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Page 383, results 9551 - 9575

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Objective procedures for lineament enhancement and extraction
G. K. Moore, F. A. Waltz
1983, Photogrammetric Engineering and Remote Sensing (49) 641-647
A longterm research goal at EROS Data Center is to develop automated, objective procedures for lineament mapping. In support of this goal, a five-step digital convolution procedure has been used to produce directionally enhanced images, which contain few artifacts and little noise. The main limitation of this procedure is that...
Tectonics and metallogenic provinces
P. W. Guild
1983, Advances in Space Research (3) 9-16
Various theories have been advanced to explain the well-known uneven distribution of metals and ore-deposit types in space and time. Primordial differences in the mantle, preferential concentration of elements in the crust, the prevalence of ore-forming processes at certain times and (or) places, and combinations of one or several of...
Reinterpretation of the exposed record of the last two cycles of Lake Bonneville, Western United States
W. E. Scott, W.D. McCoy, R. R. Shroba, M. Rubin
1983, Quaternary Research (20) 261-285
A substantially modified history of the last two cycles of Lake Bonneville is proposed. The Bonneville lake cycle began prior to 26,000 yr B.P.; the lake reached the Bonneville shoreline about 16,000 yr B.P. Poor dating control limits our knowledge of the timing of subsequent events. Lake level was maintained...
Subdivision of the Mg-suite noritic rocks into Mg-gabbronorites and Mg-norites
O.B. James, M.K. Flohr
1983, Journal of Geophysical Research Solid Earth (88) A603-A614
Mg-suite noritic rocks can be divided into two groups, the Mg-gabbronorites and the Mg-norites. The rocks of these groups differ in ratios of high-Ca pyroxene to total pyroxene, compositions of pyroxene and plagioclase, assemblages of Ti-, Nb-, and Zr-bearing minerals, compositions of chrome spinel, bulk-rock Ti/Sm and Sc/Sm, and measured...
Late Holocene ice wedges near Fairbanks, Alaska, USA: Environmental setting and history of growth
T. D. Hamilton, T. A. Ager, S.W. Robinson
1983, Arctic and Alpine Research (15) 157-168
Test trenches excavated into muskeg near Fairbanks in 1969 exposed a polygonal network of active ice wedges. The wedges occur in peat that has accumulated since about 3500 yr BP and have grown episodically as the permafrost table fluctuated in response to fires, other local site conditions and perhaps regional...
Approximate sampling distribution of the serial correlation coefficient for small samples
Gary D. Tasker
1983, Water Resources Research (19) 579-582
The probability density function for the sample serial correlation coefficient r can be approximated byf(r) = (β(½, ½(T + 1)))−1(1 − r2)½(T− 1)(1+ c2 − 2cr)−½(T), whereβ is the Beta function, T= n− 2, c = ρ − [(1 + ρ)/(n − 3)], n is the number of observations, and ρ is the population lag one serial correlation. This distribution is derived from...
Land-use planning: One geologist's viewpoint
E-An Zen
1983, Environmental Conservation (10) 97-104
Planning for the best use of land and its resources should take fully into consideration the long-term consequences of each type of use in order to stretch out most beneficially the well-being of society in the future, and to protect the integrity of the land and its...
The 1979 Homestead Valley earthquake sequence, California: Control of aftershocks and postseismic deformation
R.S. Stein, M. Lisowski
1983, Journal of Geophysical Research Solid Earth (88) 6477-6490
The coseismic slip and geometry of the March 15, 1979, Homestead Valley, California, earthquake sequence are well constrained by precise horizontal and vertical geodetic observations and by data from a dense local seismic network. These observations indicate 0.52±0.10 m of right-lateral slip and 0.17±0.04 m of reverse slip on a...
Faulting arrested by control of ground-water withdrawal in Houston, Texas
T. Holzer, R.K. Gabrysch, E.R. Verbeek
1983, Earthquake Information Bulletin (USGS) (15) 204-209
More than 86 historically active faults with an aggregate length of 150 miles have been identified within and adjacent to the Houston, Texas, metropolitan area. Although scarps of these faults grow gradually and without causing damaging earthquakes, historical fault offset has cost millions of dollars in damage to houses and...
Laboratory investigations of steam flow in a porous medium
W.N. Herkelrath, A.F. Moench, II C. F. O’Neal C. F.
1983, Water Resources Research (19) 931-937
Experiments were carried out in the laboratory to test a theory of transient flow of pure steam in a uniform porous medium. This theory is used in modeling pressure transient behavior in vapor dominated geothermal systems. Transient, superheated steam flow experiments were run by bringing a cylinder of porous material...
Helium isotopic variations in volcanic rocks from Loihi Seamount and the Island of Hawaii
M.D. Kurz, W.J. Jenkins, S.R. Hart, David Clague
1983, Earth and Planetary Science Letters (66) 388-406
Helium isotopic ratios ranging from 20 to 32 times the atmospheric 3He 4He(RA) have been observed in a suite of 15 basaltic glasses from the Loihi Seamount. These ratios, which are up to four times higher than those of MORB glasses and more than twice those of nearby Kilauea,...
