Magnetic properties and emplacement of the Bishop tuff, California
H.C. Palmer, W.D. MacDonald, C. S. Grommé, B.B. Ellwood
1996, Bulletin of Volcanology (58) 101-116
Anisotropy of magnetic susceptibility (AMS) and characteristic remanence were measured for 45 sites in the 0.76 Ma Bishop tuff, eastern California. Thirty-three sites were sampled in three stratigraphic sections, two in Owens gorge south of Long Valley caldera, and the third in the Adobe lobe north of...
The southern Whidbey Island fault: An active structure in the Puget Lowland, Washington
S. Y. Johnson, C. J. Potter, J.M. Armentrout, J. J. Miller, Carol A. Finn, C.S. Weaver
1996, Geological Society of America Bulletin (108) 334-354
Information from seismic-reflection profiles, outcrops, boreholes, and potential field surveys is used to interpret the structure and history of the southern Whidbey Island fault in the Puget Lowland of western Washington. This northwest-trending fault comprises a broad (as wide as 6–11 km), steep, northeast-dipping zone that includes several splays with...
Three-dimensional crustal structure of the southern Sierra Nevada from seismic fan profiles and gravity modeling
M.M. Fliedner, S. Ruppert, P.E. Malin, S. K. Park, G. Jiracek, R. A. Phinney, J.B. Saleeby, B. Wernicke, R. Clayton, Rebecca Hylton Keller, K. Miller, C. Jones, J.H. Luetgert, Walter D. Mooney, H. Oliver, S.L. Klemperer, G. A. Thompson
1996, Geology (24) 367-370
Traveltime data from the 1993 Southern Sierra Nevada Continental Dynamics seismic refraction experiment reveal low crustal velocities in the southern Sierra Nevada and Basin and Range province of California (6.0 to 6.6 km/s), as well as low upper mantle velocities (7.6 to 7.8 km/s). The crust thickens from southeast to...
Southern Ocean monthly wave fields for austral winters 1985-1988 by Geosat radar altimeter
E.G. Josberger, N. M. Mognard
1996, Journal of Geophysical Research C: Oceans (101) 6689-6696
Four years of monthly averaged wave height fields for the austral winters 1985–1988 derived from the Geosat altimeter data show a spatial variability of the scale of 500–1000 km that varies monthly and annually. This variability is superimposed on the zonal patterns surrounding the Antarctic continent and characteristic of the...
Type of faulting and orientation of stress and strain as a function of space and time in Kilauea's south flank, Hawaii
D. Gillard, M. Wyss, P. Okubo
1996, Journal of Geophysical Research B: Solid Earth (101) 16025-16042
Earthquake focal mechanisms of events occurring between 1972 and 1992 in the south flank of Kilauea volcano, Hawaii, are used to infer the state of stress and strain as a function of time and space. We have determined 870 fault plane solutions from P wave first motion polarities for events with magnitudes ML ≥...
Block and shear-zone architecture of the Minnesota River Valley subprovince: Implications for late Archean accretionary tectonics
D. L. Southwick, V.W. Chandler
1996, Canadian Journal of Earth Sciences (33) 831-847
The Minnesota River Valley subprovince of the Superior Province is an Archean gneiss terrane composed internally of four crustal blocks bounded by three zones of east-northeast-trending linear geophysical anomalies. Two of the block-bounding zones are verified regional-scale shears. The geological nature of the third boundary has not been established. Potential-field...
Complete migration cycle of golden eagles breeding in northern Quebec
Serge Brodeur, R. DeCarie, D.M. Bird, Mark R. Fuller
1996, The Condor (98) 293-299
Radio tracking via satellite was initiated to study the year-round movements of Golden Eagles(Aquila chrysaetosc anadensis) breeding on the east coast of Hudson Bay, Quebec. In June and August 1992, six Golden Eagles(five adults and one juvenile) were marked, three of which completed their year-round movements. The eagles left their breeding area in mid-...
The stable oxygen and carbon isotopic record from a coral growing in Florida Bay: a 160 year record of climatic and anthropogenic influence
Peter K. Swart, Genevieve F. Healy, Richard E. Dodge, Philip Kramer, J. Harold Hudson, Robert B. Halley, Michael B. Robblee
1996, Palaeogeography, Palaeoclimatology, Palaeoecology (123) 219-237
A 160 year record of skeletal δ13C and δ18O was examined in a specimen of the coral Solenastrea bournonigrowing in Florida Bay. Variations in the δ18O of the skeleton can be correlated to changes in salinity while changes in the δ13C reflect cycling of organic material within the Bay. Based on...
