Evaluation of groundwater discharge into small lakes based on the temporal distribution of radon-222
N. T. Dimova, W. C. Burnett
2011, Limnology and Oceanography (56) 486-494
In order to evaluate groundwater discharge into small lakes we constructed a model that is based on the budget of 222Rn (radon, t1/2=3.8 d) as a tracer. The main assumptions in our model are that the lake's waters are well‐mixed horizontally and vertically; the only significant 222Rn source is via groundwater discharge;...
An Analysis of the Published Mineral Resource Estimates of the Haji-Gak Iron Deposit, Afghanistan
David M. Sutphin, Karine Renaud, Lawrence J. Drew
2011, Natural Resources Research (20) 329-353
The Haji-Gak iron deposit of eastern Bamyan Province, eastern Afghanistan, was studied extensively and resource calculations were made in the 1960s by Afghan and Russian geologists. Recalculation of the resource estimates verifies the original estimates for categories A (in-place resources known in detail), B (in-place resources known in moderate detail),...
Climate change, atmospheric rivers, and floods in California - a multimodel analysis of storm frequency and magnitude changes
Michael D. Dettinger
2011, Journal of the American Water Resources Association (47) 514-523
Recent studies have documented the important role that “atmospheric rivers” (ARs) of concentrated near‐surface water vapor above the Pacific Ocean play in the storms and floods in California, Oregon, and Washington. By delivering large masses of warm, moist air (sometimes directly from the Tropics), ARs establish conditions for the kinds...
Assessment and distribution of antimony in soils around three coal mines, Anhui, China
C. Qi, Gaisheng Liu, Y. Kang, P.K.S. Lam, C. Chou
2011, Journal of the Air and Waste Management Association (61) 850-857
Thirty-three soil samples were collected from the Luling, Liuer, and Zhangji coal mines in the Huaibei and Huainan areas of Anhui Province, China. The samples were analyzed for antimony (Sb) by inductively coupled plasma-optical emission spectrometry (ICP-OES) method. The average Sb content in the 33 samples was 4 mg kg−1,...
Maintenance of phenotypic variation: Repeatability, heritability and size-dependent processes in a wild brook trout population
B.H. Letcher, J.A. Coombs, K.H. Nislow
2011, Evolutionary Applications (4) 602-615
Phenotypic variation in body size can result from within-cohort variation in birth dates, among-individual growth variation and size-selective processes. We explore the relative effects of these processes on the maintenance of wide observed body size variation in stream-dwelling brook trout (Salvelinus fontinalis). Based on the analyses of multiple recaptures of...
Shallow conduit system at Kilauea Volcano, Hawaii, revealed by seismic signals associated with degassing bursts
Bernard Chouet, Phillip Dawson
2011, Journal of Geophysical Research B: Solid Earth (116) B12317
Eruptive activity at the summit of Kilauea Volcano, Hawaii, beginning in March, 2008 and continuing to the present time is characterized by episodic explosive bursts of gas and ash from a vent within Halemaumau Pit Crater. These bursts are accompanied by seismic signals that are well recorded by a broadband...
Fire and the origins of Mediterranean-type vegetation
Jon E. Keeley, William J. Bond, Ross A. Bradstock, Juli G. Pausas, Philip W. Rundel
2011, Book chapter, Fire in Mediterranean ecosystems: Ecology, evolution and management
The mediterranean-type climate (MTC) is widely agreed to have been in place in all five MTC regions since at least the late Pliocene (see Fig. 9.1), ~2 Ma, with much of the contemporary mediterranean-type vegetation (MTV) present and contributing to a highly fire-prone environment. There is far less agreement on:...
Rapid Holocene coastal change revealed by high-resolution micropaleontological analysis, Pamlico Sound, North Carolina, USA
Pre C. Grand, S.J. Culver, D. J. Mallinson, K.M. Farrell, D.R. Corbett, B. P. Horton, C. Hillier, S.R. Riggs, S.W. Snyder, M.A. Buzas
2011, Quaternary Research (76) 319-334
Foraminiferal analyses of 404 contiguous samples, supported by diatom, lithologic, geochronologic and seismic data, reveal both rapid and gradual Holocene paleoenvironmental changes in an 8.21-m vibracore taken from southern Pamlico Sound, North Carolina. Data record initial flooding of a latest Pleistocene river drainage and the formation of an estuary 9000....
Fire-adaptive trait evolution
Jon E. Keeley, William J. Bond, Ross A. Bradstock, Juli G. Pausas, Philip W. Rundel
2011, Book chapter, Fire in Mediterranean ecosystems: Ecology, evolution and management
Until relatively recently the importance of fire and the origin of fire-adaptive traits have received minimal attention from paleoecologists, and appreciation of this importance has varied across the different mediterranean-type climate (MTC) ecosystems. For example, Axelrod (1973) and Raven & Axelrod (1978) wrote extensive treatises on the origins of the...
Heterogeneous pumice populations in the 2.08-Ma Cerro Galán Ignimbrite: Implications for magma recharge and ascent preceding a large-volume silicic eruption
Heather M. Wright, Christopher B. Folkes, Ray A.F. Cas, Katharine V. Cashman
2011, Bulletin of Volcanology (73) 1513-1533
Triggering mechanisms of large silicic eruptions remain a critical unsolved problem. We address this question for the ~2.08-Ma caldera-forming eruption of Cerro Galán volcano, Argentina, which produced distinct pumice populations of two colors: grey (5%) and white (95%) that we believe may hold clues to the onset of eruptive activity....
