GEOLOGIC PROCESSES AFFECTING THE QUALITY OF THE UPPER FREEPORT COAL BED, WEST-CENTRAL PENNSYLVANIA.
R.W. Stanton, C. B. Cecil, B.S. Pierce, L.F. Ruppert, F.T. Dulong
1985, Conference Paper
The number or types of origins of the components of a coal bed cannot be determined from its bulk composition. Minerals such as quartz, calcite, and pyrite as well as macerals such as vitrinite can originate from a variety of processes that result from different depositional conditions. The Upper Freeport...
An ocean bottom seismometer study of shallow seismicity near the Mid- America Trench offshore Guatemala
E. L. Ambos, D.M. Hussong, C.E. Holman
1985, Journal of Geophysical Research Solid Earth (90) 11397-11412
Five ocean bottom seismometers recorded seismicity near the Mid-America Trench offshore Guatemala for 27 days in 1979. The array was emplaced in the lower slope region, just above the topographic trench, in the area investigated during Deep Sea Drilling Project legs 67 and 84. Approximately 170 events were recorded by...
Regional setting and new information on some critical geologic features of the West Shasta district, California
J. P. Albers, J.H.C. Bain
1985, Economic Geology (80) 2072-2091
The West Shasta massive sulfide district is in the easternmost of a series of accreted island-arc and oceanic crust terranes that comprise the Klamath Mountains. A sequence of submarine volcanic rocks of predominantly Early Devonian age is the principal component of the island-arc terrane in which the sulfide deposits are...
Comparison of daily and weekly precipitation sampling efficiencies using automatic collectors
L.J. Schroder, R.A. Linthurst, J.E. Ellson, S.F. Vozzo
1985, Water, Air, & Soil Pollution (24) 177-187
Precipitation samples were collected for approximately 90 daily and 50 weekly sampling periods at Finley Farm, near Raleigh, North Carolina from August 1981 through October 1982. Ten wet-deposition samplers (AEROCHEM METRICS MODEL 301) were used; 4 samplers were operated for daily sampling, and 6 samplers were operated for weekly-sampling periods....
Demonstration of two pulses of Paleogene deformation in the Andes of Peru
D. C. Noble, M. Sebrier, F. Megard, E.H. McKee
1985, Earth and Planetary Science Letters (73) 345-349
New radiometric ages of about 25 m.y. on volcanic materials in a marine intercalation within clastic continental strata of the Upper Moquegua Formation near Caraveli, southern Peru, together with an age of25.3 ± 0.4 m.y obtained by Tosdal et al. from a...
Early Tertiary marine fossils from northern Alaska: Implications for Arctic Ocean paleogeography and faunal evolution
L. Marincovich Jr., E. M. Brouwers, L. D. Carter
1985, Geology (13) 770-773
Marine mollusks and ostracodes indicate a post-Danian Paleocene to early Eocene (Thanetian to Ypresian) age for a fauna from the Prince Creek Formation at Ocean Point, northern Alaska, that also contains genera characteristic of the Cretaceous and Neogene-Quaternary. The life-association of heterochronous taxa...
Interannual streamflow variability in the United States based on principal components
Harry F. Lins
1985, Water Resources Research (21) 691-701
Interannual modes of streamflow variation at 106 locations across the United States during the period 1931–1978 are defined by using principal components. Five statistically significant components are found to account for more than 56% of the total streamflow variance. The first principal component represents a nationwide tendency for either above-...
MARINE MINERAL RESOURCES - AN UPDATE AND INTRODUCTION.
Michael J. Cruickshank, William Siapno
1985, Marine Technology Society Journal (19) 3-5
This article briefly traces the status of marine minerals development, and it describes papers presented in this special issue on the subject. Subjects covered include types of deposits, marine mining in Canada, Manganese nodules, metalliferous sulfides as seabed minerals, metallurgical processes for reducing sulfide minerals, U. S. phosphate industry, construction...
