Early Cretaceous vein-related garnet granulite in Fiordland, southwest New Zealand: a case for infiltration of mantle-derived CO2-rich fluids
J.Y. Bradshaw
1989, Journal of Geology (97) 697-717
Regionally extensive two-pyroxene granulite facies orthogneisses of Early Cretaceous age in Fiordland, southwest New Zealand, are criss-crossed by garnet-bearing feldspathic veins (and dikes) having associated marginal reaction zones of garnet granulite. The two-pyroxene granulites resulted from fluid-absent meta-morphism of a suite of...
Sensitive strata in Bootlegger Cove Formation
Harold W. Olsen
1989, Journal of Geotechnical Engineering (115) 1239-1251
Sensitivity magnitudes are interpreted from remolded strength values in recent subsurface geologic, geotechnical, and geochemical data from the Bootlegger Cove Formation adjacent to the Turnagain Heights Landslide. The results show that strata composed of highly sensitive clays occur in both the middle and lower zones of the formation, and that...
Extraction of terrain features from digital elevation models
Curtis V. Price, David M. Wolock, Mark A. Ayers
1989, Conference Paper
Digital elevation models (DEMs) are being used to determine variable inputs for hydrologic models in the Delaware River basin. Recently developed software for analysis of DEMs has been applied to watershed and streamline delineation. The results compare favorably with similar delineations taken from topographic maps. Additionally, output from this software...
Data-collection program for Pamlico River Estuary model calibration and validation
Jerad D. Bales
1989, Conference Paper
An investigation is being conducted to collect and interpret continuous records relating to the flow characteristics of the Pamlico River Estuary, North Carolina, and to calibrate and validate a numerical model of estuarine hydrodynamics. The study reach is 50 kilometers long and ranges in width from 330 meters at the...
Surface faulting: A preliminary view
R. V. Sharp
1989, Earthquake Spectra (5) 13-22
This description of surface faulting near Spitak, Armenia, is based on a field inspection made December 22-26, 1988. The surface rupture west of Spitak, displacement of the ground surface, pre-earthquake surface expressions of the fault, and photolineaments in landsat images are described and surface faulting is compared to aftershocks. It...
Thermodynamics of magnesian calcite solid-solutions at 25°C and 1 atm total pressure
Eurybiades Busenberg, Niel Plummer
1989, Geochimica et Cosmochimica Acta (53) 1189-1208
The stability of magnesian calcites was reexamined, and new results are presented for 28 natural inorganic, 12 biogenic, and 32 synthetic magnesian calcites. The magnesian calcite solid-solutions were separated into two groups on the basis of differences in stoichiometric solubility and other physical and chemical properties. Group I consists...
The Alabama, U.S.A., seismic event and strata collapse of May 7, 1986
L.T. Long, C.W. Copeland
1989, Pure and Applied Geophysics PAGEOPH (129) 415-421
On May 7, 1986, the residents of Tuscaloosa, Alabama, felt a seismic event of local magnitude 3.6 that occurred at the same time as a rock burst and roof collapse in an active longwall coal mine. Visual inspection of the seismograms reveals a deficiency in energy at frequencies above 20...
Note
D.M. Moore, R.E. Hughes
1989, Catalysis Letters (2) 71-72
[No abstract available]...
Heat capacities and entropies from 8 to 1000 K of langbeinite (K2Mg2(SO4)3), anhydrite (CaSO4) and of gypsum (CaSO4·2H2O)
Richard A. Robie, Susan Russell-Robinson, Bruce S. Hemingway
1989, Thermochimica Acta (139) 67-81
Heat capacities of K2Mg2(SO4)3 (langbeinite) and CaSO4 (anhydrite) were measured from approximately 8 to 1000 K by combined adiabatic shield calorimetry (8-365 K) and differential scanning calorimetry (350-1000 K). Heat capacities were also measured on natural crystals of gypsum (CaSO4 · 2H2O) between 8.1 and 323.5 K. The molar entropies at 298.15...
