Day one road log: Mid-Tertiary igneous rocks and mineral deposits in the central Wasatch Mountains, Utah
David A. John
1997, Society of Economic Geologists guidebook series (29) 59-67
Today's field trip examines late Eocene and Oligocene granitoid intrusions, cogenetic volcanic rocks (Keetley Volcanics), and associated hydrothermally altered and mineralized rocks in the central Wasatch Mountains. Because of late Cenozoic tilting related to Basin and Range extension, a continuum of mid-Tertiary paleodepths is exposed that ranges from about 11...
Synthesis of the paleoclimatic record from Owens Lake core OL-92
George I. Smith, James L. Bischoff, J. Platt Bradbury
1997, Book chapter, An 800,000-year paleoclimatic record from core OL-92, Owens Lake, Southeast California
During much of the late Quaternary, Owens Lake overflowed into one or more of four successively lower-elevation basins. Most of the water came from the high, eastern slopes of the southern Sierra Nevada, and changes in the volumes of that water reflect a dominant climatic cycle of ~100 k.y. Variations...
An 800,000-year pollen record from Owens Lake, California: Preliminary analyses
Ronald J. Litwin, D.P. Adam, N. O. Frederiksen, W. B. Woolfenden
1997, Book chapter, An 800,000-year paleoclimatic record from core OL-92, Owens Lake, Southeast California
A long sequence of fossil palynomorph assemblages from a 323-m-long core taken at Owens Lake has enabled us to evaluate the gross vegetational trends for the Owens Valley region of California over the past ~800,000 years. Shifts in vegetation composition and abundance in the study area during the Pleistocene were...
The Spruce Head composite pluton: An example of mafic to silicic Salinian magmatism in coastal Maine, northern Appalachians
Robert A. Ayuso, Joseph G. Arth
1997, Book chapter, The nature of magmatism in the Appalachian orogen
No abstract available....
Stratigraphy, lithologies, and sedimentary structures of Owens Lake core OL-92
George I. Smith
George I. Smith, James L. Bischoff, editor(s)
1997, Book chapter, An 800,000-year paleoclimatic record from core OL-92, Owens Lake, Southeast California
Owens Lake, a now-dry lake in southeastern California immediately east of the southern Sierra Nevada, was the site of a coring project designed to obtain a long paleoclimatic record. During the ensuing study, lacustrine deposits were recovered by the 323 m long core designated “OL-92.” The presence of the Bishop...
Level II scour analysis for Bridge 16, (NEWBTH00500016) on Town Highway 50, crossing Halls Brook, Newbury, Vermont
Ronda L. Burns, James R. Degnan
1997, Open-File Report 97-814
This report provides the results of a detailed Level II analysis of scour potential at structure NEWBTH00500016 on Town Highway 50 crossing Halls Brook, Newbury, Vermont (figures 1–8). A Level II study is a basic engineering analysis of the site, including a quantitative analysis of stream stability and scour (U.S....
Contaminant exposure, biochemical, and histopathological biomarkers in white suckers from contaminated and reference sites in the Sheboygan River, Wisconsin
C.S. Schrank, S.M. Cormier, V. S. Blazer
1997, Journal of Great Lakes Research (23) 119-130
Fish populations of the lower Sheboygan River, located in east-central Wisconsin, are considered impaired under the Great Lakes Water Quality Agreement between the United States and Canada. Pollutants in the Sheboygan River system include: polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs),...
Nested taxa-area curves for eastern United States floras
J. P. Bennett
1997, Rhodora (99) 241-251
The slopes of log-log species-area curves have been studied extensively and found to be influenced by the range of areas under study. Two such studies of eastern United States floras have yielded species-area curve slopes which differ by more than 100%: 0.251 and 0.113. The first slope may be too...
Changes in breeding bird populations in North Dakota: 1967 to 1992-93
L.D. Igl, Douglas H. Johnson
1997, The Auk (114) 74-92
We compared breeding bird populations in North Dakota using surveys conducted in 1967 and 1992-93. In decreasing order, the five most frequently occurring species were Horned Lark (Eremophila alpestris), Brown-headed Cowbird (Molothrus ater), Western Meadowlark (Sturnella neglecta), Red-winged Blackbird (Agelaius phoeniceus), and Eastern Kingbird (Tyrannus tyrannus). The five most abundant...
