Rates and possible causes of neotectonic vertical crustal movements of the emerged southeastern United States Atlantic coastal plain
T. M. Cronin
1981, Geological Society of America Bulletin (92) 812-833
Emerged Pliocene and Pleistocene shorelines and associated marine deposits were used to determine the magnitude and rate of vertical crustal movement during the past 3 m.y. in the United States Atlantic Coastal Plain of South and North Carolina. On the basis of a...
Mt. St. Helens: evidence of increased magmatic gas component
R.E. Stoiber, S.N. Williams, L.L. Malinconico Jr., D. A. Johnston, T. J. Casadevall
1981, Journal of Volcanology and Geothermal Research (11) 203-212
This paper presents measurements of SO2 flux and ash leachate chemistry from Mt. St. Helens volcano during the period May 18 to July 22 which are in contrast to similar data from before May 18. Comparison of post-18 May SO2 data with similar data from other volcanoes leads to the...
Sand waves on an epicontinental shelf: Northern Bering Sea
Michael E. Field, C. Hans Nelson, David A. Cacchione, David E. Drake
1981, Marine Geology (32) 233-258
Sand waves and current ripples occupy the crests and flanks of a series of large linear sand ridges (20 km × 5 km × 10 m high) lying in an open-marine setting in the northern Bering Sea. The sand wave area, which lies west of Seward Peninsula and southeast of...
Estimation of accumulation parameters for urban runoff quality modeling
William M. Alley, Peter E. Smith
1981, Water Resources Research (17) 1657-1664
Many recently developed watershed models utilize accumulation and washoff equations to simulate the quality of runofffrom urban impervious areas. These models often have been calibrated by trial and error and with little understanding of model sensitivity to the various parameters. Methodologies for estimating best fit values of the washoff parameters...
Geology and geochemistry of gas-charged sediment on Kodiak Shelf, Alaska
M. A. Hampton, K.A. Kvenvolden
1981, Geo-Marine Letters (1) 141-147
Methane concentrations in some sediment cores from the Kodiak Shelf and adjacent continental slope increase with depth by three or four orders of magnitude and exceed the solubility in water at ambient conditions. Acoustic anomalies in seismic-reflection records imply that methane-rich sediment is widespread. Molecular composition of hydrocarbon gases and...
The Lasky cumulative tonnage-grade relationship; a reexamination
J. H. DeYoung
1981, Economic Geology (76) 1067-1080
The need for interdisciplinary research on resource appraisal techniques was recognized by Samuel G. Lasky, a U.S. Geological Survey geologist, more than 30 years ago. His efforts to devise an appraisal technique that incorporated many attributes of mineral resources resulted in a cumulative tonnage-grade relationship that has been referred to...
On the use of the nephelometer in estuarine waters
A. Eaton, V. Grant, O. Bricker, D. Wells
1981, Estuaries (4) 379-384
A study of the problems encountered in nephelometric determinations of suspended sediment loads in the Chesapeake Bay estuary has led to development of a technique which uses nephelometer readings as a guide for sampling at vertical profiles in an estuary. This permits optimum sampling for concentration profiles and allows one...
The Piney Branch Complex: A metamorphosed fragment of the central Appalachian ophiolite in northern Virginia
Avery A. Drake Jr., Benjamin A. Morgan
1981, American Journal of Science (281) 484-508
No abstract available....
Geology of central Lake Michigan
R. J. Wood, R. A. Paull, C. A. Wolosin, R. J. Friedel
1981, American Association of Petroleum Geologists Bulletin (65) 1621-1632
The geology beneath Lake Michigan between 43°00' and 44°00' N and between 86°30' and 87°40' W is interpreted from a synthesis of 1,700 km of continuous seismic reflection profile data, bathymetry, grab samples, and onshore surface and subsurface information.The continuous seismic reflection profiles and bathymetry provided information for maps of...
Geodetic strain measurements in Washington
J.C. Savage, M. Lisowski, W.H. Prescott
1981, Journal of Geophysical Research Solid Earth (86) 4929-4940
Two new geodetic measurements of strain accumulation in the state of Washington for the interval 1972–1979 are reported. Near Seattle the average principal strain rates are 0.07 ± 0.03 μstrain/yr N 19°W and −0.13 ± 0.02 μstrain/yr N71°E, and near Richland (south central Washington) the average principal strain rates are...
1980 Water resources program in Oregon
U.S. Geological Survey
1981, Report
The Water Resources Division investigates and reports on the occurrence, quantity, quality, distribution, and movement of surface and underground water. Work of the Division is described in detail later in this report....
Earthquakes in the United States, October-December 1979
Carl W. Stover, J. H. Minsch, B.G. Reagor, P. K. Smith
1981, Circular 836-D
No abstract available....
Designation of principal water-supply aquifers in Minnesota
D. G. Adolphson, J. F. Ruhl, R. J. Wolf
1981, Water-Resources Investigations Report 81-51
Fourteen aquifers, ranging from Quaternary to Precambrian in age, have been identified as the principal sources of water to wells in Minnesota. Half the municipal population anc nearly all the rural population depend on water from these aquifers. Buried and surficial sand and gravel aquifers of Quaternary age occur in...
