Rare-earth element geochemistry of the island-arc volcanic rocks of Rabaul and Talasea, New Britain
Joseph G. Arth
1981, Geological Society of America Bulletin (92) 858-863
The island-arc volcanic rocks of Rabaul and Talasea, New Britain, range in composition from basalt through rhyolite. Rare-earth elements have been determined by mass-spectrometric isotope dilution in 16 samples. Chondrite-normalized rare-earth element patterns are distinct for each volcanic center, but all are relatively flat (Ce/YbE.F. = 1.1 to 3.0). Within...
Lower Eocene alluvial paleosols (Willwood Formation, Northwest Wyoming, U.S.A.) and their significance for paleoecology, paleoclimatology, and basin analysis
Thomas M. Bown, M. J. Kraus
1981, Palaeogeography, Palaeoclimatology, Palaeoecology (34) 1-30
The lower Eocene Willwood Formation of northwest Wyoming is a 700 m thick accumulation of alluvial floodplain and channel mudstones and sandstones, nearly all of which show paleopedogenic modifications. Pedogenesis of Willwood sandstones is indicated by taproot and vertebrate and invertebrate bioturbation, early local cementation by calcium carbonate, and thin...
Late Quaternary environmental history of Lake Valencia, Venezuela
J. Platt Bradbury, B. Leyden, M.R. Baker, W.M. Lewis Jr., C. Schubert, M.W. Binford, D.R. Whitehead, F.H. Weibezahn
1981, Science (214) 1299-1305
Chemical, paleontological, and mineralogical analyses of a 7.5-meter core from the middle of Lake Valencia, Venezuela, have provided information on the paleoclimatic history of this low-elevation, low-latitude site for the last 13,000 years. The data show that dry climates existed in this region from 13,000 years before present (B.P.) until...
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...
Changes in the Seismicity and Focal Mechanism of Small Earthquakes Prior to an MS 6.7 Earthquake in the Central Aleutian Island Arc
Serena Billington, E.R. Engdahl, Stephanie Price
1981, Book chapter, Earthquake prediction—Addresses, essays, lectures
On November 4 1977, a magnitude Ms 6.7 (mb 5.7) shallow-focus thrust earthquake occurred in the vicinity of the Adak seismographic network in the central Aleutian island arc. The earthquake and its aftershock sequence occurred in an area that had not experienced a similar sequence since at least...
Rectangular harmonic analysis applied to the geomagnetic field
L.R. Alldredge
1981, Journal of Geophysical Research B: Solid Earth (86) 3021-3026
Spherical harmonic analysis of the earth's magnetic field is limited in the resolution that can be obtained. This limitation is caused by inadequacies of computers and of available data sets. The fundamental wavelength in spherical harmonic analysis is the circumference of the earth. To resolve wavelengths as short as 100...
On the use of nonlinear soil models
Albert T.F. Chen
1981, Conference Paper, Proceedings: First International Conference on Recent Advances in Geochemical Earthquake Engineering and Soil Dynamics
The basic definitions of, and the differences between, currently available soil models are reviewed. These models are applied to site response analyses where two depths and two levels of base input motion are considered. Computational results are presented and compared with regard to the effects of using different soil models...
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...
Proterozoic zircon from augen gneiss, Yukon-Tanana Upland, east-central Alaska
John N. Aleinikoff, Cynthia Dusel-Bacon, Helen L. Foster, Kiyoto Futa
1981, Geology (9) 469-473
U-Th-Pb analyses of zircons from an ortho-augen gneiss body in the Yukon-Tanana Upland of east-central Alaska yield strong evidence for the presence of early Proterozoic material in this area. U-Pb data define a chord that intersects concordia at about 2,300 and 345 m.y. We consider two interpretations: (1) the protolith...
Modeling natural gas reservoirs: A simple model
Richard S. Collier, E.A. Monash
1981, Society of Petroleum Engineers journal (21) 521-526
A mathematical model is developed and tested for the production of natural gas with water encroachment and gas entrapment. The model is built on the material and volumetric balance relations, the Schilthuis water drive model, and a gas entrapment mechanism which assumes that the rate of gas entrapment is proportional...
Progradational sequences in Miocene shoreline deposits, southeastern Caliente Range, California
H. Edward Clifton
1981, Journal of Sedimentary Petrology (51) 165-184
An exceptionally well exposed marine-nonmarine transition in middle Miocene strata exists in the southeastern Caliente Range, California. About 50 individual progradational sequences form a succession that ranges in thickness from approximately 1000 m (where predominantly nonmarine) to more than 2500 m (where predominantly marine). Paleogreographic evidence in basalt flows near...
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...
Late Quaternary environmental history of Lake Valencia, Venezuela
J. Platt Bradbury, B. Leyden, M. Salgado-Labouriau, W.M. Lewis Jr., C. Schubert, M.W. Binford, D.G. Frey, D.R. Whitehead, F.H. Weibezahn
1981, Science (214) 1299-1305
Chemical, paleontological, and mineralogical analyses of a 7.5-meter core from the middle of Lake Valencia, Venezuela, have provided information on the paleoclimatic history of this low-elevation, low-latitude site for the last 13,000 years. The data show that dry climates existed in this region from 13,000 years before...
