Physical deposit measures and commercial potential: The case of titanium-bearing heavy-mineral deposits
E. D. Attanasi, J.H. DeYoung Jr.
1988, Mathematical Geology (20) 97-110
Physical measures of mineral deposit characteristics, such as grade and tonnage, long have been used in both subjective and analytic models to predict favorability of areas for the occurrence of mineral deposits of particular types. After a deposit has been identified, however, the explorationist must decide whether to continue data...
Stratigraphy and magnetic polarity of the high terrace remnants in the upper Ohio and Monongahela Rivers in West Virginia, Pennsylvania, and Ohio
R. B. Jacobson, D. P. Elston, John W. Heaton
1988, Quaternary Research (29) 216-232
A synthesis of previous work and new data on the stratigraphy of high terraces of the Ohio and Monongahela Rivers upstream from Parkersburg, West Virginia, indicates a correspondence between terrace histories in the ancient Teays and Pittsburgh drainage basins. Four terraces are identified in each. Sediments of the lower three...
Downslope Eulerian mean flow associated with high-frequency current fluctuations observed on the outer continental shelf and upper slope along the northeastern United States continental margin: Implications for sediment transport
B. Butman
1988, Continental Shelf Research (8) 811-840
Eulerian current measurements made 5-7 m above bottom at six stations along the United States east coast continental margin show a net downslope flow of 1-5 cm s-1. Although the scalar current speed decreases with water depth and toward the bottom, fluctuations in the cross-isobath flow were stronger and increasingly...
General two‐point method for Determining velocity in open channel
John F. Walker
1988, Journal of Hydraulic Engineering (114) 801-805
The generally accepted procedure is to average velocity measurements at 0. 2D and 0. 8D, measured vertically from the water surface,or alternatively to measure velocity at a position equal to 0. 6D, where D is the total depth of flow. In some situations, one may wish to measure at depths...
Leachate generated by an oil-and-gas brine pond site in North Dakota
E.C. Murphy, A.E. Kehew, G.H. Groenewold, W.A. Beal
1988, Groundwater (26) 31-38
Two unlined ponds were used for holding and evaporation of brines produced with oil and gas at a well site in north-central North Dakota. The brine-evaporation ponds were in use from 1959 up to the late 1970s when they were backfilled and leveled. Continued salt-water...
Characterization of humic acid fractions by C-13 nuclear magnetic resonance spectroscopy
Robert L. Wershaw, Kevin A. Thorn, D.J. Pinckney
1988, Environmental Technology Letters (9) 53-62
Soil humic acids from different environments were fractionated by adsorption chromatography on Sephadex and characterized by C‐13 nuclear magnetic resonance (NMR) spectroscopy. The C‐13 NMR spectra of the fractions consist of some sharp, well‐resolved lines and some broad bands in contrast to the spectra of the unfractionated humic acids, where...
Migration of historical earthquakes in California
C.-Y. King, Z. Ma
1988, Pure and Applied Geophysics PAGEOPH (127) 627-639
Most large earthquakes of magnitude ???6.0 in California during 1852-1987 appear to show a southeast-to-northwest tendency of epicenter migration. This finding is consistent with earlier findings of Savage (1971) for a relatively few large earthquakes along the west coast of North America, and of Wood and Allen (1973) for smaller...
Seismic imaging of extended crust with emphasis on the western United States
J. McCarthy, G. A. Thompson
1988, Geological Society of America Bulletin (100) 1361-1374
Understanding of the crust has improved dramatically following the application of seismic reflection and refraction techniques to studies of the deep crust. This is particularly true in areas where the last tectonic event was extensional, such as the Basin and Range province of the western United States and much of...
Determining baseline element composition of lichens. I. Parmelia sulcata at Theodore Roosevelt National Park, North Dakota
L. P. Gough, R. C. Severson, L. L. Jackson
1988, Water, Air, & Soil Pollution (38) 157-167
Element-concentration baselines are given for Parmelia sulcata and associated soils. Parmelia chlorochroa was found sporadically and therefore only representative concentration ranges are reported for this species. Element data include (1) for lichens; Al, As, Ba, B, Ca, Cr, Cu, Fe, Hg, Mn, Ni, P, Sr, S, Ti, V, Y, and Zn; and (2) for...
Geophysical instrumentation near Parkfield
W. H. Bakun
1988, Earthquakes & Volcanoes (USGS) (20) 60-71
The geophysical instrumentation operated by the U.S Geological Survey and others near Parkfield is designed to monitor ongoing tectonic processes that generate earthquakes and to record the strong shaking that results from larger shocks and its effects. this discussion focuses on the former objectives; the latter is discussed in the...
The USGS plan for short-term prediction of the anticipated Parkfield earthquake
W. H. Bakun
1988, Earthquakes & Volcanoes (USGS) (20) 83-86
Aside from the goal of better understanding the Parkfield earthquake cycle, it is the intention of the U.S Geological Survey to attempt to issue a warning shortly before the anticipated earthquake. Although short-term earthquake warnings are not yet generally feasible, the wealth of information available for the previous significant Parkfield...
State public policy issues involved with the Parkfield prediction experiment.
R. Andrews, J. Goltz
1988, Earthquakes & Volcanoes (USGS) (20) 87-91
The earthquake-prediction experiment at Parkfield may well be the most important such experiment currently underway worldwide. Its importance, however, extends beyond the scientific data that will be gathered and whether those data that will be gathered and whether those data can provide reliable prediction methods. Important public policy lessons are...
