Landslides caused by earthquakes
D. K. Keefer
1984, Geological Society of America Bulletin (95) 406-421
Data from 40 historical world-wide earthquakes were studied to determine the characteristics, geologic environments, and hazards of landslides caused by seismic events. This sample of 40 events was supplemented with intensity data from several hundred United States earthquakes to study relations between landslide...
Geochronology of Precambrian granites and associated U-Ti-Th mineralization, northern Olary province, South Australia
K.R. Ludwig, J.A. Cooper
1984, Contributions to Mineralogy and Petrology (86) 298-308
Proterozoic granitoids and metamorphic rocks in the Olary province of the Willyama block of South Australia host ore-grade amounts of U-Th-Ti and U-Fe-Ti-Th minerals. U-Pb-Th isotope analyses on zircons from all granitoids associated with the Crocker Well brannerite deposit indicate that these granitoids were intruded within a short time span,...
Mineral resources of the Atlantic Exclusive Economic Zone
William P. Dillon
1984, Conference Paper, Oceans Conference Record (IEEE)
Potential mineral resources of the Atlantic Exclusive Economic Zone (including the Gulf of Mexico and US Caribbean areas) include petroleum, sand and gravel, phosphorite, placer deposits of heavy mineral sands, ferromanganese nodules, and fresh water. Although major efforts have been made to search for petroleum, the oil and gas resources...
Manganese-rich red tourmaline from the Fowler talc belt, New York.
R. A. Ayuso, C. Erwin Brown
1984, Canadian Mineralogist (22) 327-331
Red uvite containing up to 4.34 wt.% MnO is found in the Arnold talc mine near Fowler, New York, USA. Microprobe analyses give a composition of 51% uvite in the uvite-dravite series. Associated minerals in this manganiferous metamorphic assemblage (possibly an evaporite) are manganese-rich tremolite (hexagonite) braunite and quartz.-R.A.G....
Evaluation of metal ion absorptive characteristics of three types of plastic sample bags used for pecipitation sampling
A.B. Good, L.J. Schroder
1984, Journal of Environmental Science and Health - Part A Environmental Science and Engineering (19) 631-640
Simulated precipitation samples containing 16 metal ions were prepared at 4 pH values. Absorptive characteristics of polypropylene, polyethylene, and polyester/polyolefin sacks were evaluated at pH 3.5, 4.0, 4.5, and 5.0. Simulated precipitation was in contact with the sacks for 17 days, and subsamples were removed for chemical analysis at 3,...
Concentrations and isotope ratios of carbon, nitrogen and sulfur in ocean-floor basalts
H. Sakai, D.J.D. Marais, A. Ueda, J.G. Moore
1984, Geochimica et Cosmochimica Acta (48) 2433-2441
Fresh submarine basalt glasses from Galapagos Ridge, FAMOUS area, Cayman Trough and Kilauea east rift contain 22 to 160 ppm carbon and 0.3 to 2.8 ppm nitrogen, respectively, as the sums of dissolved species and vesicle-filling gases (CO2 and N2). The large range of variation in carbon content is due to...
Optimization of electrothermal atomization parameters for simultaneous multielement atomic absorption spectrometry
J. M. Harnly, Jean S. Kane
1984, Analytical Chemistry (56) 48-54
The effect of the acid matrix, the measurement mode (height or area), the atomizer surface (unpyrolyzed and pyrolyzed graphite), the atomization mode (from the wall or from a platform), and the atomization temperature on the simultaneous electrothermal atomization of Co, Cr, Cu, Fe, Mn, Mo, Ni, V, and Zn was...
The solubility of strontianite (SrCO3) in CO2-H2O solutions between 2 and 91°C, the association constants of SrHCO+3(aq) and SrCO03(aq) between 5 and 80°C, and an evaluation of the thermodynamic properties of Sr2+(aq) and SrCO3(cr) at 25°C and 1 atm total pressure
Eurybiades Busenberg, Niel Plummer, Vivian B. Parker
1984, Geochimica et Cosmochimica Acta (48) 2021-2035
Seventy new measurements (SrT-Pco2 of the solubility of strontianite were used to evaluate the equilibrium constant for the reaction SrCO3(cr) = Sr2+(aq) + CO2−3(aq) between 2 and 91 °C. The temperature dependence of the equilibrium constant is given by the expression Log K = 155.0305 − 7239.594/T − 56.58638 log T where T is in degrees Kelvin. The log K of strontianite,...