Simulative models for the analysis of ground-water flow in Vekol Valley, the Waterman Wash area, and the Bosque area, Maricopa and Pina Counties, Arizona
D. T. Matlock
1981, Open-File Report 82-77
Simulative ground-water flow models for Vekol Valley, the Waterman Wash area, and the Bosque area were developed for use in evaluating alternatives for developing a ground-water supply for the Ak-Chin Indian Community. The hydraulic properties of the basin-fill deposits used in the models were estimated primarily from aquifer tests made...
Audio-magnetotelluric investigation of the North End Wilderness Study Area, Cochise County, Arizona
Kevin H. Nervick, Frances M. Boler
1981, Open-File Report 81-774
No abstract available....
Aeromagnetic and radio echo ice-sounding measurements over the Dufek intrusion, Antarctica
John C. Behrendt, D.J. Drewry, E. Jankowski, M. S. Grim
1981, Journal of Geophysical Research Solid Earth (86) 3014-3020
A combined aeromagnetic and radio echo ice-sounding survey (4200 km of traverse) made in 1978 in Antarctica over the Dufek layered mafic intrusion of Jurassic age suggests a minimum area of about 50,000 km2, making it comparable in size with the Bushveld Complex of Africa. Comparisons of the magnetic and...
Flow through fractures
C. E. Neuzil, James V. Tracy
1981, Water Resources Research (17) 191-199
Flow through fractures is often idealized as flow between two parallel plates (plane Poiseuille flow). The opening or aperture between parallel plates is unambiguous and its relation to flowrate is well known. However, fractures in rock have uneven walls and a variable aperture. A model for flow in a fracture...
Map projections for satellite tracking.
J.P. Snyder
1981, Photogrammetric Engineering and Remote Sensing (47) 205-213
New map projections to be used for plotting successive satellite groundtracks show these tracks as straight lines. The map may be made conformal along any 2 parallels of latitude between the limits of latitude reached by the groundtrack, or the 'tracking limits'. If these parallels are equidistant from the Equator,...
The distribution of uranium and thorium in granitic rocks of the basin and range province, Western United States
J.M. McNeal, D. E. Lee, Hugh T. Millard Jr.
1981, Journal of Geochemical Exploration (14) 25-40
Some secondary uranium deposits are thought to have formed from uranium derived by the weathering of silicic igneous rocks such as granites, rhyolites, and tuffs. A regional geochemical survey was made to determine the distribution of uranium and thorium in granitic rocks of the Basin and Range province in order...
The Georgia Embayment continental shelf: stratigraphy of a submergence.
O. H. Pilkey, B. W. Blackwelder, H.J. Knebel, M.W. Ayers
1981, Geological Society of America Bulletin (92) 52-63
The Holocene-Pleistocene sediment veneer is thin, generally less than 4m thick. Lagoon sediments deposited during the last regression or the Holocene transgression occur in patches on the inner and central shelf. During each transgression or submergence, the surficial sand sheet is recharged with a new biogenic carbonate fraction along with...
Exsolution of Ca-clinopyroxene from orthopyroxene aided by deformation
S. H. Kirby, M.A. Etheridge
1981, Physics and Chemistry of Minerals (7) 105-109
Monoclinic calcium-poor shear-transformation lamellae and calcium-rich exsolution lamellae occur parallel to (100) in orthopyroxene. The formation of both structures from an orthopyroxene host involves a shear on (100) parallel to [001], with additional cation exchange in the exsolution case. The shear transformation involves a macroscopic simple shear angle of 13.3??...
Use of 35-mm color aerial photography to acquire mallard sex ratio data
Edgar L. Ferguson, Dennis G. Jorde, John L. Sease
1981, Photogrammetric Engineering and Remote Sensing (47) 823-827
A conventional 35-mm camera equipped with an f2.8 135-mm lens and ASA 64 color film was used to acquire sex ratio data on mallards (Anas platyrhynchos) wintering in the Platte River Valley of south-central Nebraska. Prelight focusing for a distance of 30.5 metres and setting of shutter speed at 1/2000...
Map showing water circulation and rates of sedimentation in the Corpus Christi 1 degree by 2 degrees quadrangle, Texas
H. L. Berryhill Jr., A. R. Trippet
1981, IMAP 1287-A
No abstract available....
Two oil types on North slope of Alaska: Implications for exploration
L. B. Magoon, George E. Claypool
1981, American Association of Petroleum Geologists Bulletin (65) 644-652
Forty oil samples from across the North Slope of Alaska have been analyzed by the U.S. Bureau of Mines and the U.S. Geological Survey. Results of these analyses suggest two separate genetic oil types. The first, the Simpson-Umiat oil type, occurs in reservoir rocks of Cretaceous and Quaternary age and...
Loss of nitrogenous dissolved organic matter from small lakes
Bruce A. Manny, Akira Otsuki
1981, Journal of Freshwater Ecology (1) 193-202
To determine how much organic nitrogen is lost from lakes during winter by natural processes, we collected water in fall and winter from six small lakes (area, 5-822 hectares) and separated organic matter dissolved in the water with n-butanol into three fractions--yellow organic acids, a white precipitate, and aqueous (nonextractable)...