Small mammal community composition in cornfields, roadside ditches, and prairies in eastern Nebraska
E.M. Kirsch
1997, Natural Areas Journal (17) 204-211
Community composition of small mammals was examined in prairies, cornfields, and their adjacent roadside ditches in eastern Nebraska. Western harvest mice (Reithrodontomys megalotis) and meadow voles (Microtus pennsylvanicus) were associated with prairie habitat, were common in ditches, but avoided cornfields. Prairie voles (M. Ochrogaster) and white-footed mice (Peromyscus leucopus) were...
Imperfect science: Uncertainty, diversity, and experts
Thomas C. Hanks
1997, Eos, Transactions, American Geophysical Union (78) 369-377
Seismic safety issues related to nuclear reactors in the eastern United States pose special challenges to the Earth and engineering sciences, given the severe consequences that can attend even very infrequent earthquakes. To deal with low-probability, potentially damaging ground motions, two major probabilistic seismic hazard analyses...
Description and epizootiology of Babesia poelea n. sp. in brown boobies (Sula leucogaster (Boddaert)) on Sand Island, Johnston Atoll, Central Pacific
Thierry M. Work, Robert Rameyer
1997, Journal of Parasitology (83) 734-738
We describe a new species of piroplasm from brown boobies (Sula leucogaster) on Sand Island, Johnston Atoll National Wildlife Refuge, central Pacific. Mean parasitemia in adults and chicks was less than 1%, with the parasitemia in chicks significantly greater than in adults. There was no significant relation between the age...
NDVI, C3 and C4 production, and distributions in Great Plains grassland land cover classes
L.L. Tieszen, Bradley C. Reed, Norman B. Bliss, Bruce K. Wylie, Benjamin D. DeJong
1997, Ecological Applications (7) 59-78
The distributions of C3 and C4 grasses were used to interpret the distribution, seasonal performance, and potential production of grasslands in the Great Plains of North America. Thirteen major grassland seasonal land cover classes were studied with data from three distinct sources. Normalized Difference Vegetation Index (NDVI) data derived from...
Progressive deformation of the Chugach accretionary complex, Alaska, during a paleogene ridge-trench encounter
Timothy M. Kusky
1997, Journal of Structural Geology (19) 139-157
The Mesozoic accretionary wedge of south-central Alaska is cut by an array of faults including dextral and sinistral strike-slip faults, synthetic and antithetic thrust faults, and synthetic and antithetic normal faults. The three fault sets are characterized by quartz ± calcite ± chlorite ± prehnite slickensides, and are all relatively...
Correlation of Upper Cretaceous strata from Lima Peaks area to Madison Range, southwestern Montana and southeastern Idaho, USA
T. S. Dyman, R. G. Tysdal, W. J. Perry Jr., J. D. Obradovich, J. C. Haley, D. J. Nichols
1997, Cretaceous Research (18) 751-766
An40Ar/39Ar age of 85.81 Ma±0.22 my was obtained on sanidine from a volcanic procellanite bed near the top of the 2135+m-thick Upper Cretaceous Frontier Formation in the Lima Peaks area of southwestern Montana. This early Santonian age, combined with previously determined age data including a palynological age of Cenomanian for...
Hazard assessment of inorganics, individually and in mixtures, to two endangered fish in the San Juan River, New Mexico
Steven J. Hamilton, Kevin J. Buhl
1997, Environmental Toxicology (12) 195-209
Acute toxicity tests were conducted for 96 h with larval Colorado squawfish (Ptychocheilus lucius) and razorback sucker (Xyrauchen texanus) in a reconstituted water quality simulating the San Juan River near Shiprock, New Mexico, to determine biological effect concentrations. Tests were conducted with arsenate, copper, selenate, selenite, zinc, and five mixtures...
Field guide to the Mesozoic accretionary complex along Turnagain Arm and Kachemak Bay, south-central Alaska
Dwight Bradley, Timothy M. Kusky, Susan M. Karl, Peter J. Haeussler
1997, Book chapter, 1997 Guide to the geology of the Kenai Peninsula. Alaska
Turnagain Arm, just east of Anchorage, provides a readily accessible, world-class cross section through a Mesozoic accretionary wedge. Nearly continuous exposures along the Seward Highway, the Alaska Railroad, and the shoreline of Turnagain Arm display the two main constituent units of the Chugach terrane: the McHugh Complex and Valdez Group....
