Effects of tillage practices and carbofuran exposure on small mammals
Peter H. Albers, Greg L. Linder, James D. Nichols
1990, Journal of Wildlife Management (54) 135-142
We compared population estimates, body mass, movement, and blood chemistry of small mammals between conventionally tilled and no-till cornfields in Maryland and Pennsylvania to evaluate the effects of tillage practices and carbofuran exposure on small mammals. Estimates suggest that populations of white-footed mice (Peromyscus leucopus) were not significantly related (P...
Characteristics, origin, and residence time of saprolite and soil of the Piedmont Upland, Virginia, U.S.A., and model testing using cosmogenic 10Be
M.J. Pavich
1990, Chemical Geology (84) 15-16
[No abstract available]...
Pleistocene stratigraphy of the Boston Harbor drumlins, Massachusetts
W.A. Newman, R. C. Berg, P.S. Rosen, H.D. Glass
1990, Quaternary Research (34) 148-159
Evidence from the Boston Harbor drumlins indicates that two superposed tills were deposited during glacier advances which were separated by a long nonglacial interval. At Long and Peddocks Islands, argillans and truncated clay-filled fractures, along with discontinuities in clay-mineral composition, define the till contacts. Physical indicators separating the tills are...
Application of a hollow-fiber, tangential-flow device for sampling suspended bacteria and particles from natural waters
J.S. Kuwabara, R.W. Harvey
1990, Journal of Environmental Quality (19) 625-629
The design and application of a hollow-fiber tangential-flow filtration device has been used to concentrate bacteria and suspended particles from large volume surface water and groundwater samples (i.e., hundreds of liters). Filtrate tlux rates (4–8 L min−1) are equal to or faster than those of other devices that are based...
Near-surface velocities and attenuation at two boreholes near Anza, California, from logging data
Joe B. Fletcher, T. Fumal, Hsi-Ping Liu, L.C. Carroll
1990, Bulletin of the Seismological Society of America (80) 807-831
To investigate near-surface site effects in granite rock, we drilled 300-m-deep boreholes at two sites which are collocated with stations from the digital array at Anza, California. The first borehole was sited at station KNW (Keenwild fire station), which is located along a ridge line about 8.7 km east of...
Late cenozoic subduction complex of Sicily
F. Roure, D. G. Howell, C. Muller, I. Moretti
1990, Journal of Structural Geology (12) 259-266
Besides remnants of Hercynian deformations in the Peloritani nappe and of pre-Oligocene Alpine structures in the Troiani nappe, most compressive structures observed in the Sicilian accretionary wedge result from the late Cenozoic (Tortonian to Present) continental subduction of the Apulia...
High spectral resolution reflectance spectroscopy of minerals
R. N. Clark, T. V. V. King, M. Klejwa, Gregg A. Swayze, N. Vergo
1990, Journal of Geophysical Research Solid Earth (95) 12653-12680
The reflectance spectra of minerals are studied as a function of spectral resolution in the range from 0.2 to 3.0 μm. Selected absorption bands were studied at resolving powers (λ/Δλ) as high as 2240. At resolving powers of approximately 1000, many OH‐bearing minerals show diagnostic sharp absorptions at the resolution...
Chronologic and isotopic framework for early Proterozoic crustal evolution in the eastern Mojave Desert region, SE California
J. L. Wooden, D. M. Miller
1990, Journal of Geophysical Research (95) 20133-20146
The Early Proterozoic geologic evolution of the eastern Mojave Desert region, as defined by characteristics of its supracrustal rocks, granitoids, metamorphism, structural history, and Pb and Nd isotopic signature, contrasts sharply with other Proterozoic provinces of the southwestern United States. The oldest supracrustal rocks of the Mojave Desert region contain...
Early Holocene pecan, Carya illinoensis, in the Mississippi River Valley near Muscatine, Iowa
E. Arthur Bettis III, R. G. Baker, B.K. Nations, D.W. Benn
1990, Quaternary Research (33) 102-107
A fossil pecan, Carya illinoensis (Wang.) K. Koch, from floodplain sediments of the Mississippi River near Muscatine, Iowa, was accelerator-dated at 7280 ?? 120 yr B.P. This discovery indicates that pecan was at or near its present northern limit by that time. Carya pollen profiles from the Mississippi River Trench...