Isolation of organic acids from large volumes of water by adsorption chromatography
George R. Aiken
1984, Book, National Meeting - American Chemical Society, Division of Environmental Chemistry
The concentrations of dissolved organic carbon from most natural waters ranges from 1 to 20 milligrams carbon per liter, of which approximately 75 percent are organic acids. These acids can be chromatographically fractionated into hydrophobic organic acids, such as humic substances, and hydrophilic organic acids. To effectively study any of...
Propagation and linkage of oceanic ridge segments
David D. Pollard, Atilla Aydin
1984, Journal of Geophysical Research Solid Earth (89) 10017-10028
We have investigated the propagation of spreading ridges and the development of structures that link ridge segments using an analogy between ridges and cracks in elastic plates. The ridge-propagation force and a path factor that controls propagation direction were calculated for echelon ridge segments propagating toward each other. The ridge-propagation...
San Agustin Plains, New Mexico: Age and paleoenvironmental potential reassessed
Vera Markgraf, J.P. Bradbury, R. M. Forester, G. Singh, R.S. Sternberg
1984, Quaternary Research (22) 336-343
Paleomagnetic analysis of samples from the original 600-m-long core from the San Agustin Plains, New Mexico, showed an unquestionable reversal stratigraphy dating the record back to at least 1.6 my. Analysis of pollen, ostracodes, and algae of a duplicate sample section in the vicinity of the original coring site and...
Comparative geochronology in the reversely zoned plutons of the Bottle Lake Complex, Maine: U-Pb on zircons and Rb-Sr on whole rocks
R. A. Ayuso, Joseph G. Arth, A.K. Sinha, J. Carlson, D. R. Wones
1984, Contributions to Mineralogy and Petrology (88) 113-125
The Bottle Lake Complex is a composite granitic batholith emplaced into Cambrian to Lower Devonian metasedimentary rocks. Both plutons (Whitney Cove and Passadumkeag River) are very coarse grained hornblende and biotite-bearing granites showing petrographic and geochemical reverse zonation. Two linear whole rock Rb/Sr isochrons on xenolith-free Whitney Cove and Passadumkeag...
Midseason mapping of sunflowers using Landsat digital data
W.H. Anderson, D.O. Ohlen, S.D. Fairaizl
1984, Journal of Wildlife Management (48) 295-298
The mapping results suggest that for the midsummer Landsat data used, there was not a sufficiently reliable relationship between Landsat-derived spectral clusters and sunflowers to allow 'automated' production of useful sunflower location maps. The occurrence of sunflower pixels in all cluster classes was a consequence of the diversity in sunflower...
Geology of El Chichon volcano, Chiapas, Mexico
W. A. Duffield, R.I. Tilling, R. Canul
1984, Journal of Volcanology and Geothermal Research (20) 117-132
The (pre-1982) 850-m-high andesitic stratovolcano El Chicho??n, active during Pleistocene and Holocene time, is located in rugged, densely forested terrain in northcentral Chiapas, Me??xico. The nearest neighboring Holocene volcanoes are 275 km and 200 km to the southeast and northwest, respectively. El Chicho??n is built on Tertiary siltstone and sandstone,...
The group separation of the rare-earth elements and yttrium from geologic materials by cation-exchange chromatography
J.G. Crock, F.E. Lichte, T.R. Wildeman
1984, Chemical Geology (45) 149-163
Demand is increasing for the determination of the rare-earth elements (REE) and yttrium in geologic materials. Due to their low natural abundance in many materials and the interferences that occur in many methods of determination, a separation procedure utilizing gradient strong-acid cation-exchange chromatography is often used to preconcentrate and isolate...
Chemical determination of particulate nitrogen in San Francisco Bay. A comparison of two estimates
S.W. Hager, D.D. Harmon
1984, Estuarine, Coastal and Shelf Science (19) 181-191
Particulate nitrogen was measured by both the ultra-violet light-catalyzed peroxide method and the high temperature combustion method. The difference between values obtained with the two methods (combustion minus UV) was found to be linearly correlated with the concentration of total suspended particulate matter (SPM) in the sample. The slope of...