Illustrated geomorphic classification of Icelandic volcanoes
Richard S. Williams Jr., Elliot C. Morris
1981, Book chapter, Reports Of planetary geology program: 1981
In 1959, Sigurdur Thorarinsson published his first complete classification of the 13 principal types of basaltic volcanoes of Iceland (Figure 1). In 1968, Thorarinssonpublished a modification of his earlier classification scheme. Both landform classifications were based on the relationship of the type of eruptive products (lava, lava and tephra, or...
Image enhancement through film recorder response contouring
John E. Boyd
1981, Conference Paper, Proceedings Volume 0278, Electro-Optical Instrumentation for Resources Evaluation
In contrast to the traditional recording from high-altitude aircraft of Earth images directly onto film in their inherently continuous analog form, a Landsat Earth resources satellite samples the ground image brightness and records it on a digital, electronic medium. Although digitization incurs several extra steps in the reproduction of the...
Role of numerical simulation in analysis of ground-water quality problems
Leonard F. Konikow
1981, Science of the Total Environment (21) 299-312
The increasing public awareness and concern about the hazards of toxic chemicals contaminating aquifers has created an increased need for predictive capabilities to analyze ground-water contamination problems. Several digital models to simulate the movement and concentration of ground-water contaminants have been documented recently. Most simulate the transport and dispersion of...
Digital elevation data as an aid to land use and land cover classification
Alden P. Colvocoresses
1981, Pecora VII Symposium 92-93
Elevation data is generally associated with topographic maps and expressed by contours and spot elevations. However, elevation data is also essential to the proper classification of land use and land cover by remote sensing techniques. Absolute elevation governs various types of vegetative growth as does the degree and direction of...
The role of remotely sensed and other spatial data for predictive modeling: the Umatilla, Oregon example
Thomas R. Loveland, Gary E. Johnson
1981, Pecora VII Symposium 442-454
The U. S. Geological Survey's Earth Resources Observations Systems Data Center, in cooperation with the U.S. Army Corps of Engineers, Portland District, developed and tested techniques that used remotely sensed and other spatial data in predictive models to evaluate irrigation agriculture in the Umatilla River Basin of north-central Oregon....
From ecological test site to geographic information system: lessons for the 1980's
Robert H. Alexander
1981, Pecora VII Symposium 359-365
Geographic information systems were common elements in two kinds of interdisciplinary regional demonstration projects in the 1970's. Ecological test sits attempted to provide for more efficient remote-sensing data delivery for regional environmental management. Regional environmental systems analysis attempted to formally describe and model the interacting regional social and...
Recovery of cholinesterase activity in five avian species exposed to dicrotophos, an organophosphorus pesticide
W. James Fleming, Christian E. Grue
1981, Pesticide Biochemistry and Physiology (16) 129-135
The responses of brain and plasma cholinesterase (ChE) activities were examined in mallard ducks, bobwhite quail, barn owls, starlings, and common grackles given oral doses of dicrotophos, an organophosphorus insecticide. Up to an eightfold difference in response of brain ChE activity to dicrotophos was found among these species. Brain ChE...
Economics and petroleum resource appraisal: The case of the Permian basin:
Emil D. Attanasi, T.M. Garland, J.H. Wood, William D. Dietzman, J.N. Hicks
1981, Journal of Petroleum Technology (33) 603-616
Estimates of oil and gas resources typically are presented in terms of proved and undiscovered resources. This paper presents a methodology for incorporating economic considerations into resource appraisals for petroleum basins. A cost algorithm is used to calculate estimates of the costs of finding and developing undiscovered oil and gas...
Coral snake mimicry: Does it occur?
H.W. Greene, R.W. McDiarmid
1981, Science (213) 1207-1212
Field observations and experimental evidence refute previous objections to the coral snake mimicry hypothesis. Concordant color pattern variation spanning hundreds of miles and several presumed venomous models strongly suggests that several harmless or mildly venomous colubrid snakes are indeed mimics of highly venomous elapids....
Miocene benthic foraminiferal isotope records: A synthesis
S.M. Savin, R.G. Douglas, G. Keller, J.S. Killingley, L. Shaughnessy, M.A. Sommer, E. Vincent, F. Woodruff
1981, Marine Micropaleontology (6) 423-450
18O/160 and 13C/12C ratios of Miocene benthic foraminifera from a number of Atlantic, Pacific and Indian Ocean DSDP sites (71, 77B, 206, 208, 238, 279, 289, 296, 329, 357 and 366A) have been compiled. These provide a rather detailed history of Miocene deep water especially in the Pacific Ocean. Bottom-water...
Results of a modeling workshop concerning development of the Beluga coal resource in Alaska
Peter J. McNamee, Austin K. Andrews, Gregor T. Auble, Richard A. Ellison, Richard L. Johnson, David B. Hamilton, James E. Roelle
1981, Report
No abstract available....
