Detrital zircon geochronology of Neoproterozoic to Middle Cambrian miogeoclinal and platformal strata: Northwest Sonora, Mexico
E.L. Gross, John H. Stewart, G.E. Gehreis
2000, Geofisica Internacional (39) 295-308
Eighty-five detrital zircon grains from Mesoproterozoic and/or Neoproterozoic to Middle Cambrian sedimentary strata in northwest Sonora, Mexico, have been analyzed to determine source terranes and provide limiting depositional ages of the units. The zircon suites from the Mesoproterozoic and/or Neoproterozoic El Alamo Formation and El Aguila unit yield ages between...
Composition of Pteryxia terebinthina var. californica (Coult. and Rose) Mathias essential oils
Philip E. Beauchamp, Vasu Dev, Elsa Munevar-Mendoza, Peggy E. Moore
2000, Journal of Essential Oil Research (12) 372-376
β-Pinene (35.0%, 53.8%) was the major component of both the aerial parts and the root oils of Pteryxia terebinthina var. californica, respectively. β-Phellandrene (12.2%) was the other most abundant component of the oil from aeial parts while δ-3-carene (14.2%) was the second abundant component of the root oil....
Nitrogen solutes in an Adirondack forested watershed: Importance of dissolved organic nitrogen
M.R. McHale, M.J. Mitchell, Jeffery J. McDonnell, C.P. Cirmo
2000, Biogeochemistry (48) 165-184
Nitrogen (N) dynamics were evaluated from 1 June 1995 through 31 May 1996 within the Arbutus Lake watershed in the Adirondack Mountains of New York State, U.S.A. At the Arbutus Lake outlet dissolved organic nitrogen (DON), NO3/- and NH4/+ contributed 61%, 33%, and 6% respectively, to the total dissolved nitrogen...
USGS World Petroleum Assessment 2000: New Conventional Provinces
Thomas S. Ahlbrandt, T. R. Klett
2000, Conference Paper, World Petroleum Congress Proceedings
The USGS has completed a new assessment of the undiscovered oil and gas resources of the world. One hundred and five geologic provinces were analyzed for assessment. Assessment units (AU) that comprise Total Petroleum Systems (TPS) were identified and described for each of these provinces. The AU served as the...
Compositing water samples for analysis of volatile organic compounds
T. J. Lopes, J. D. Fallon, T.L. Maluk
2000, Journal of Environmental Engineering (126) 769-773
Accurate mean concentrations of volatile organic compounds (VOCs) can easily and economically be obtained from a single VOC analysis by using proven methods of collecting representative, discrete water samples and compositing them with a gas-tight syringe. The technique can be used in conjunction with chemical analysis by a conventional laboratory,...
Diagenetic fate of organic contaminants on the Palos Verdes Shelf, California
R.P. Eganhouse, J. Pontolillo, T.J. Leiker
2000, Marine Chemistry (70) 289-315
Municipal wastes discharged through deepwater submarine outfalls since 1937 have contaminated sediments of the Palos Verdes Shelf. A site approximately 6–8 km downcurrent from the outfall system was chosen for a study of the diagenetic fate of organic contaminants in the waste-impacted sediments. Concentrations of three classes of hydrophobic organic...
High-resolution seismic reflection to delineate shallow gas in Eastern Kansas
R. D. Miller, W.L. Watney, D.K. Begay, J. Xia
2000, The Compass: Earth Science Journal of Sigma Gamma Epsilon (75) 134-145
Unique amplitude characteristics of shallow gas sands within Pennsylvanian clastic-carbonate dominated sequences are discernible on high-resolution seismic reflection data in eastern Kansas. Upward grading sequences of sand into shale represent a potential gas reservoir with a low-impedence acoustic contrast at the base of the encasing layer. The gas sand and...
Ruby and sapphire from Jegdalek, Afghanistan
G.W. Bowersox, E.E. Foord, B.M. Laurs, J.E. Shigley, C.P. Smith
2000, Gems and Gemology (36) 110-126
This study provides detailed mining and gemological information on the Jegdalek deposit, in east-central Afghanistan, which is hosted by elongate beds of corundum-bearing marble. Some facet-grade ruby has been recovered, but most of the material consists of semitransparent pink sapphire of cabochon or carving quality. The most common internal features...
Quantification and regionalization of groundwater recharge in South-Central Kansas: Integrating field characterization, statistical analysis, and GIS
M. Sophocleous
2000, The Compass: Earth Science Journal of Sigma Gamma Epsilon (75) 101-115
A practical methodology for recharge characterization was developed based on several years of field-oriented research at 10 sites in the Great Bend Prairie of south-central Kansas. This methodology combines the soil-water budget on a storm-by-storm year-round basis with the resulting watertable rises. The estimated 1985-1992 average annual recharge was less...