Heating of a fully saturated Darcian half-space: Pressure generation, fluid expulsion, and phase change
P. Delaney
1984, International Journal of Heat and Mass Transfer (27) 1327-1335
Analytical solutions are developed for the pressurization, expansion, and flow of one- and two-phase liquids during heating of fully saturated and hydraulically open Darcian half-spaces subjected to a step rise in temperature at its surface. For silicate materials, advective transfer is commonly unimportant in the liquid region; this is not...
Botanical and geological significance of potassium-argon dates from the Juan Fernández Islands
Tod F. Stuessy, K.A. Foland, John F. Sutter, Roger W. Sanders, O. Mario Silva
1984, Science (225) 49-51
Potassium-argon dating of five basalts from the three main islands of the Juan Fernández (or Robinson Crusoe) Islands of Chile in the southeastern Pacific gives ages of 1.01 ± 0.12 and 2.44 ± 0.14 million years for Masafuera, 3.79 ± 0.20 and 4.23 ± 0.16 for Masatierra, and 5.8 ±...
Glacier mass balance and runoff research in the U.S.A.
L.R. Mayo
1984, Geografiska Annaler, Series A (66 A) 215-227
Research on glacier mass balance began in the U.S.A. about 50 years ago. More complete studies of climate, snow and ice balance, and the hydrology of glaciers were initiated for the IGY in 1957 and the IHD in 1966. Investigations included the magnitude and geographic distribution of normal...
Dendrogeomorphic evidence of debris flow frequency and magnitude at Mount Shasta, California
Cliff R. Hupp
1984, Environmental Geology and Water Sciences (6) 121-128
Debris-flow deposits and woody vegetation adjacent to and growing within the channels of Whitney, Bolam, Mud, Ash, and Panthe creeks provide a 300-year record of debris-flow frequency at Mount Shasta Dendrochronologic (tree-ring) dating methods for the debris flows proved consistent with available documented records of debris flows Nine debris flows...
Compton suppression gamma-counting: The effect of count rate
Hugh T. Millard Jr.
1984, Nuclear Instruments and Methods In Physics Research (223) 416-419
Past research has shown that anti-coincidence shielded Ge(Li) spectrometers enhanced the signal-to-background ratios for gamma-photopeaks, which are situated on high Compton backgrounds. Ordinarily, an anti- or non-coincidence spectrum (A) and a coincidence spectrum (C) are collected simultaneously with these systems. To be useful in neutron activation analysis (NAA), the fractions...
Pedimentation versus debris-flow origin of plateau-side desert terraces in southern Utah
V. S. Williams
1984, Journal of Geology (92) 457-468
Plateau-side terraces in arid areas around the world are commonly described as pediment remnants, although, in many cases, they may have been formed by debris-flow deposition. Pediments do exist in the area of the Aquarius and Kaiparowits Plateaus of southern Utah; however, many alluvial terraces that were classified by previous...
Field and laboratory analyses of water from the Columbia aquifer in Eastern Maryland
L. J. Bachman
1984, Groundwater (22) 460-469
Field and laboratory analyses of pH, alkalinity, and specific conductance from water samples collected from the Columbia aquifer on the Delmarva Peninsula in eastern Maryland were compared to determine if laboratory analyses could be used for making regional water-quality interpretations.On the basis of 170 field...
Relationship between quantity and quality of storm runoff and various watershed characteristics in Minnesota, USA
Rob G. Brown
1984, Conference Paper
Watersheds are rural areas undergoing urbanization with current urban land use comprising 4 to 58 percent of the watershed area. The quantity and quality of storm runoff in the watersheds was tested for correlations (significance level of 0. 05) with various land-surface features and landuse characteristics. Quantity of storm runoff...
Craggy Mountain Wilderness Study Area and Extension, North Carolina
Frank G. Lesure, Bradford B. Williams
1984, Book chapter, Wilderness mineral potential: assessment of mineral-resource potential in U.S. Forest Service lands studied in 1964-1984: Volume II (Professional Paper 1300)
Craggy Mountain Wilderness Study Area and the adjoining Craggy Mountain Extension consist of more than 4 sq mi of steep wooded slopes on the west side of Great Craggy Mountain in the Blue Ridge of western North Carolina. A mineral-resource survey of the area done between 1976 and 1979 found...