Deep drilling at the Siljan Ring impact structure: oxygen-isotope geochemistry of granite
S.C. Komor, J.W. Valley
1990, Contributions to Mineralogy and Petrology (105) 516-532
The Siljan Ring is a 362-Ma-old impact structure formed in 1700-Ma-old I-type granites. A 6.8-km-deep borehole provides a vertical profile through granites and isolated horizontal diabase sills. Fluid-inclusion thermometry, and oxygen-isotope compositions of vein quartz, granite, diabase, impact melt, and pseudotachylite, reveal a complex history of fluid activity in the...
An investigation of spectral change as influenced by irrigation and evapotranspiration volume estimation in western Nebraska
P. M. Seevers, F.C. Sadowski, D. T. Lauer
1990, Climatic Change (17) 265-285
Retrospective satellite image data were evaluated for their ability to demonstrate the influence of center-pivot irrigation development in western Nebraska on spectral change and climate-related factors for the region. Periodic images of an albedo index and a normalized difference vegetation index (NDVI) were generated from calibrated Landsat multispectral scanner (MSS)...
Source parameters for small events associated with the 1986 North Palm Springs, California, earthquake determined using empirical Green functions
J. Mori, A. Frankel
1990, Bulletin of the Seismological Society of America (80) 278-295
Using small events as empirical Green functions, which include path, site, and instrument effects on the P waveforms, source parameters were estimated for 25 ML 3.4 to 4.4 events associated with the 1986 North Palm Springs earthquake. The static stress drops ranged from 3 to 80 bars, for moments of...
A tomographic glimpse of the upper mantle source of magmas of the Jemez lineament, New Mexico
W. Spence, R.S. Gross
1990, Journal of Geophysical Research Solid Earth (95) 10829-10849
The 800-km-long Jemez lineament is the most active volcanic feature in the southwestern United States. It is the southeastern tectonic boundary of the Colorado Plateau and crosses the Rio Grande rift at the Jemez Mountains. The primary volcanism of the lineament is basaltic and has occurred in the last 4.5...
Postglacial response of a stream in central Iowa to changes in climate and Drainage basin factors
J. Van Nest, E. Arthur Bettis III
1990, Quaternary Research (33) 73-85
Postglacial geomorphic development of the Buchanan Drainage, a small tributary to the South Skunk River, is reconstructed by documenting relationships among four allostratigraphic units and 17 radiocarbon dates. Formation and headward expansion of the valley was both episodic and time-transgressive. Response to downstream conditions in the South Skunk River largely...
Thermal history of rocks in southern San Joaquin Valley, California: evidence from fission-track analysis
Nancy D. Naeser, Charles W. Naeser, Thane H. McCulloh
1990, American Association of Petroleum Geologists Bulletin (74) 13-29
The theory of the fission-track method and its application to sedimentary basin analysis is illustrated by a case study in the southern San Joaquin Valley, California. Fission tracks provide a powerful tool for studying the thermal history of sedimentary basins because the two minerals most commonly used in fission-track studies,...
Method to estimate center of rigidity using vibration recordings
Erdal Safak, Mehmet Çelebi
1990, Journal of Structural Engineering (116) 85-97
A method to estimate the center of rigidity of buildings by using vibration recordings is presented. The method is based on the criterion that the coherence of translational motions with the rotational motion is minimum at the center of rigidity. Since the coherence is a function of frequency, a gross...
Some hydrological impacts of climate change for the Delaware River Basin
Gary D. Tasker
1990, Conference Paper
To gain insight into possible impacts of climate change on water availability in the Delaware River, two models are linked. The first model is a monthly water balance model that converts the temperature and precipitation values generated by a random number generator to monthly streamflow values. The monthly streamflow values...
