Determination of rare earth elements in geological materials by inductively coupled argon plasma/atomic emission spectrometry
J.G. Crock, F.E. Lichte
1982, Analytical Chemistry (54) 1329-1332
Inductively coupled argon plasma/optical emission spectrometery (ICAP/OES) is useful as a simultaneous, multielement analytical technique for the determination of trace elements in geological materials. A method for the determination of trace-level rare earth elements (REE) in geological materials using an ICAP 63-channel emission spectrometer is described. Separation and preconcentration of...
Permafrost, heat flow, and the geothermal regime at Prudhoe Bay, Alaska
A.H. Lachenbruch, J.H. Sass, B.V. Marshall, T. H. Moses Jr.
1982, Journal of Geophysical Research Solid Earth (87) 9301-9316
Temperature measurements through permafrost in the oil field at Prudhoe Bay, Alaska, combined with laboratory measurements of the thermal conductivity of drill cuttings permit an evaluation of in situ thermal properties and an understanding of the general factors that control the geothermal regime. A sharp contrast in temperature gradient at...
Extension in the Rio Grande rift
L. Cordell
1982, Journal of Geophysical Research Solid Earth (87) 8561-8569
A positive gravity anomaly along the axis of the Rio Grande rift reflects a volume of anomalous mass added at the base of the crust and intruded into the crust. Part of this volume can be associated with vertical uplift of the crust. The remainder of this anomalous volume, plus...
Comparison of amino acid racemization geochronometry with lithostratigraphy, biostratigraphy, uranium-series coral dating, and magnetostratigraphy in the Atlantic Coastal Plain of the southeastern United States
L. McCartan, J. P. Owens, B. W. Blackwelder, Barney J. Szabo, D. F. Belknap, N. Kriausakul, R.M. Mitterer, J.F. Wehmiller
1982, Quaternary Research (18) 337-359
The results of an integrated study comprising litho- and biostratigraphic investigations, uranium-series coral dating, amino acid racemization in molluscs, and paleomagnetic measurements are compared to ascertain relative and absolute ages of Pleistocene deposits of the Atlantic Coastal Plain in North and South Carolina. Four depositional events are inferred for South...
Low-temperature formation of hydrocarbon gases in San Francisco Bay sediment (California, U.S.A.)
T.M. Vogel, R.S. Oremland, K.A. Kvenvolden
1982, Chemical Geology (37) 289-298
To understand the processes responsible for the presence of low-molecular-weight hydrocarbons (C1-C4) in anoxic environments, we studied sediments collected from an anaerobic estuarine mudflat. In these sediments methane (C1) was several orders of magnitude more abundant than all other C2-C4 hydrocarbons; the C1 (C2 + C3) ratio was ??? 13,000....
Chemical and light-stable isotope characteristics of waters from the Raft River geothermal area and environs, Cassia County, Idaho; Box Elder County, Utah
M. Nathenson, N.L. Nehring, E. G. Crosthwaite, R.S. Harmon, C. Janik, J. Borthwick
1982, Geothermics (11) 215-237
Chemical and light-stable isotope data are presented for water samples from the Raft River geothermal area and environs. On the basis of chemical character, as defined by a trilinear plot of per cent milliequivalents, and light-stable isotope data, the waters in the geothermal area can be divided into waters that...
Recommended procedures and techniques for the petrographic description of bituminous coals
E. C. T. Chao, J.A. Minkin, C.L. Thompson
1982, International Journal of Coal Geology (2) 151-179
Modern coal petrology requires rapid and precise description of great numbers of coal core or bench samples in order to acquire the information required to understand and predict vertical and lateral variation of coal quality for correlation with coal-bed thickness, depositional environment, suitability for technological uses, etc. Procedures for coal...
Estimation of earthquake source parameters by the inversion of waveform data: synthetic waveforms
S.A. Sipkin
1982, Physics of the Earth and Planetary Interiors (30) 242-259
Two methods are presented for the recovery of a time-dependent moment-tensor source from waveform data. One procedure utilizes multichannel signal-enhancement theory; in the other a multichannel vector-deconvolution approach, developed by Oldenburg (1982) and based on Backus-Gilbert inverse theory, is used. These methods have the advantage of being extremely flexible; both...
