Studies in neotropical paleobotany. XIV. A palynoflora from the middle Eocene Saramaguacán formation of Cuba
A. Graham, D. Cozadd, A. Areces-Mallea, N. O. Frederiksen
2000, American Journal of Botany (87) 1526-1539
An assemblage of 46 fossil pollen and spore types is described from a core drilled through the middle Eocene Saramaguacán Formation, Camagüey Province, eastern Cuba. Many of the specimens represent unidentified or extinct taxa but several can be identified to family (Palmae, Bombacaceae, Gramineae, Moraceae, Myrtaceae) and some to genus...
Rhyolite thermobarometry and the shallowing of the magma reservoir, Coso volcanic field, California
C.R. Manley, C. R. Bacon
2000, Journal of Petrology (41) 149-174
The compositionally bimodal Pleistocene Coso volcanic field is located at the western margin of the Basin and Range province ∼60 km north of the Garlock fault. Thirty-nine nearly aphyric high-silica rhyolite domes were emplaced in the past million years: one at 1 Ma from a transient magma reservoir, one...
Preliminary report on the 16 October 1999 M 7.1 Hector mine, California, earthquake
J. Behr, B. Bryant, D. Given, K. Gross, K. Hafner, J. Hardebeck, E. Hauksson, T. Heaton, S. Hough, K. Hudnut, K. Hutton, L. Jones, H. Kanamori, K. Kendrick, N. King, P. Maechling, A. Meltzner, D. Ponti, Thomas Rockwell, A. Shakal, M. Simons, K. Stark, D. Wald, L. Wald, L. Zhu
2000, Seismological Research Letters (71) 11-23
The Mw 7.1 Hector Mine, California, earthquake occurred at 9:46 GMT on 16 October 1999. The event caused minimal damage because it was located in a remote, sparsely populated part of the Mojave Desert, approximately 47 miles east-southeast of Barstow, with epicentral coordinates 34.59°N 116.27°W and a hypocentral...
Monitoring hydrilla using two RAPD procedures and the nonindigenous aquatic species database
Paul T. Madeira, C.C. Jacono, Thai K. Van
2000, Journal of Aquatic Plant Management (38) 33-40
Hydrilla (Hydrilla verticillata (L.f.) Royle), an invasive aquatic weed, continues to spread to new regions in the United States. Two biotypes, one a female dioecious and the other monoecious have been identified. Management of the spread of hydrilla requires understanding the mechanisms of introduction and transport, an ability to map...
The Midway sequence: A Timiskaming-type, pull-apart basin deposit in the western Wawa subprovince, Minnesota
M.A. Jirsa
2000, Canadian Journal of Earth Sciences (37) 1-15
The Midway sequence is an assemblage of subaerially deposited clastic and volcanic rocks that forms a narrow wedge within Neoarchean greenstone of the western Wawa subprovince of the Superior Province. Volcanic conglomerate in the Midway sequence contains clasts of stratigraphically older greenstone, together with clasts of a distinctive hornblende-phyric trachyandesite...
Interaction of infection with Renibacterium salmoninarum and physical stress in juvenile chinook salmon: Physiological responses, disease progression, and mortality
M.G. Mesa, A.G. Maule, C.B. Schreck
2000, Transactions of the American Fisheries Society (129) 158-173
We experimentally infected juvenile spring chinook salmon Oncorhynchus tshawytscha with Renibacterium salmoninarum (Rs), the causative agent of bacterial kidney disease (BKD), in order to compare the physiological responses of Rs-infected and Rs-noninfected fish to a series of multiple, acute stressors and to determine whether exposure to these stressors worsens the...
Modeling biotic habitat high risk areas
Don G. Despain, P. Beier, C. Tate, B.M. Durtsche, T. Stephens
2000, Journal of Sustainable Forestry (11) 89-117
Fire, especially stand replacing fire, poses a threat to many threatened and endangered species as well as their habitat. On the other hand, fire is important in maintaining a variety of successional stages that can be important for approach risk assessment to assist in prioritizing areas for allocation of fire...
