microscopic cysts during a resting stage of their life cycles; these cysts are often preserved in sediments. Scanning electron microscopy and Nomarski optics permit much more detailed observation of these cysts than was heretofore possible. We have used an ecologic and biogeographic approach...
Holocene pollen and sediment record from the tangle lakes area, central Alaska
Thomas A. Ager, John D. Sims
1981, Palynology (5) 85-98
Pollen and sediments have been analyzed from a 5.5 meter‐length core of lacustrine sediments from Tangle Lakes, in the Gulkana Upland south of the Alaska Range (63 ° 01 ‘ 46”; N. latitude, 146° 03 ‘ 48 “ W. longitude). Radiocarbon ages indicate that the core spans the last 4700...
Estimation of depth to magnetic source using maximum entropy power spectra, with application to the Peru-Chile Trench
Richard J. Blakely
1981, Memoir of the Geological Society of America (154) 667-682
Estimations of the depth to magnetic sources using the power spectrum of magnetic anomalies generally require long magnetic profiles. The method developed here uses the maximum entropy power spectrum (MEPS) to calculate depth to source on short windows of magnetic data; resolution is thereby improved. The method operates by dividing...
Deep volcanic tremor and magma ascent mechanism under Kilauea, Hawaii
Keiiti Aki, Robert Y Koyanagi
1981, Journal of Geophysical Research B: Solid Earth (86) 7095-7109
Deep harmonic tremor originating at depths around 40 km under Kilauea was studied using records accumulated since 1962 at the Hawaii Volcano Observatory of the U.S. Geological Survey. The deep source of the tremor was determined by onset times and confirmed by the relative amplitude across the island-wide network of...
Conceptual models governing leaching behavior and their long-term predictive capability
Hans C. Claassen
1981, Nuclear and Chemical Waste Management (2) 307-313
Six models that may be used to describe the interaction of radioactive waste solids with aqueous solutions are as follows:Simple linear mass transfer;Simple parabolic mass transfer;Parabolic mass transfer with the formation of a diffusion-limiting surface layer at an arbitrary time;Initial parabolic mass transfer followed by linear mass transfer at an...
Radiometric and paleomagnetic evidence for the Emperor reversed polarity event at 0.46 ± 0.05 M.Y. in basalt lava flows from the eastern Snake River Plain, Idaho
Duane E. Champion, G. Brent Dalrymple, Mel A. Kuntz
1981, Geophysical Research Letters (8) 1055-1058
K-Ar and paleomagnetic data from cores through a sequence of basalt flows in the eastern Snake River Plain provide evidence for a brief (0.005 to 0.01 m.y.) reversal of the geomagnetic field 0.46 ± 0.05 m.y. ago. This reversed polarity event has also been found in sea-floor magnetic anomalies and...
Subdivision and regional stratigraphy of the pre-Punta Gorda rocks (lowermost cretaceous-jurassic?) in South Florida
A.V. Applegate, George O. Winston, James George Palacas
1981, Gulf Coast Association of Geological Societies Transactions (31) 447-453
In recent years several wells have been drilled in the South Florida Basin through carbonate and evaporite sequences to depths as much as 5,300 ft below the Punta Gorda Anhydrite. The deepest well penetrated igneous basement rocks to a total depth of 18, 670 ft. Correlation of anhydrite beds below...