Correlation of 1- to 10-Hz earthquake resonances with surface measurements of S-wave reflections and refractions in the upper 50 m
R. A. Williams, W. J. Stephenson, A.D. Frankel, E. Cranswick, M. E. Meremonte, J. K. Odum
2000, Bulletin of the Seismological Society of America (90) 1323-1331
Resonances observed in earthquake seismograms recorded in Seattle, Washington, the central United States and Sherman Oaks, California, are correlated with each site's respective near-surface seismic velocity profile and reflectivity determined from shallow seismic-reflection/refraction surveys. In all of these cases the resonance accounts for the highest amplitude shaking at the site...
Gap analysis: Concepts, methods, and recent results
M.D. Jennings
2000, Landscape Ecology (15) 5-20
Rapid progress is being made in the conceptual, technical, and organizational requirements for generating synoptic multi-scale views of the earth's surface and its biological content. Using the spatially comprehensive data that are now available, researchers, land managers, and land-use planners can, for the first time, quantitatively place landscape units -...
Dominance of an ~150-year cycle of sand-supply change in late Holocene dune-building along the eastern shore of Lake Michigan
W.L. Loope, A.F. Arbogast
2000, Quaternary Research (54) 414-422
Outcrops of buried soils on lake-plains and glacial headlands along Lake Michigan's eastern shore suggest that periodic dune-building has occurred there after relatively long (≥100 yr) periods of low sand supply. We located, described, and radiocarbon dated 75 such buried soils that crop out in 32 coastal dune fields beside...
Chapter 4. Predicting post-fire erosion and sedimentation risk on a landscape scale
L. H. MacDonald, R. Sampson, D. Brady, L. Juarros, Deborah A. Martin
2000, Journal of Sustainable Forestry (11) 57-87
Historic fire suppression efforts have increased the likelihood of large wildfires in much of the western U.S. Post-fire soil erosion and sedimentation risks are important concerns to resource managers. In this paper we develop and apply procedures to predict post-fire erosion and sedimentation risks on a pixel-, catchment-, and landscape-scale...
Identification of juvenile fall versus spring chinook salmon migrating through the lower Snake River based on body morphology
K.F. Tiffan, D.W. Rondorf, R.D. Garland, P.A. Verhey
2000, Transactions of the American Fisheries Society (129) 1389-1395
We tested the use of body morphology to distinguish among subyearling fall-run, subyearling spring-run, and yearling spring-run smolts of chinook salmon Oncorhynchus tshawytscha at two lower Snake River dams during the summer emigration. Based on principal-components analysis, subyearling fall-run chinook salmon had smaller heads and eyes, deeper bodies, and shorter...
Data report: Mid-Pliocene diatom assemblages at sites 1016, 1021, and 1022
John A. Barron
Susan Nessler, Christine M. Miller, Lori L. Peters, editor(s)
2000, Proceedings of the Ocean Drilling Program: Scientific Results 167-4
Diatom assemblages from the middle part of the Pliocene (3.2-2.5 Ma) were investigated from Ocean Drilling Program Sites 1016, 1021, and 1022 in an effort to infer paleotemperature fluctuations off California.<span face="Verdana, Arial, Helvetica, sans-serif" data-mce-style="font-family:...
Tracer transport in fractured crystalline rock: Evidence of nondiffusive breakthrough tailing
Matthew W. Becker, Allen M. Shapiro
2000, Water Resources Research (36) 1677-1686
Extended tailing of tracer breakthrough is often observed in pulse injection tracer tests conducted in fractured geologic media. This behavior has been attributed to diffusive exchange of tracer between mobile fluids traveling through channels in fractures and relatively stagnant fluid between fluid channels, along fracture walls, or within the bulk...
10,000 Years of explosive eruptions of Merapi Volcano, Central Java: archaeological and modern implications
C. G. Newhall, S. Bronto, B. Alloway, N.G. Banks, I. Bahar, Del Marmol, R.D. Hadisantono, R. T. Holcomb, J. McGeehin, J.N. Miksic, M. Rubin, S.D. Sayudi, R. Sukhyar, Supriyati Andreastuti, R.I. Tilling, R. Torley, D. Trimble, A.D. Wirakusumah
2000, Journal of Volcanology and Geothermal Research (100) 9-50
Stratigraphy and radiocarbon dating of pyroclastic deposits at Merapi Volcano, Central Java, reveals ~10,000 years of explosive eruptions. Highlights include: (1) Construction of an Old Merapi stratovolcano to the height of the present cone or slightly higher. Our oldest age for an explosive eruption is 9630±60 14C y B.P.; construction...