High-resolution seismic reflection surveys and modeling across an area of high damage from the 1994 Northridge earthquake, Sherman Oaks, California
William J. Stephenson, Robert A. Williams, Jack K. Odum, David M. Worley
2000, Bulletin of the Seismological Society of America (90) 643-654
Approximately 3.6 km of P-wave seismic-reflection data were acquired along two orthogonal profiles in Sherman Oaks, California to determine whether shallow (less than 1-km depth) geologic structures contributed to the dramatic localized damage resulting from the 1994 Northridge earthquake. Both lines, one along Matilija Avenue and one along Milbank Street,...
Gas content and composition of gas hydrate from sediments of the southeastern North American continental margin
T.D. Lorenson, T. S. Collett
2000, Conference Paper, Proceedings of the Ocean Drilling Program: Scientific Results
Gas hydrate samples were recovered from four sites (Sites 994, 995, 996, and 997) along the crest of the Blake Ridge during Ocean Drilling Program (ODP) Leg 164. At Site 996, an area of active gas venting, pockmarks, and chemosynthetic communities, vein-like gas hydrate was recovered from less than 1...
Modeling sand bank formation around tidal headlands
Richard P. Signell, Courtney K. Harris
2000, Proceedings of the International Conference on Estuarine and Coastal Modeling 209-222
Sandbanks are often found in the vicinity of coastal headlands around which tidal flows are strong enough to generate significant tidally-forced residual eddies, typically with scales of 2-10 km. One popular hypothesis is that these sandbanks are generated by a 'tidal stirring' mechanism in which the inward-directed pressure gradient associated...
Environmental contaminants in Texas, USA, wetland reptiles: Evaluation using blood samples
D. R. Clark Jr., J. W. Bickham, D.L. Baker, D.F. Cowman
2000, Environmental Toxicology and Chemistry (19) 2259-2265
Four species of reptiles (diamondback water snake [Nerodia rhombifer], blotched water snake [N. erythrogaster], cottonmouth [Agkistrodon piscivorus], and red-eared slider [Trachemys scripta]) were collected at two contaminated and three reference sites in Texas, USA. Old River Slough has received intensive applications of agricultural chemicals since the 1950s. Municipal Lake received...
Evidence for a previously unrecognized species of owlet-nightjar
T.K. Pratt
2000, The Auk (117) 1-11
I studied the systematic relationships of the three large owlet-nightjars (Aegothelidae) to determine the taxonomic status of a fawn-colored lowland form currently classified as Aegotheles insignis tatei. I examined most of the existing specimens of A. i. insignis (n = 158) and A. crinifrons (n = 23) and all known...
Sediment-contact and survival of fingernail clams: Implications for conducting short-term laboratory tests
T.J. Naimo, W.G. Cope, M.R. Bartsch
2000, Environmental Toxicology (15) 23-27
Porewater toxicity tests have been used as indicators of whole sediment toxicity. However, many species commonly tested in porewater predominately reside in the water column and otherwise have little to no direct contact with sediment and associated porewater. We assessed the feasibility of porewater toxicity tests with fingernail clams Musculium...
Pesticides in wells in agricultural and urban areas of the Hudson River basin
P. J. Phillips, G. R. Wall, C.M. Ryan
2000, Northeastern Geology and Environmental Sciences (22) 1-9
Ground-water samples from four monitoring well networks in the Hudson River basin were analyzed for pesticides (detection limits from 0.001 to 0.018 ??g/L). The most frequent detections were in samples from shallow depths beneath agricultural areas. Concentrations of pesticides in samples from all four networks were generally below 0.10 ??g/L,...
Intra- and inter-unit variation in fly ash petrography and mercury adsorption: Examples from a western Kentucky power station
J.C. Hower, R. B. Finkelman, R.F. Rathbone, J. Goodman
2000, Energy and Fuels (14) 212-216
Fly ash was collected from eight mechanical and 10 baghouse hoppers at each of the twin 150-MW wall-fired units in a western Kentucky power station. The fuel burned at that time was a blend of many low-sulfur, high-volatile bituminous Central Appalachian coals. The baghouse ash showed less variation between units...