Fission-track evidence for Quaternary uplift of the Nanga Parbat region, Pakistan
P.K. Zeitler, N.M. Johnson, C. W. Naeser, R.A.K. Tahirkheli
1982, Nature (298) 255-257
The north-striking Nanga Parbat-Haramosh Massif protrudes into the northwestern Himalaya along the axis of a great syntaxis1,2 (Fig. 1), where the Hindu Kush, Karakorum, and Himalayan ranges converge. As the Indus Suture Zone3 enters this region from the east it bifurcates into two branches, encircling what may be a docked...
Map reading tools for map libraries.
G.L. Greenberg
1982, Information Bulletin, Western Association of Map Libraries (13) 290-300
Engineers, navigators and military strategists employ a broad array of mechanical devices to facilitate map use. A larger number of map users such as educators, students, tourists, journalists, historians, politicians, economists and librarians are unaware of the available variety of tools which can be used with maps to increase the...
Uranium-series disequilibrium data for tooth fragments from the fossil hominid site at Ternifine, Algeria.
Barney J. Szabo
1982, South African Journal of Science (78) 205
I report here analyses of elephant molar-tooth fragments that were submitted by the late K.P.Oakley for uranium-series dating. The tooth fragments were collected by the late C. Arambourg from Pleistocene sand in association with the hominid fossils of Ternifine Man, Algeria. Of the results reported the minimum age of over...
Carbonate porosity versus depth: A predictable relation for south Florida
J. W. Schmoker, R. B. Halley
1982, American Association of Petroleum Geologists Bulletin (66) 2561-2570
This study examines the porosity of limestones and dolomites in the South Florida basin. Porosity data are derived from borehole-gravity measurements and from suites of acoustic, neutron, and density logs. Both types of wire-line measurements sample large volumes of rock relative to petrographic methods and can be examined at vertical...
Incorporation of prior information on parameters into nonlinear regression groundwater flow models: 1. Theory
Richard L. Cooley
1982, Water Resources Research (18) 965-976
Prior information on the parameters of a groundwater flow model can be used to improve parameter estimates obtained from nonlinear regression solution of a modeling problem. Two scales of prior information can be available: (1) prior information having known reliability (that is, bias and random error structure) and (2) prior...
Phase relations in the system NaCl-KCl-H2O. Part I: Differential thermal analysis of the NaCl-KCl liquidas at 1 atmosphere and 500, 1000, 1500, and 2000 bars
I.-M. Chou
1982, Geochimica et Cosmochimica Acta (46) 1957-1962
A simple differential thermal analysis (DTA) technique has been developed to study phase relations of various chemical systems at elevated pressures and temperatures. The DTA system has been calibrated against known melting temperatures in the system NaCl-KCl. Isobaric sections of the liquidus in the system NaCl-KCl have been determined at...
Organic geochemistry of core samples from an ultradeep hot well (300°C, 7 km)
Leigh C. Price
1982, Chemical Geology (37) 215-228
South Texas cores of Lower Cretaceous rocks from a depth of 6400.8 to 7544.6 m at present-day temperatures of 262–296°C have high concentrations of C15+ hydrocarbons. Bitumen coefficients range from 105 to 367 mg/g and C15+ extractable bitumen ranges from 500 to 2200 ppm. Some generation potential remains associated with the...
Differential compaction mechanism for earth fissures near Casa Grande, Arizona
R.C. Jachens, T.L. Holzer
1982, Geological Society of America Bulletin (93) 998-1012
Precise gravity measurements indicate that earth fissures or tension cracks caused by ground-water withdrawal within a 10-km2 area southeast of Casa Grande, Arizona, are associated with relief on the buried interface between the alluvial aquifer and underlying bedrock. All of the fissure zones; which...