A modified ground-motion attenuation relationship for southern California that accounts for detailed site classification and a basin-depth effect
E. H. Field
2000, Bulletin of the Seismological Society of America (90) S209-S221
The attenuation relationship presented by Boore et al. (1997) has been evaluated and customized with respect to southern California strong-motion data (for peak ground acceleration (PGA) and 0.3-, 1.0-, and 3.0-sec period spectral acceleration). This study was motivated by the recent availability of a new site-classification map by Wills et...
Reconnaissance survey of sulfonamide, sulfonylurea, and imidazolinone herbicides in surface streams and groundwater of the Midwestern United States
T.R. Steinheimer, R.L. Pfeiffer, K.D. Scoggin, W.A. Battaglin
2000, Conference Paper, Agrochemical fate and movement
The study objective was to conduct a small scale synoptic survey of representative water resources draining agricultural land for occurrence of several herbicide residues. These new classes of herbicides are commonly applied pre-emergence or post-emergence in conservation tillage systems to control grasses and broadleaf weeds in cropped and noncropped areas....
Evaluation of toxicity: Whole-sediment versus overlying-water exposures with amphipod Hyalella azteca
C.G. Ingersoll, C.D. Ivey, E.L. Brunson, D.K. Hardesty, N.E. Kemble
2000, Environmental Toxicology and Chemistry (19) 2906-2910
A laboratory study was conducted to evaluate the toxicity of whole-sediment versus overlying-water exposures to the amphipod Hyalella azteca using field-collected sediments. Severe toxic effects (5-63% survival) were observed with amphipods exposed for 10 d in direct contact with sediment. In contrast, amphipods exposed only to overlying water in these...
Clast-fabric development in a shearing granular material: Implications for subglacial till and fault gouge
T.S. Hooyer, N.R. Iverson
2000, Geological Society of America Bulletin (112) 683-692
Elongate clasts in subglacial till and in fault gouge align during shearing, but the relation between clast-fabric strength and cumulative shear strain for such materials is effectively unknown. This relation was explored in experiments with a large ring-shear device in which a till and a viscous putty that contained isolated...
Photographic evaluation of the impacts of bottom fishing on benthic epifauna
J.S. Collie, G.A. Escanero, P. C. Valentine
2000, ICES Journal of Marine Science (57) 987-1001
The gravel sediment habitat on the northern edge of Georges Bank (East coast of North America) is an important nursery area for juvenile fish, and the site of a productive scallop fishery. During two cruises to this area in 1994 we made photographic transects at sites of varying depths that...
Observations of storm and river flood-driven sediment transport on the northern California continental shelf
A.S. Ogston, D.A. Cacchione, R.W. Sternberg, G.C. Kineke
2000, Continental Shelf Research (20) 2141-2162
In the winter of 1996-1997, three bottom-boundary layer tripods were placed in an alongshelf array on the northern California continental shelf off Eureka, CA in 60-65-m water depth. During the observation period, multiple storms and river discharge events occurred, as well as the largest flood on record since 1964. Suspended-sediment...
Rapid activation of gill Na+,K+-ATPase in the euryhaline teleost Fundulus heteroclitus
J. M. Mancera, S. D. McCormick
2000, Journal of Experimental Zoology (287) 263-274
The rapid activation of gill Na+,K+-ATPase was analyzed in the mummichog (Fundulus heteroclitus) and Atlantic salmon (Salmo salar) transferred from low salinity (0.1 ppt) to high salinity (25-35 ppt). In parr and presmolt, Salmo salar gill Na+,K+-ATPase activity started to increase 3 days after transfer. Exposure of Fundulus heteroclitus to...
Anisotropy of magnetic susceptibility as a tool for recognizing core deformation: Reevaluation of the paleomagnetic record of Pleistocene sediments from drill hole OL-92, Owens Lake, California
Joseph Rosenbaum, Richard L. Reynolds, Joseph Smoot, Robert Meyer
2000, Earth and Planetary Science Letters (178) 415-424
At Owens Lake, California, paleomagnetic data document the Matuyama/Brunhes polarity boundary near the bottom of a 323-m core (OL-92) and display numerous directional fluctuations throughout the Brunhes chron. Many of the intervals of high directional dispersion were previously interpreted to record magnetic excursions. For the upper ~120 m, these interpretations...
