Seismic hazard maps of Mexico, the Caribbean, and Central and South America
J.G. Tanner, K. M. Shedlock
2004, Tectonophysics (390) 159-175
The growth of megacities in seismically active regions around the world often includes the construction of seismically unsafe buildings and infrastructures due to an insufficient knowledge of existing seismic hazard and/or economic constraints. Minimization of the loss of life, property damage, and social and economic disruption due to earthquakes depends...
VOCs in shallow groundwater in new residential/commercial areas of the United States
P. J. Squillace, M.J. Moran, C. V. Price
2004, Environmental Science & Technology (38) 5327-5338
The quality of shallow groundwater in urban areas was investigated by sampling 518 monitoring wells between 1996 and 2002 as part of the National Water-Quality Assessment Program of the U.S. Geological Survey. Well networks were installed primarily in new residential/commercial areas less than about 30 years old (17 studies) and...
Ground water chlorinated ethenes in tree trunks: Case studies, influence of recharge, and potential degradation mechanism
D.A. Vroblesky, B.D. Clinton, J.M. Vose, C.C. Casey, G. J. Harvey, P. M. Bradley
2004, Ground Water Monitoring and Remediation (24) 124-138
Trichloroethene (TCE) was detected in cores of trees growing above TCE-contaminated ground at three sites: the Carswell Golf Course in Texas, Air Force Plant PJKS in Colorado, and Naval Weapons Station Charleston in South Carolina. This was true even when the depth to water was 7.9 m or when the...
Wrightwood and the earthquake cycle: What a long recurrence record tells us about how faults work
R. Weldon, K. Scharer, T. Fumal, G. Biasi
2004, GSA Today (14) 4-10
The concept of the earthquake cycle is so well established that one often hears statements in the popular media like, "the Big One is overdue" and "the longer it waits, the bigger it will be." Surprisingly, data to critically test the variability in recurrence intervals, rupture displacements, and relationships between...
Evaluation of multidimensional transport through a field-scale compacted soil liner
T.W. Willingham, C.J. Werth, A.J. Valocchi, I.G. Krapac, C. Toupiol, T.D. Stark, D.E. Daniel
2004, Journal of Geotechnical and Geoenvironmental Engineering (130) 887-895
A field-scale compacted soil liner was constructed at the University of Illinois at Urbana-Champaign by the U.S. Environmental Protection Agency (USEPA) and Illinois State Geological Survey in 1988 to investigate chemical transport rates through low permeability compacted clay liners (CCLs). Four tracers (bromide and three benzoic acid tracers) were each...
Garnet lherzolites from Louwrensia, Namibia: Bulk composition and P/T relations
F.R. Boyd, D.G. Pearson, Karin O. Hoal, B.G. Hoal, P.H. Nixon, M.J. Kingston, S.A. Mertzman
2004, LITHOS (77) 573-592
Bulk, mineral and trace element analyses of garnet lherzolite xenoliths from the Louwrensia kimberlite pipe, south-central Namibia, together with previously published Re-Os isotopic data [Chem. Geol. (2004)], form the most extensive set of chemical data for off-craton suites from southern Africa. The Louwrensia suite is similar to those from the...
Aquifers of the Denver Basin, Colorado
R. Topper
2004, Mountain Geologist (41) 145-152
Development of the Denver Basin for water supply has been ongoing since the late 1800s. The Denver Basin aquifer system consists of the water-yielding strata of Tertiary and Cretaceous sedimentary rocks within four overlying formations. The four statutory aquifers contained in these formations are named the Dawson, Denver, Arapahoe, and...
Has the conversion of natural wetlands to agricultural land increased the incidence and severity of damaging freezes in south Florida?
C. H. Marshall, R.A. Pielke Sr., L. T. Steyaert
2004, Monthly Weather Review (132) 2243-2258
On several occasions, winter freezes have wrought severe destruction on Florida agriculture. A series of devastating freezes around the turn of the twentieth century, and again during the 1980s, were related to anomalies in the large-scale flow of the ocean–atmosphere system. During the twentieth century, substantial areas of wetlands in...