Solubility relations in the system sodium chloride-ferrous chloride-water between 25 and 70.degree.C at 1 atm
I.-M. Chou, L.D. Phan
1985, Journal of Chemical and Engineering Data (30) 216-218
Solubility relations in the ternary system NaCl-FeCl2-H2O have been determined by the visual polythermal method at 1 atm from 20 to 85??C along six composition lines. These she composition lines are defined by mixing FeCl2??4H2O with six aqueous NaCl solutions containing 5, 10, 11, 15, 20, and 25 wt %...
Afrotarsius chatrathi, first tarsiiform primate (? Tarsiidae) from Africa
E.L. Simons, T. M. Bown
1985, Nature (313) 475-477
Tarsiiform primates have long been regarded as a Laurasian group, with an extensive fossil record in the Eocene of North America and Europe1-4 and two important but less well-known records from Asia5,6. The only living genus is Tarsius (Tarsiidae), whereas all of the fossil tarsier-like primates are usually placed in...
The 1983 hydraulic jump in Crystal Rapid: Implications for river- running and geomorphic evolution in the Grand Canyon
S. W. Kieffer
1985, Journal of Geology (93) 385-406
At Crystal Creek, a debris fan was emplaced in 1966, constricting the channel of the Colorado River to about 0.25 of its upstream width between 1967 and 1983, forming a major rapid. The hydraulics of Crystal Creek rapid are described, and an analysis is presented to support the hypothesis that...
Anomalous 13C enrichment in modern marine organic carbon
M.A. Arthur, W.E. Dean, George E. Claypool
1985, Nature (315) 216-218
Marine organic carbon is heavier isotopically (13C enriched) than most land-plant or terrestrial organic C1. Accordingly, ??13C values of organic C in modern marine sediments are routinely interpreted in terms of the relative proportions of marine and terrestrial sources of the preserved organic matter2,3. When independent geochemical techniques are used...
Review of radiometric data from the Yukon crystalline terrane, Alaska and Yukon Territory
Frederic H. Wilson, James G. Smith, Nora B. Shew
1985, Canadian Journal of Earth Sciences (22) 525-537
The results of more than 20 years of geochronological studies in the Yukon Crystalline Terrane in east-central Alaska and the western Yukon Territory suggest at least six igneous and thermal (metamorphic?) events. Plutonism during Mississippian, Early Jurassic, mid-Cretaceous, Late Cretaceous, and early Tertiary times is indicated. Evidence also indicates that...
Origin of discontinuities in coal-bearing strata at roaring creek (basal Pennsylvanian of Indiana)
W.J. Nelson, Donald L. Eggert, William A. DiMichele, A.C. Stecyk
1985, International Journal of Coal Geology (4) 355-370
Basal Pennsylvanian coal-bearing strata exposed along Roaring Creek, west-central Indiana, exhibit extreme lateral discontinuity. Coal seams abruptly change in thickness and elevation; they split, grade into shale, are cut out by channels and disrupted by soft-sediment deformational structures. Initial sediments were...
Dissolution of barite for the analysis of strontium isotopes and other chemical and isotopic variations using aqueous sodium carbonate
G. N. Breit, E.C. Simmons, M. B. Goldhaber
1985, Chemical Geology: Isotope Geoscience Section (52) 333-336
A simple procedure for preparing barite samples for chemical and isotopic analysis is described. Sulfate ion, in barite, in the presence of high concentrations of aqueous sodium carbonate, is replaced by carbonate. This replacement forms insoluble carbonates with the cations commonly in barite: Ba, Sr, Ca and Pb. Sulfate is...
More on the alleged 1970 geomagnetic jerk
L.R. Alldredge
1985, Physics of the Earth and Planetary Interiors (39) 255-264
French and United Kingdom workers have published reports describing a sudden change in the secular acceleration, called an impulse or a jerk, which took place around 1970. They claim that this change took place in a period of a year or two and that the sources of the alleged jerk...
Upper Wisconsinan submarine end moraines off Cape Ann, Massachusetts
R. N. Oldale
1985, Quaternary Research (24) 187-196
Seismic profiles across the southwest end of Jeffreys Ledge, a bathymetric high north of Cape Ann, Massachusetts, reveal two end moraines. The moraines overlie upper Wisconsinan glacialmarine silty clay and are composed mostly of subaqueous ice-contact deposits and outwash. They were formed below sea level in water depths of as...