Earthquakes of Loihi submarine volcano and the Hawaiian hot spot
F. W. Klein
1982, Journal of Geophysical Research Solid Earth (87) 7719-7726
Loihi is an active submarine volcano located 35 km south of the island of Hawaii and may eventually grow to be the next and southernmost island in the Hawaiian chain. The Hawaiian Volcano Observatory recorded two major earthquake swarms located there in 1971–1972 and 1975 which were probably associated with...
Earthquake location in island arcs
E.R. Engdahl, J. W. Dewey, K. Fujita
1982, Physics of the Earth and Planetary Interiors (30) 145-156
A comprehensive data set of selected teleseismic P-wave arrivals and local-network P- and S-wave arrivals from large earthquakes occurring at all depths within a small section of the central Aleutians is used to examine the general problem of earthquake location in island arcs. Reference hypocenters for this special data set...
Application of automated image analysis to coal petrography
E. C. T. Chao, J.A. Minkin, C.L. Thompson
1982, International Journal of Coal Geology (2) 113-150
The coal petrologist seeks to determine the petrographic characteristics of organic and inorganic coal constituents and their lateral and vertical variations within a single coal bed or different coal beds of a particular coal field. Definitive descriptions of coal characteristics and...
Genetic implications of minor-element and Sr-isotope geochemistry of alkaline rock complexes in the Wet Mountains area, Fremont and Custer counties, Colorado
T.J. Armbrustmacher, C. E. Hedge
1982, Contributions to Mineralogy and Petrology (79) 424-435
Concentrations of Rb, Sr, and REE (rare earth elements), and Sr-isotopic ratios in rocks of the Cambrian alkaline complexes in the Wet Mountains area, Colorado, show that rocks formed as end-products of a variety of magmas generated from different source materials. The complexes generally contain a bimodal suite of cumulus...
The graphic cell method: a new look at digitizing geologic maps
J.T. Hanley
1982, Computers & Geosciences (8) 149-161
The graphic cell method is an alternative method of digitizing areal geologic information. It involves a discrete-point sampling scheme in which the computer establishes a matrix of cells over the map. Each cell and the whole cell is assigned the identity or value of the geologic information that is recognized...
Formation and interpretation of dilatant echelon cracks
D. D. Pollard, P. Segall, P.T. Delaney
1982, Geological Society of America Bulletin (93) 1291-1303
The relative displacements of the walls of many veins, joints, and dikes demonstrate that these structures are dilatant cracks. We infer that dilatant cracks propagate in a principal stress plane, normal to the maximum tensile or least compressive stress. Arrays of echelon crack...
Biostratigraphy and paleoenvironment of Miocene- Pliocene hemipelagic limestone: Kingshill Seaway, St. Croix, US Virgin Islands.
B. H. Lidz
1982, Journal of Foraminiferal Research (12) 205-233
The Kingshill Limestone and younger carbonate rocks constitute the central portion of St. Croix, forming the remains of an ancient seaway that was flanked by emergent highlands. The seaway has been filled with thick epipelagic sediments alternating with carbonate turbidites and ash falls and capped with shallow-water reefal and terrigenous...
Stream-grade variation and riparian-forest ecology along Passage Creek, Virginia
Cliff R. Hupp
1982, Bulletin of the Torrey Botanical Club (109) 488-499
Passage Creek, in northwestern Virginia, flows on relatively nonresistant shales, then cuts through a gorge underlain by resistant sandstone In the gorge, the stream gradient steepens, the size of bed material increases, a braided channel forms, and riparian-forest composition and growth form changes relative to areas outside the gorge Effects...
Late Eocene- Oligocene magnetostratigraphy and biostratigraphy at South Atlantic DSDP site 522
R.Z. Poore, L. Tauxe, S.F. Percival Jr., John L. LaBrecque
1982, Geology (10) 508-511
Upper Eocene to lowest Miocene sediments recovered at Deep Sea Drilling Project (DSDP) Site 522 in the South Atlantic Ocean allow direct calibration of magnetostratigraphy and calcareous plankton biostratigraphy. The results from Site 522 show that the Eocene/Oligocene boundary occurs in the reversed...