Mesoscale spatial variability of selected aquatic invertebrate community metrics from a minimally impaired stream segment
J.B. Gebler
2004, Journal of the North American Benthological Society (23) 616-633
The related topics of spatial variability of aquatic invertebrate community metrics, implications of spatial patterns of metric values to distributions of aquatic invertebrate communities, and ramifications of natural variability to the detection of human perturbations were investigated. Four metrics commonly used for stream assessment were computed for 9 stream reaches...
Habitat use and spatial structure of a barking frog (Eleutherodactylus augusti) population in southeastern Arizona
C.S. Goldberg, C.R. Schwalbe
2004, Journal of Herpetology (38) 305-312
Barking Frogs (Eleutherodactylus augusti) are the northernmost ranging member of the large tropical family Leptodactylidae. We investigated the ecology of this saxicolous species at the northern edge of its range in a canyon in southern Arizona. We captured 54 frogs on discontinuous rock outcrops; eight of nine females and 39...
Natural selection of the major histocompatibility complex (Mhc) in Hawaiian honeycreepers (Drepanidinae)
S.I. Jarvi, C.L. Tarr, C.E. Mcintosh, C. T. Atkinson, R.C. Fleischer
2004, Molecular Ecology (13) 2157-2168
The native Hawaiian honeycreepers represent a classic example of adaptive radiation and speciation, but currently face one the highest extinction rates in the world. Although multiple factors have likely influenced the fate of Hawaiian birds, the relatively recent introduction of avian malaria is thought to be a major factor limiting...
Evidence for competitive dominance of Pink salmon (Oncorhynchus gorbuscha) over other Salmonids in the North Pacific Ocean
G.T. Ruggerone, J.L. Nielsen
2004, Reviews in Fish Biology and Fisheries (14) 371-390
Relatively little is known about fish species interactions in offshore areas of the world's oceans because adequate experimental controls are typically unavailable in such vast areas. However, pink salmon (Oncorhynchus gorbuscha) are numerous and have an alternating-year pattern of abundance that provides a natural experimental control to test for interspecific...
Predicting patterns of non-native plant invasions in Yosemite National Park, California, USA
E.C. Underwood, R. Klinger, P.E. Moore
2004, Diversity and Distributions (10) 447-459
One of the major issues confronting management of parks and reserves is the invasion of non-native plant species. Yosemite National Park is one of the largest and best-known parks in the United States, harbouring significant cultural and ecological resources. Effective management of non-natives would be greatly assisted by information on...
Use of an electromagnetic seepage meter to investigate temporal variability in lake seepage
D.O. Rosenberry, R. H. Morin
2004, Ground Water (42) 68-77
A commercially available electromagnetic flowmeter is attached to a seepage cylinder to create an electromagnetic seepage meter (ESM) for automating measurement of fluxes across the sediment/water interface between ground water and surface water. The ESM is evaluated through its application at two lakes in New England, one where water seeps...
Early Tertiary Anaconda metamorphic core complex, southwestern Montana
J.M. O’Neill, J. D. Lonn, D. R. Lageson, Michael J. Kunk
2004, Canadian Journal of Earth Sciences (41) 63-72
A sinuous zone of gently southeast-dipping low-angle Tertiary normal faults is exposed for 100 km along the eastern margins of the Anaconda and Flint Creek ranges in southwest Montana. Faults in the zone variously place Mesoproterozoic through Paleozoic sedimentary rocks on younger Tertiary granitic rocks or on sedimentary rocks older...
The effects of habitat resolution on models of avian diversity and distributions: A comparison of two land-cover classifications
Joshua J. Lawler, Raymond. J. O’Connor, Carolyn T. Hunsaker, K. Bruce Jones, Thomas R. Loveland, Denis White
2004, Landscape Ecology (19) 517-532
Quantifying patterns is a key element of landscape analysis. One aspect of this quantification of particular importance to landscape ecologists is the classification of continuous variables to produce categorical variables such as land-cover type or elevation stratum. Although landscape ecologists are fully aware of the importance of spatial resolution in...
Losses to single-family housing from ground motions in the 1994 Northridge, California, earthquake
R. L. Wesson, D. M. Perkins, E. V. Leyendecker, R.J. Roth Jr., M.D. Petersen
2004, Earthquake Spectra (20) 1021-1045
The distributions of insured losses to single-family housing following the 1994 Northridge, California, earthquake for 234 ZIP codes can be satisfactorily modeled with gamma distributions. Regressions of the parameters in the gamma distribution on estimates of ground motion, derived from ShakeMap estimates or from interpolated observations, provide a basis for...