Vegetation associations in a rare community type - Coastal tallgrass prairie
James B. Grace, Larry K. Allain, Charles Allen
2000, Plant Ecology (147) 105-115
The coastal prairie ecoregion is located along the northwestern coastal plain of the Gulf of Mexico in North America. Because of agricultural and urban development, less than 1% of the original 3.4 million ha of this ecosystem type remains in native condition, making it one of the most endangered ecosystems...
Characterizing multiple timescales of stream and storage zone interaction that affect solute fate and transport in streams
Jungyill Choi, Judson W. Harvey, Martha H. Conklin
2000, Water Resources Research (36) 1511-1518
The fate of contaminants in streams and rivers is affected by exchange and biogeochemical transformation in slowly moving or stagnant flow zones that interact with rapid flow in the main channel. In a typical stream, there are multiple types of slowly moving flow zones in which exchange and transformation occur,...
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...
Testing methods to produce landscape-scale presettlement vegetation maps from the U.S. public land survey records
K.L. Manies, D.J. Mladenoff
2000, Landscape Ecology (15) 741-754
The U.S. Public Land Survey (PLS) notebooks are one of the best records of the pre-European settlement landscape and are widely used to recreate presettlement vegetation maps. The purpose of this study was to evaluate the relative ability of several interpolation techniques to map this vegetation, as sampled by the...
Water quality degradation effects on freshwater availability: Impacts of human activities
Norman E. Peters, Michel Meybeck
2000, Water International (25) 185-193
The quality of freshwater at any point on the landscape reflects the combined effects of many processes along water pathways. Human activities on all spatial scales affect both water quality and quantity. Alteration of the landscape and associated vegetation has not only changed the water balance, but typically has altered...
Effects of a spring flushing flow on the distribution of radio-tagged juvenile rainbow trout in a Wyoming tailwater
D.G. Simpkins, W.A. Hubert, Thomas A. Wesche
2000, North American Journal of Fisheries Management (20) 546-551
The controlled release of dammed water, designed to produce a flushing flow that would remove fine sediments from spawning habitat in a flow-regulated river, did not displace juvenile rainbow trout Oncorhynchus mykiss (20-25 cm total length) downstream. Of eight naturally spawned (wild) and nine hatchery fish that were radio-tagged, only...
Katmai volcanic cluster and the great eruption of 1912
W. Hildreth, J. Fierstein
2000, Geological Society of America Bulletin (112) 1594-1620
In June 1912, the world's largest twentieth century eruption broke out through flat-lying sedimentary rocks of Jurassic age near the base of Trident volcano on the Alaska Peninsula. The 60 h ash-flow and Plinian eruptive sequence excavated and subsequently backfilled with ejecta a flaring funnel-shaped vent since called Novarupta. The...
Carbon dioxide from coal combustion: Variation with rank of US coal
J.C. Quick, D.C. Glick
2000, Fuel (79) 803-812
Carbon dioxide from combustion of US coal systematically varies with ASTM rank indices, allowing the amount of CO2 produced per net unit of energy to be predicted for individual coals. No single predictive equation is applicable to all coals. Accordingly, we provide one equation for coals above high volatile bituminous...
Fish remains from Homestead Cave and lake levels of the past 13,000 years in the Bonneville basin
J.M. Broughton, D.B. Madsen, Jay Quade
2000, Quaternary Research (53) 392-401
A late Quaternary ichthyofauna from Homestead Cave, Utah, provides a new source of information on lake history in the Bonneville basin. The fish, represented by 11 freshwater species, were accumulated between ~11,200 and ~1000 14C yr B.P. by scavenging owls. The 87Sr/86Sr ratio of Lake Bonneville varied with its elevation;...
Stable isotope systematics of sulfate minerals
Robert R. Seal II, Charles N. Alpers, Robert O. Rye
2000, Reviews in Mineralogy and Geochemistry (40) 541-602
Stable isotope studies of sulfate minerals are especially useful for unraveling the geochemical history of geological systems. All sulfate minerals can yield sulfur and oxygen isotope data. Hydrous sulfate minerals, such as gypsum, also yield oxygen and hydrogen isotope data for the water of hydration, and more complex sulfate minerals,...