Effect of flow conditions on stream reaeration coefficients
James L. Smoot
1989, Conference Paper
Contrary to the findings of previous studies of channel-controlled stream reaches, it was found that, in four reaches of a small stream characterized by a series of pools and riffles, reaeration coefficients decrease with decreasing discharge. In the reach with the most pool-and-riffle development, the measured reaeration coefficient under low-flow...
Recharge of the early atmosphere of Mars by impact-induced release of CO2
Michael H. Carr
1989, Icarus (79) 311-327
Channels on the Martian surface suggest that Mars had an early, relatively thick atmosphere. If the atmosphere was thick enough for water to be stable at the surface, CO2 in the atmosphere would have been fixed as carbonates on a relatively short time scale, previously estimated to be 1 bar...
Source and origin of Roxana Silt and middle Wisconsinan midcontinent glacial activity
W.H. Johnson, L.R. Follmer
1989, Quaternary Research (31) 319-331
Thick Roxana Silt (middle Wisconsinan) in central and southwestern Illinois traditionally has been interpreted as loess derived from valley-train deposits in the ancient Mississippi River valley. Winters et al. (H. A. Winters, J. J. Alford, and R. L. Rieck, Quaternary Research 29, 25-35, 1988) recently suggested that the Roxana was...
Isotopic constraints on the genesis of base-metal ores in southern and central Sardinia
K.R. Ludwig, R. Vollmer, B. Turi, K. R. Simmons, G. Perna
1989, European Journal of Mineralogy (1) 657-666
The Pb-Zn-Ag deposits of southwestern and central Sardinia occur within a restricted region, but comprise a variety of mineralization ages and styles. New Pb-isotope data, together with published data provide a reasonably coherent picture of possible sources for the various types of deposits. -from Authors...
Nitrogen dynamics in the tidal freshwater Potomac River, Maryland and Virginia, water years 1979-81
David J. Shultz
1989, Water Supply Paper 2234-J
On an annual basis, river-supplied nitrate is the predominant form of nitrogen supplied to the tidal Potomac River from external sources. Much of the nitrate is associated with high flows that have rapid transit times through the tidal river. The Blue Plains Sewage-Treatment Plant (STP) at Washington, D.C., is the...
Whitings, a sedimentologic dilemma
E.A. Shinn, R.P. Steinen, B. H. Lidz, Peter K. Swart
1989, Journal of Sedimentary Petrology (59) 147-161
Whitings, drifting clouds of water, milky because of suspended carbonate, have been claimed to originate from either the action of bottom-feeding fish or direct precipitation of calcium carbonate. Five cruises during different seasons were made to the Great Bahama Bank to collect data...
Comparison of geoelectrical/tectonic models for suture zones in the western U.S.A. and eastern Europe: are black shales a possible source of high conductivities?
W. D. Stanley
1989, Physics of the Earth and Planetary Interiors (53) 228-238
Large-scale geoelectrical anomalies have been mapped with geomagnetic depth sounding (GDS) and magnetotelluric (MT) surveys in the Carpathian Mountains region. These anomalies are associated with the zone of closure between stable Europe and a complex of microplates in front of the converging African plate. The zone of closure, or suture...
Simulation of calcite dissolution and porosity changes in saltwater mixing zones in coastal aquifers
Ward E. Sanford, Leonard F. Konikow
1989, Water Resources Research (25) 655-667
Thermodynamic models of aqueous solutions have indicated that the mixing of seawater and calcite-saturated fresh groundwater can produce a water that is undersaturated with respect to calcite. Mixing of such waters in coastal carbonate aquifers could lead to significant amounts of limestone dissolution. The potential for such dissolution in coastal...