Relatedness and nesting dispersion within breeding populations of Greater White-fronted Geese
A. C. Fowler, J.M. Eadie, Craig R. Ely
2004, Condor (106) 600-607
We studied patterns of relatedness and nesting dispersion in female Pacific Greater White-fronted Geese (Anser albifrons frontalis) in Alaska. Female Greater White-fronted Geese are thought to be strongly philopatric and are often observed nesting in close association with other females. Analysis of the distribution of nests on the Yukon-Kuskokwim Delta...
Improved spatial resolution for U-series dating of opal at Yucca Mountain, Nevada, USA, using ion-microprobe and microdigestion methods
J.B. Paces, L.A. Neymark, J. L. Wooden, H.M. Persing
2004, Geochimica et Cosmochimica Acta (68) 1591-1606
Two novel methods of in situ isotope analysis, ion microprobe and microdigestion, were used for 230Th/U and 234U/238U dating of finely laminated opal hemispheres formed in unsaturated felsic tuff at Yucca Mountain, Nevada, proposed site for a high-level radioactive waste repository. Both methods allow analysis of layers as many as...
Occurrence, size, and tag retention of sneaker male hatchery rainbow trout
J. Jeffery Isely, T.B. Grabowski
2004, North American Journal of Aquaculture (66) 234-236
One alternative reproductive tactic involving early-maturing, cryptic males is referred to as "sneaking." Although sneakers tend to be easily detectable upon close inspection, little is known about the proportion of a fish population consisting of sneakers. We examined 15,400 age-1 rainbow trout Oncorhynchus mykiss in a hatchery. Total length (mm),...
Degradates provide insight to spatial and temporal trends of herbicides in ground water
D.W. Kolpin, D.J. Schnoebelen, E.M. Thurman
2004, Groundwater (42) 601-608
Since 1995, a network of municipal wells in Iowa, representing all major aquifer types (alluvial, bedrock/karst region, glacial drift, bedrock/nonkarst region), has been repeatedly sampled for a broad suite of herbicide compounds yielding one of the most comprehensive statewide databases of such compounds currently available in the United States. This...
Evaluation of cage micro-environment of mice housed on various types of bedding materials
E. Smith, J.D. Stockwell, I. Schweitzer, S.H. Langley, A. L. Smith
2004, Contemporary Topics in Laboratory Animal Science (43) 12-17
A variety of environmental factors can affect the outcomes of studies using laboratory rodents. One such factor is bedding. Several new bedding materials and processing methods have been introduced to the market in recent years, but there are few reports of their performance. In the studies reported here, we have...
Pedogenic silica accumulation in chronosequence soils, southern California
K.J. Kendrick, R.C. Graham
2004, Soil Science Society of America Journal (68) 1295-1303
Chronosequential analysis of soil properties has proven to be a valuable approach for estimating ages of geomorphic surfaces where no independent age control exists. In this study we examined pedogenic silica as an indicator of relative ages of soils and geomorphic surfaces, and assessed potential sources of the silica. Pedogenic...
Goals and strategies for estimating trends in landbird abundance
J. Bart, K.P. Burnham, Erica H. Dunn, C.M. Francis, Ralph C. John
2004, Journal of Wildlife Management (68) 611-626
Reliable estimates of trends in population size are critical to effective management of landbirds. We propose a standard for considering that landbird populations are adequately monitored: 80% power to detect a 50% decline occuning within 20 years, using a 2-tailed test and a significance level of 0.10, and incorporating effects...
Gas-partitioning tracer test to quantify trapped gas during recharge
V.M. Heilweil, D. K. Solomon, K. S. Perkins, K. M. Ellett
2004, Ground Water (42) 589-600
Dissolved helium and bromide tracers were used to evaluate trapped gas during an infiltration pond experiment. Dissolved helium preferentially partitioned into trapped gas bubbles, or other pore air, because of its low solubility in water. This produced observed helium retardation factors of as much as 12 relative to bromide. Numerical...