History of significant earthquakes in the Parkfield area
W. H. Bakun
1988, Earthquakes & Volcanoes (USGS) (20) 45-51
Seismicity on the San Andreas fault near Parkfield occurs in a tectonic section that differs markedly from neighboring sections along the San Andreas to the northwest and to the southeast. Northwest of the Parkfield section, small shocks (magnitudes of less than 4) do occur frequently, but San Andreas movement occurs...
Parkfield; the prediction....and the promise: introduction
W. H. Bakun
1988, Earthquakes & Volcanoes (USGS) (20) 41-43
Hydraulic conductivity of a sandy soil at low water content after compaction by various methods
John R. Nimmo, Katherine C. Akstin
1988, Soil Science Society of America Journal (52) 303-310
To investigate the degree to which compaction of a sandy soil influences its unsaturated hydraulic conductivity K, samples of Oakley sand (now in the Delhi series; mixed, thermic, Typic Xeropsamments) were packed to various densities and K was measured by the steady-state centrifuge method. The air-dry, machine packing was followed...
Curie temperature isotherm analysis and tectonic implications of aeromagnetic data from Nevada
R.J. Blakely
1988, Journal of Geophysical Research Solid Earth (93) 11817-11832
Estimates of the depth to the Curie temperature isotherm in Nevada are in accordance with other regional geologic and geophysical information and together can be explained in the context of present-day tectonism. A method to estimate the depth extent of magnetic sources from the statistical properties of magnetic anomalies was...
Crystallization temperatures and stable isotope compositions of Mississippi valley-type carbonates and sulfides of the Trenton Limestone, Wyandot County, Ohio
R.J. Haefner, J.J. Mancuso, J.P. Frizado, K.L. Shelton, J.M. Gregg
1988, Economic Geology (83) 1061-1069
No abstract available....
Effect of α-damage on fission-track annealing in zircon
Masao Kasuya, Charles W. Naeser
1988, International Journal of Radiation Applications and Instrumentation. Part D. Nuclear Tracks and Radiation Measurements (14) 477-480
The thermal stability of confined fission-track lengths in four zircon samples having different spontaneous track densities (i.e., different amounts of ??-damage) has been studied by one-hour isochronal annealing experiments. The thermal stability of spontaneous track lengths is independent of initial spontaneous track density. The thermal stability of induced track lengths...
Volumetric strain in relation to particle displacements for body and surface waves in a general viscoelastic half-space
R. D. Borcherdt
1988, Geophysical Journal (93) 215-228
Dilatational earth strain, associated with the radiation fields for several hundred local, regional, and teleseismic earthquakes, has been recorded over an extended bandwidth and dynamic range at four borehole sites near the San Andreas fault, CA. The general theory of linear viscoelasticity is applied to account for anelasticity of the...
Hydrogen concentrations as an indicator of the predominant terminal electron-accepting reactions in aquatic sediments
Derek R. Lovley, S. Goodwin
1988, Geochimica et Cosmochimica Acta (52) 2993-3003
Factors controlling the concentration of dissolved hydrogen gas in anaerobic sedimentary environments were investigated. Results, presented here or previously, demonstrated that, in sediments, only microorganisms catalyze the oxidation of H2 coupled to the reduction of nitrate, Mn(IV), Fe(III), sulfate, or carbon dioxide. Theoretical considerations suggested that, at steady-state conditions, H2...
Early Cretaceous paleolatitude of the Yukon-Koyukuk province, Alaska
John W. Hillhouse, C. S. Grommé
1988, Journal of Geophysical Research Solid Earth (93) 11735-11752
We report results from a paleomagnetic study of the Yukon-Koyukuk province, a key region for reconstructing the Cretaceous paleogeography of northern Alaska and northeastern Asia. The province lies between the displaced continental fragment of Arctic Alaska and the accreted terranes of southern Alaska. Although Lower Cretaceous volcanogenic rocks of the...
Avian cholera and related topics: an annotated bibliography
Daniel M. Mulcahy, Patrick Warpinski, Linda Benjamin, D. Hamilton
1988, Biological Report 88(40)
No abstract available....
Teleseismic and near-field analysis of the Nahanni earthquakes in the Northwest Territories, Canada
G. L. Choy, J. Boatwright
1988, Bulletin of the Seismological Society of America (78) 1627-1652
The analysis of the Nahanni earthquakes of October 5, 1985 (MS 6.6), and December 23, 1985 (MS 6.9), will have important implications for the assessment of seismic hazards in intraplate environments. To maximize the information available to seismic engineers, broadband data recorded teleseismically are analyzed jointly with strong-motion data recorded...
Submarine topography of northeastern Papua New Guinea
Thomas E. Chase, Barbara A. Seekins, J. D. Young, Shawn V. Dadisman
1988, Book chapter, Geology and offshore resources of Pacific Island Arcs: New Ireland and Manus region, Papua New Guinea
No abstract available...
U.S. Geological Survey deep seismic reflection profile across the Gulf of Maine
Deborah R. Hutchinson, Kim D. Klitgord, Myung W. Lee, Anne M. Trehu
1988, Geological Society of America Bulletin (100) 172-184
Deep seismic reflection and magnetic data suggest that the Gulf of Maine is underlain by four crustal blocks of differing reflection and magnetic character. Two of these blocks, the Gulf of Maine fault zone and adjacent central plutonic zone, can be correlated with Avalonian rocks in southern New England and...