PREPRO: a computer program for encoding regional exploration data for use in characteristic analysis
N.J. Bridges, J.T. Hanley, R.B. McCammon
1985, Computers & Geosciences (11) 513-519
The preprocessor (PREPRO) computer program offers the exploration geologist a variety of options for encoding regional exploration data into ternary form for use in characteristic analysis. PREPRO's options include variable-input formats, cursor input, ordering among a set of input variables, and selectable ternary transformations. Moreover, the program provides for the...
Comparison of aquifer characteristics derived from local and regional aquifer tests
R.B. Randolph, R.E. Krause, M.L. Maslia
1985, Groundwater (23) 309-316
A comparison of the aquifer parameter values obtained through the analysis of a local and a regional aquifer test involving the same area in southeast Georgia is made in order to evaluate the validity of extrapolating local aquifer-test results for use in large-scale flow simulations. Time-drawdown and time-recovery data were...
Redescription of Bellerophon asiaticus Wirth (Early Triassic: Gastropoda) from China, and a survey of Triassic Bellerophontacea
E.Y. Yochelson, Hongfu Yin
1985, Journal of Paleontology (59) 1305-1319
The bilaterally symmetrical gastropod Bellerophon asiaticus Wirth is redescribed from specimens collected in Guizhou Province, PRC. The species is reassigned to Retispira, a common late Paleozoic taxon. Retispira is another example of a Paleozoic gastropod genus that crossed the era boundary. Associated pelecypods that date these Guizhou occurrences as Early...
Origin of caves and other solution openings in the unsaturated (vadose) zone of carbonate rocks: A model for CO2 generation
W.W. Wood
1985, Geology (13) 822-824
The enigma that caves and other solution openings form in carbonate rocks at great depths below land surface rather than forming from the surface downward can be explained by the generation of CO2 within the aquifer system. In the proposed model, CO2 is generated by the oxidation of particulate and/or...
Global map of eolian features on Mars
A. W. Ward, K.B. Doyle, P. J. Helm, M.K. Weisman, N.E. Witbeck
1985, Journal of Geophysical Research Solid Earth (90) 2038-2056
Ten basic categories of eolian features on Mars were identified from a survey of Mariner 9 and Viking orbiter images. The ten features mapped are (1) light streaks (including frost streaks), (2) dark streaks, (3) sand sheets or splotches, (4) barchari dunes, (5) transverse dunes, (6) crescentic dunes, (7) anomalous...
The Schwartzwalder uranium deposit, II: Age of uranium mineralization and lead isotope constraints on genesis
K.R. Ludwig, A. R. Wallace, K. R. Simmons
1985, Economic Geology (80) 1858-1871
U-Pb isotope analyses of ores from the Schwartzwalder uranium mine, Colorado, show that these ores have high amounts of initial (common) Pb and that the initial Pb was both variable and relatively radiogenic in its Pb isotope ratios ( 206 Pb/ 204 Pb = 26-30). As a result, the only useful approach to dating...
Geophysical techniques for reconnaissance investigations of soils and surficial deposits in mountainous terrain
C.G. Olson, J.A. Doolittle
1985, Soil Science Society of America Journal (49) 1490-1498
Two techniques were assessed for their capabilities in reconnaissance studies of soil characteristics: depth to the water table and depth to bedrock beneath surficial deposits in mountainous terrain. Ground-penetrating radar had the best near-surface resolution in the upper 2 m of the profile and provided continuous interpretable imagery of soil...
Simulation of steady-state flow in three-dimensional fracture networks using the boundary-element method
A.M. Shapiro, J. Andersson
1985, Advances in Water Resources (8) 106-110
An efficient method for simulating steady-state flow in three-dimensional fracture networks is formulated with the use of the boundary-element method. The host rock is considered to be impervious, and the fractures can be of any orientation and areal extent. The fractures are treated as surfaces where fluid movement is essentially...