Serological evidence of morbillivirus infection in polar bears (Ursus maritimus) from Alaska and Russia
Erich H. Follmann, G.W. Garner, Jim F. Evermann, McKeirnan
1996, Veterinary Record (138) 615-618
One-hundred-and-ninety-one samples of blood serum collected from 186 polar bears (Ursus maritimus) between 1987 and 1992 were analysed for morbillivirus antibodies. The samples were collected in the Bering, Chukchi and East Siberian seas. Sixty-eight samples (35.6 per cent) had morbillivirus antibody titres > 5; the percentage of positive samples ranged...
Climatic control of nitrate loss from forested watersheds in the northeast United States
M.J. Mitchell, C. T. Driscoll, J. S. Kahl, G.E. Likens, Peter S. Murdoch, L.H. Pardo
1996, Environmental Science & Technology (30) 2609-2612
Increased losses of nitrate from watersheds may accelerate the depletion of nutrient cations and affect the acidification and trophic status of surface waters. Patterns of nitrate concentrations and losses were evaluated in four forested watersheds (East Bear Brook Watershed, Lead Mountain, ME; Watershed 6, Hubbard Brook Experimental Forest, White Mountains,...
Directional topographic site response at Tarzana observed in aftershocks of the 1994 Northridge, California, earthquake: Implications for mainshock motions
P. Spudich, M. Hellweg, W.H.K. Lee
1996, Bulletin of the Seismological Society of America (86) S193-S208
The Northridge earthquake caused 1.78 g acceleration in the east-west direction at a site in Tarzana, California, located about 6 km south of the mainshock epicenter. The accelerograph was located atop a hill about 15-m high, 500-m long, and 130-m wide, striking about N78°E. During...
Sediment retention in a bottomland hardwood wetland in Eastern Arkansas
B.A. Kleiss
1996, Wetlands (16) 321-333
One of the often-stated functions of wetlands is their ability to remove sediments and other particulates from water, thus improving water quality in the adjacent aquatic system. However, actual rates of suspended sediment removal have rarely been measured in freshwater wetland systems. To address this issue, suspended sediment dynamics were...
Shear wave velocity structure in North America from large-scale waveform inversions of surface waves
D. Alsina, R.L. Woodward, R.K. Snieder
1996, Journal of Geophysical Research B: Solid Earth (101) 15969-15986
A two-step nonlinear and linear inversion is carried out to map the lateral heterogeneity beneath North America using surface wave data. The lateral resolution for most areas of the model is of the order of several hundred kilometers. The most obvious feature in the tomographic images is the rapid transition...
Origin of high mountains in the continents: The Southern Sierra Nevada
B. Wernicke, R. Clayton, Mihai N. Ducea, C.H. Jones, S. Park, S. Ruppert, J. Saleeby, J.K. Snow, L. Squires, M. Fliedner, G. Jiracek, Rebecca Hylton Keller, S. Klemperer, J. Luetgert, P. Malin, K. Miller, Walter D. Mooney, H. Oliver, R. Phinney
1996, Science (271) 190-193
Active and passive seismic experiments show that the southern Sierra, despite standing 1.8 to 2.8 kilometers above its surroundings, is underlain by crust of similar seismic thickness, about 30 to 40 kilometers. Thermobarometry of xenolith suites and magnetotelluric profiles indicate that the upper mantle is eclogitic to depths of 60...
Cambrian potential indicated in Kentucky Rome trough
David C. Harris, James A. Drahovzal
1996, Oil & Gas Journal (94) 52-57
A recent gas discovery in the Rome trough has Appalachian basin operators re-evaluating the deep Cambrian potential of eastern Kentucky. The Rome trough has seen sporadic exploration since the late 1940s, with very limited commercial success. A new exploration phase began in mid-1994 with completion of the Carson Associates 1...
Contrasts between Sm-Nd whole-rock and U-Pb zircon systematics in the Tobacco Root batholith, Montana: Implications for the determination of crustal age provinces
P.A. Mueller, A.L. Heatherington, K. A. D’Arcy, J. L. Wooden, A.P. Nutman
1996, Tectonophysics (265) 169-179
Proper documentation of the extent and age of crust in the western US is critical for constraining a variety of geologic problems ranging from the growth rate of continents to Precambrian continental reconstructions. The secondary isotopic systematics of granitoids have been one of the principal means used to characterize continental...