Iron disulfide minerals and the genesis of roll-type uranium deposits
R. L. Reynolds, M. B. Goldhaber
1983, Economic Geology (78) 105-120
FeS 2 minerals in host rocks for deposits that contain fossil vegetal (organic) matter differ in abundance, distribution, texture, and sulfur isotopic ratios from FeS 2 minerals in host rocks for deposits that do not contain fossil vegetal matter. In three South Texas deposits lacking such organic matter, preore FeS 2 is dominantly euhedral pyrite which...
Analysis of spurious oscillation modes for the shallow water and Navier-Stokes equations
Roy A. Walters, G. F. Carey
1983, Computers and Fluids (11) 51-68
The origin and nature of spurious oscillation modes that appear in mixed finite element methods are examined. In particular, the shallow water equations are considered and a modal analysis for the one-dimensional problem is developed. From the resulting dispersion relations we find that the spurious modes in elevation are associated...
Scoresum - A technique for displaying and evaluating multi-element geochemical information, with examples of its use in regional mineral assessment programs
M.A. Chaffee
1983, Journal of Geochemical Exploration (19) 361-381
A technique called SCORESUM was developed to display a maximum of multi-element geochemical information on a minimum number of maps for mineral assessment purposes. The technique can be done manually for a small analytical data set or can be done with a computer for a large data set. SCORESUM...
The past is the key to the future
B. R. Doe
1983, Geochimica et Cosmochimica Acta (47) 1341-1354
A new major frontier of geological research, which was initiated in the 1970's, involves predicting future geologic trends or events through study of the present and past, rather than trying to understand the past, often using what one knows about the present. Like most scientific frontiers, this one began from...
A strategy for mineral and energy resource independence
W. D. Carter
1983, Advances in Space Research (3) 223-236
Data acquired by Landsats 1, 2, and 3, are beginning to provide the information on which an improved mineral and energy resource exploration strategy can be based. Landsat 4 is expected to augment this capability with its higher resolution (30 m) and additional spectral bands in the Thematic Mapper (TM)...
Inbreeding in fish populations used for aquaculture
Harold L. Kincaid
1983, Aquaculture (33) 215-227
The theoretical causes of inbreeding depression are reviewed. Studies to measure depression at a series of inbreeding levels in rainbow trout populations using the method of inbred-outbred half-sib families are discussed. While the actual depression estimates varied widely between populations and inbreeding levels, significant levels of depression were found in...
Observations of emperor geese feeding at Nelson Lagoon, Alaska
Margaret R. Petersen
1983, The Condor (85) 367-368
Estuaries along the north side of the Alaska Peninsula provide essential habitat for most of the American population of Emperor Goose (Chen canagica) during migration (Petersen and Gill 1982). Most of the population passes through Nelson Lagoon in spring and fall, with over 40,000 birds recorded there (Gill et al...
Complexation of copper by aquatic humic substances from different environments
Diane M. McKnight, Gerald L. Feder, E. Michael Thurman, Robert L. Wershaw
1983, Science of the Total Environment (28) 65-76
The copper-complexing properties of aquatic humic substances isolated from eighteen different environments were characterized by potentiometric titration, using a cupric ion selective electrode. Potentiometric data were analyzed using FITEQL, a computer program for the determination of chemical equilibrium constants from experimental data. All the aquatic humic substances could be modelled...
Populations and habitat use of marine birds in the Semidi Islands, Alaska
Scott A. Hatch, Martha A. Hatch
1983, Murrelet (64) 39-46
About one-quarter of the resident seabirds in the Gulf of Alaska breed on the Semidi Islands. In terms of biomass, the proportion is closer to one-third. The most abundant birds are Common and Thick-billed Murres, with a combined population exceeding 1 million birds. Hundreds of thousands of Horned Puffins breed...
An isolated population of small Canada geese on Kaliktagik Island, Alaska
Scott A. Hatch, Martha A. Hatch
1983, Wildfowl (34) 130-136
Recently we discovered that a small form of the Canada Goose Branta canadensis breeds on Kaliktagik Island, one of the Semidi Islands, about 80 km south of the Alaska Peninsula near longitude 157°W (Figure 1). The unexpected occurrence of geese on this oceanic island and the possibility that they are...
Nestling growth relationships of brown-headed cowbirds and dickcissels
Scott A. Hatch
1983, The Wilson Bulletin (95) 669-671
Data on nestling growth of brood parasites and their hosts are surprisingly few in the literature, Even the Brown-headed Cowbird (Molothrus ater), whose host relations have been studied in some other respects, has not been studied in any detail from this standpoint. This is particularly regrettable because the lack of...
In situ studies of velocity in fractured crystalline rocks
Daniel Moos, Mark D. Zoback
1983, Journal of Geophysical Research Solid Earth (88) 2345-2358
A study of the effects of macroscopic fractures on P and S wave velocities has been conducted in four wells drilled in granitic rock to depths between 0.6 and 1.2 km. The effect of macroscopic fractures is to decrease both Vp and Vs and increase Vp/Vs. In wells with a relatively low density of macroscopic fractures, the in situ...