Absence of Altonian glaciation in Illinois
B. Brandon Curry
1989, Quaternary Research (31) 1-13
Illinois was free of glacier ice from about 130,000 to 25,000 yr B.P. Deposits of this time interval in northeastern Illinois, represented by core samples from test-hole ISGS S-30, are composed of leached, nonglacigenic, stratified, or pedoturbated silty sediments that typically are organic-rich and pedogenically modified. These deposits overlie the...
Shape-selective adsorption of aromatic molecules from water by tetramethylammonium-smectite
J. Lee, M.M. Mortland, S.A. Boyd, C. T. Chiou
1989, Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases (85) 2953-2962
The adsorption of aromatic compounds by smectite exchanged with tetramethylammonium (TMA) has been studied. Aromatic compounds adsorbed by TMA-smectite are assumed to adopt a tilted orientation in a face-to-face arrangment with the TMA tetrahedra. The sorptive characteristics of TMA-smectite were influenced strongly by the presence of water. The dry TMA-smectite...
Thermal stresses due to cooling of a viscoelastic oceanic lithosphere
R.P. Denlinger, W. Z. Savage
1989, Journal of Geophysical Research Solid Earth (94) 744-752
Theories based upon thermal contraction of cooling oceanic lithosphere provide a successful basis for correlating seafloor bathymetry and heat flow. The horizontal components of the contraction of the lithosphere as it cools potentially give rise to large thermal stresses. Current methods to calculate these stresses assume that on the time...
Water balance at a low-level radioactive-waste disposal site
R. W. Healy, J. R. Gray, G. M. De Vries, P. C. Mills
1989, Water Resources Bulletin (25) 381-390
The water balance at a low-level radioactive-waste disposal site in northwestern Illinois was studied from July 1982 through June 1984. Continuous data collection allowed estimates to be made for each component of the water-balance equation independent of other components. The average annual precipitation was 948 millimeters. Average annual evapotranspiration was...
Seismic reflection images of the crust of the northern part of the Chugach terrane, Alaska: Results of a survey for the Trans-Alaska Crustal Transect (TACT)
M. A. Fisher, T.M. Brocher, W. J. Nokleberg, George Plafker, G.L. Smith
1989, Journal of Geophysical Research Solid Earth (94) 4424-4440
Deep crustal seismic reflection data show strong reflections from the middle and lower crust of the convergent continental margin near the eastern end of the Aleutian trench. These data were collected across the Border Ranges fault system, a major suture zone that separates the Peninsular and Chugach tectonostratigraphic terranes. The...
Volume predictability of historical eruptions at Kilauea and Mauna Loa volcanoes
C.-Y. King
1989, Journal of Volcanology and Geothermal Research (38) 281-285
Cumulative volumes of eruptions at the Kilauea and Mauna Loa volcanoes in Hawaii appear to fit a volume-predictable model (i.e., the volume of an eruption episode is approximately proportional to the time since the previous episode) for many larger episodes during long periods of time (decades). This observation suggests that...
Geology of the Ulugh Muztagh area, northern Tibet
B.C. Burchfiel, P. Molnar, Ziyun Zhao, K’uangyi Liang, Shuji Wang, Minmin Huang, J. Sutter
1989, Earth and Planetary Science Letters (94) 57-70
Within the Ulugh Muztagh area, north central Tibet, an east-west-trending ophiolitic melange marks a suture that apparently was formed during a late Triassic or slightly younger collision between a continental fragment to the south and the rest of Asia. The southern continental fragment carries a thick sequence of upper Triassic...
Late Neogene geohistory analysis of the Humboldt basin and its relationship to convergence of the Juan de Fuca plate
P.A. McCrory
1989, Journal of Geophysical Research Solid Earth (94) 3126-3138
Geohistory analysis of Neogene Humboldt basin strata provides important constraints for hypotheses of the tectonic evolution of the southern Cascadia subduction margin, leading up to the arrival of the Mendocino triple junction. This analysis suggests that the tectonic evolution of the Humboldt basin area was dominated by coupling between the...