Geographic variation in migratory behavior of greater white-fronted geese (Anser albifrons)
Craig R. Ely, John Y. Takekawa
1996, The Auk (113) 889-901
We studied the migration and winter distribution of adult Greater White-fronted Geese (Anser albifrons frontalis) radio-marked on the Yukon-Kuskokwim Delta (YKD) and Bristol Bay Lowlands (BBL) of Alaska from 1987 to 1992. The major autumn staging site for geese from both breeding areas was the Klamath Basin on the California/Oregon...
Using hydrogeochemical methods to evaluate complex quaternary subsurface stratigraphy Block Island, Rhode Island, USA
A.I. Veeger, B. D. Stone
1996, Hydrogeology Journal (4) 69-82
One of the major problems in hydrogeologic investigations of glaciated regions is the determination of complex stratigraphic relationships in the subsurface where insufficient information is available from drilling and geophysical records. In this paper, chemical characteristics of groundwater were used to identify stratigraphic changes in glacial deposits that were previously...
Late Pennsylvanian climate changes and palynomorph extinctions
R.M. Kosanke, C. B. Cecil
1996, Review of Palaeobotany and Palynology (90) 113-140
A major floral change occurs in the Upper Pennsylvanian strata in the Midcontinent, Illinois basin, and in the northern Appalachian basin of eastern United States. Lycospora spp. (derived from arborescent lycopsids) became extinct along with some other palynomorph taxa. This investigation is concerned with the importance of this major floral...
Sea birds as proxies of marine habitats and food webs in the western Aleutian Arc
Alan M. Springer, John F. Piatt, Gus B. Van Vliet
1996, Fisheries Oceanography (5) 45-55
We propose that ocean conditions of the Near Islands in the western Aleutian Arc mimic those of the shallow continental shelf of the eastern Bering Sea to the extent that the marine community, including assemblages of forage fishes and their avian predators, has distinctly coastal characteristics. In contrast, marine avifauna...
The contribution of wetlands to stream nitrogen load in the Loch Vale Watershed, Colorado, USA
Huang Jian-hui, Jill Baron, Dan Binkley
1996, Chinese Journal of Plant Ecology (20) 289-302
We explored the difference between the concentrations of different N forms and other chemical properties between stream water and riparian zone wetland soil water in the Loch Vale Watershed which is located on the eastern slope of the Continental Divide in Rocky Mountain National Park, Colorado, USA. The nitrate N...
Sediment distribution on a storm-dominated insular shelf, Luquillo, Puerto Rico, U.S.A.
W. C. Schwab, R. W. Rodriguez, W.W. Danforth, M. H. Gowen
1996, Journal of Coastal Research (12) 147-159
A sea-floor mapping investigation designed to assess the sediment distribution, the movement of the nearshore sand supply, and the fate of sediment eroded from the shoreline was conducted using high-resolution sidescan-sonar, seismic reflection, and sediment sampling techniques on the northern insular shelf of Puerto Rico, off the town of Luquillo....
Transition from slab to slabless: Results from the 1993 Mendocino triple junction seismic experiment
B. C. Beaudoin, N. J. Godfrey, S.L. Klemperer, C. Lendl, A.M. Trehu, T.J. Henstock, A. Levander, J.E. Holl, A.S. Meltzer, James H. Luetgert, Walter D. Mooney
1996, Geology (24) 195-199
Three seismic refraction-reflection profiles, part of the Mendocino triple junction seismic experiment, allow us to compare and contrast crust and upper mantle of the North American margin before and after it is modified by passage of the Mendocino triple junction. Upper crustal velocity models reveal an asymmetric Great Valley basin...
Holocene paleoenvironments of Northeast Iowa
R. G. Baker, E. Arthur Bettis III, D. R. Schwert, D. G. Horton, C. A. Chumbley, Luis A. Gonzalez, M. K. Reagan
1996, Ecological Monographs (66) 203-234
This paper presents the biotic, sedimentary, geomorphic, and climatic history of the upper part of the Roberts Creek Basin, northeastern Iowa for the late—glacial and Holocene, and compares these records with a C—O isotopic sequence from Coldwater Cave, 60 km northwest of Roberts Creek. The biotic record (pollen, vascular plant...
Late Stage 5 Glacio-isostatic Sea in the St. Lawrence Valley, Canada and United States
S. Occhietti, S. Balescu, M. Lamothe, M. Clet, T. Cronin, P. Ferland, P. Pichet
1996, Quaternary Research (45) 128-137
Although post-glacial marine sediments of late Wisconsinan and early Holocene age are common in eastern Canada and the northeastern United States, remnants of older Pleistocene marine sediments are scarce. A fossiliferous marine clay that predates the classical Wisconsinan was recently discovered in the St. Lawrence Valley. A dominantly estuarine environment...