Enigmatic eight-meter trace fossils in the Lower Pennsylvanian Lee sandstone, central Appalachian basin, Tennessee
C. Wnuk, J. O. Maberry
1990, Journal of Paleontology (64) 440-450
Enigmatic tubular trace fossils up to eight meters long occur in the Lower Pennsylvanian Middlesboro Member of the Lee Formation. Two morphotypes occur: type 1 trace fossils are plain, smooth, vertical, nonbranching, parallel-walled, tubular structures; type 2 trace fossils branch, have walls with faint vertical striations, regularly...
Natural sources of greenhouse gases: carbon dioxide emissions from volcanoes
Terrence Gerlach
1990, Conference Paper, Transactions - Geothermal Resources Council
Volcanic degassing of carbon dioxide plays an important role in keeping the atmosphere-ocean portion of the carbon geochemical cycle in balance. The atmosphere-ocean carbon deficit requires replenishment of 6??1012 mol CO2/yr, and places an upper limit on the output of carbon dioxide from volcanoes. The CO2 output of the global...
Origin of carbonate deposits in the vicinity of Yucca Mountain, Nevada. Preliminary results of strontium-isotope analyses
B.D. Marshall, K. Futa, S. A. Mahan, Z. E. Peterman, J. S. Stuckless, J. S. Downey, E. D. Gutentag
1990, Conference Paper
As part of the paleohydrology study of the Yucca Mountain Project, strontium-isotope analyses of carbonate deposits, ground water, and major rock reservoirs of strontium are in progress. This paper presents a summary of the strontium-isotope data obtained through 1989. Calcium carbonate is ubiquitous in the vicinity of Yucca Mountain, where...
An evaluation of the accuracy of geomagnetic data obtained from an unattended, automated, quasi-absolute station
D.C. Herzog
1990, Physics of the Earth and Planetary Interiors (59) 112-118
A comparison is made of geomagnetic calibration data obtained from a high-sensitivity proton magnetometer enclosed within an orthogonal bias coil system, with data obtained from standard procedures at a mid-latitude U.S. Geological Survey magnetic observatory using a quartz horizontal magnetometer, a Ruska magnetometer, and a total field magnetometer. The orthogonal...
Fractal characterization of fracture surfaces in concrete
V. E. Saouma, Christopher C. Barton, N. A. Gamaleldin
1990, Engineering Fracture Mechanics (35) 47-53
Fractal geometry is used to characterize the roughness of cracked concrete surfaces through a specially built profilometer, and the fractal dimension is subsequently correlated to the fracture toughness and direction of crack propagation. Preliminary results indicate that the fracture surface is indeed fractal over two orders of magnitudes with a...
Phase relations in the system CuMoS
H. Dawei, L.L.Y. Chang, C.R. Knowles
1990, Journal of the Less-Common Metals (163) 281-286
Phase relations in the system CuMoS were studied in the temperature range 500-1000 ??C by using the conventional sealed, evacuated glass capsule technique. Reflected-light microscopy, X-ray powder diffraction and electron microprobe analysis were used for phase characterization. The chevrel-type phase, CuxMo3S4, is stable above 600??C, and forms equilibrium assemblages with...
Comparison of methods to determine degree of pyritization
J. Leventhal, C. Taylor
1990, Geochimica et Cosmochimica Acta (54) 2621-2625
Degree of pyritization (DOP) is a measure of the ratio pyrite iron/(pyrite iron + reactive iron) that can be related to the depositional environment of a sediment. Several methods of DOP determination have been used but not systematically evaluated. The determination/extraction of reactive (usually acid soluble) iron is critical to...
Oxygen isotope map of the giant metamorphic-hydrothermal system around the northern part of the Idaho batholith, U.S.A.
R.E. Criss, R.J. Fleck
1990, Applied Geochemistry (5) 641-655
Determinations of δ18O values from 100 outcrops of Belt Supergroup (Wallace Fm.) metasedimentary rocks in the Idaho panhandle reveal a regular regional pattern that was produced by pervasive fluid infiltration and isotopic exchange. Low grade argillites at large distances (60 km)...