Variable deep structure of a midcontinent fault and fold zone from seismic reflection: La Salle deformation belt, Illinois basin
J.H. McBride
1997, Geological Society of America Bulletin (109) 1502-1513
Deformation within the United States midcontinent is frequently expressed as quasilinear zones of faulting and folding, such as the La Salle deformation belt, a northwest-trending series of folds cutting through the center of the Illinois basin. Seismic reflection profiles over the southern La...
Massive sediment bypassing on the lower shoreface offshore of a wide tidal inlet: Cat Island Pass, Louisiana
B. E. Jaffe, J. H. List, A. H. Sallenger Jr.
1997, Marine Geology (136) 131-149
Analysis of a series of historical bathymetric and shoreline surveys along the Louisiana coast west of the Mississippi River mouth detected a large area of deposition in water depths of 2.0–8.5 m offshore of a 9-km-wide tidal inlet, the Cat Island Pass/Wine Island Pass system. A 59.9 · 106 m3 sandy...
Rapid extension in an Eocene volcanic arc: Structure and paleogeography of an intra-arc half graben in central Idaho
S. U. Janecke, B.F. Hammond, L.W. Snee, J. W. Geissman
1997, Geological Society of America Bulletin (109) 253-267
A study of extension, volcanism, and sedimentation in the middle Eocene Panther Creek half graben in central Idaho shows that it formed rapidly during an episode of voluminous volcanism. The east-southeast-tilted Panther Creek half graben developed across the northeast edge of the largest cauldron complex of the Challis volcanic field...
Late Cenozoic history and slip rates of the Fish Lake Valley, Emigrant Peak, and Deep Springs fault zones, Nevada and California
M.C. Reheis, T. L. Sawyer
1997, Geological Society of America Bulletin (109) 280-299
Several well-dated stratigraphic markers permit detailed assessment of the temporal and spatial variation in slip rates along the interconnected faults of the Fish Lake Valley, Emigrant Peak, and Deep Springs fault zones in west-central Nevada and east-central California. Right-lateral motion on the Fish Lake Valley fault zone apparently began ca....
14C ages and activity for the past 50 ka at Volcán Galeras, Colombia
N.G. Banks, V.M.L. Calvache, S.N. Williams
1997, Journal of Volcanology and Geothermal Research (77) 39-55
Volcán Galeras is the southernmost Colombian volcano with well-recorded historic activity. The volcano is part of a large and complex volcanic center upon which 400,000 people live. Historic activity has centered on a small-volume cone inside the youngest of several large amphitheaters that breach the west flank of the volcano,...
The Chesapeake Bay bolide impact: A convulsive event in Atlantic Coastal Plain evolution
C. Wylie Poag
1997, Sedimentary Geology (108) 45-90
Until recently, Cenozoic evolution of the Atlantic Coastal Plain has been viewed as a subcyclical continuum of deposition and erosion. Marine transgressions alternated with regressions on a slowly subsiding passive continental margin, their orderly succession modified mainly by isostatic adjustments, occasional Appalachian tectonism, and paleoclimatic change. This passive scenario was...
Primitive magmas at five Cascade volcanic fields: Melts from hot, heterogeneous sub-arc mantle
C. R. Bacon, P. E. Bruggman, R.L. Christiansen, M.A. Clynne, J.M. Donnelly-Nolan, W. Hildreth
1997, Canadian Mineralogist (35) 397-423
Major and trace element concentrations, including REE by isotope dilution, and Sr, Nd, Pb, and O isotope ratios have been determined for 38 mafic lavas from the Mount Adams, Crater Lake, Mount Shasta, Medicine Lake, and Lassen volcanic fields, in the Cascade arc, northwestern part of the United States. Many...
Rift-wide correlation of 1.1 Ga Midcontinent rift system basalts: Implications for multiple mantle sources during rift development
S. W. Nicholson, S.B. Shirey, K. J. Schulz, J.C. Green
1997, Canadian Journal of Earth Sciences (34) 504-520
Magmatism that accompanied the 1.1 Ga Midcontinent rift system (MRS) is attributed to the upwelling and decompression melting of a mantle plume beneath North America. Five distinctive flood-basalt compositions are recognized in the rift-related basalt succession along the south shore of western Lake Superior, based on stratigraphically correlated major element, trace...