Diverse, discrete, mantle-derived batches of basalt erupted along a short normal fault zone: The Poison Lake chain, southernmost Cascades
L.J.P. Muffler, M.A. Clynne, A.T. Calvert, D.E. Champion
2011, Geological Society of America Bulletin (123) 2177-2200
The Poison Lake chain consists of small, monogenetic, calc-alkaline basaltic volcanoes located east of the Cascade arc axis, 30 km ENE of Lassen Peak in northeastern California. This chain consists of 39 distinguishable units in a 14-km-long and 2-kmwide zone trending NNW, parallel to nearby Quaternary normal faults. The 39...
Stability of Mg-sulfates at-10C and the rates of dehydration/rehydration processes under conditions relevant to Mars
A. Wang, J.J. Freeman, I.-M. Chou, B.L. Jolliff
2011, Journal of Geophysical Research E: Planets (116)
We report the results of low temperature (−10°C) experiments on the stability fields and phase transition pathways of five hydrous Mg-sulfates. A low temperature form of MgSO4·7H2O (LT-7w) was found to have a wide stability field that extends to low relative humidity (∼13% RH at −10°C). Using information on the...
Egg size matching by an intraspecific brood parasite
Patrick R. Lemons, James S. Sedinger
2011, Behavioral Ecology (22) 696-700
Avian brood parasitism provides an ideal system with which to understand animal recognition and its affect on fitness. This phenomenon of laying eggs in the nests of other individuals has classically been framed from the perspective of interspecific brood parasitism and host recognition of parasitic eggs. Few examples exist of...
Fluorescent microspheres as surrogates in evaluating the efficacy of riverbank filtration for removing Cryptosporidium parvum oocysts and other pathogens
Ronald W. Harvey, David W. Metge, Rodney A. Sheets, Jay Jasperse
2011, Book chapter, Riverbank filtration for water security in desert countries. NATO Science for Peace and Security Series C: Environmental Security
A major benefit of riverbank filtration (RBF) is that it provides a relatively effective means for pathogen removal. There is a need to conduct more injection-and-recovery transport studies at operating RBF sites in order to properly assess the combined effects of the site heterogeneities and ambient physicochemical conditions, which are...
Fire and the fire regime framework
Jon E. Keeley, William J. Bond, Ross A. Bradstock, Juli G. Pausas, Philip W. Rundel
2011, Book chapter, Fire in Mediterranean ecosystems: Ecology, evolution and management
A global view of potential vs. actual vegetation distributions points to fire as a major driver of biome distribution and determinant of community structure (Bond et al. 2005). In ecological terms, fire acts much like an herbivore, consuming biomass and competing with biotic consumers for resources, and in this sense...
Mineralogical and geochemical evidence for hydrothermal activity at the west wall of 12°50′N core complex (Mid-Atlantic ridge): a new ultramafic-hosted seafloor hydrothermal deposit?
Vesselin Dekov, Tanya Boycheva, Ulf Halenius, Kjell Billstrom, George D. Kamenov, Wayne C. Shanks, Jens Stummeyer
2011, Marine Geology (288) 90-102
Dredging along the west wall of the core complex at 12°50′N Mid-Atlantic Ridge sampled a number of black oxyhydroxide crusts and breccias cemented by black and dark brown oxyhydroxide matrix. Black crusts found on top of basalt clasts (rubble) are mainly composed of Mn-oxides (birnessite, 10-Å manganates) with thin films...
Raman spectroscopic measurements of CO2 density: Experimental calibration with high-pressure optical cell (HPOC) and fused silica capillary capsule (FSCC) with application to fluid inclusion observations
X. Wang, I-Ming Chou, W. Hu, Robert Burruss, Q. Sun, Y. Song
2011, Geochimica et Cosmochimica Acta (75) 4080-4093
Raman spectroscopy is a powerful method for the determination of CO2 densities in fluid inclusions, especially for those with small size and/or low fluid density. The relationship between CO2 Fermi diad split (Δ, cm−1) and CO2 density (ρ, g/cm3) has been documented by several previous studies. However, significant discrepancies exist among these...
Revisiting the Earth's sea-level and energy budgets from 1961 to 2008
John A. Church, Neil J. White, Leonard F. Konikow, Catia M. Domingues, J. Graham Cogley, Eric Rignot, Jonathan M. Gregory, Michiel R. van den Broeke, Andrew J. Monaghan, Isabella Velicogna
2011, Geophysical Research Letters (38)
We review the sea-level and energy budgets together from 1961, using recent and updated estimates of all terms. From 1972 to 2008, the observed sea-level rise (1.8 0.2 mm yr-1 from tide gauges alone and 2.1 0.2 mm yr -1 from a combination of tide gauges and altimeter observations) agrees...
Excess nitrogen in the U.S. environment: Trends, risks, and solutions
E.A. Davidson, M.B. David, J.N. Galloway, C.L. Goodale, R. Haeuber, J. A. Harrison, R. W. Howarth, D.B. Jaynes, R.R. Lowrance, Nolan B. Thomas, J.L. Peel, R.W. Pinder, E. Porter, C.S. Snyder, A.R. Townsend, M.H. Ward
2011, Issues in Ecology
It is not surprising that humans have profoundly altered the global nitrogen (N) cycle in an effort to feed 7 billion people, because nitrogen is an essential plant and animal nutrient. Food and energy production from agriculture, combined with industrial and energy sources, have more than doubled the amount of...
Critical nitrogen deposition loads in high-elevation lakes of the western US inferred from paleolimnological records
J.E. Saros, David W. Clow, T. Blett, A.P. Wolfe
2011, Water, Air, & Soil Pollution (216) 193-202
Critical loads of nitrogen (N) from atmospheric deposition were determined for alpine lake ecosystems in the western US using fossil diatom assemblages in lake sediment cores. Changes in diatom species over the last century were indicative of N enrichment in two areas, the eastern Sierra Nevada, starting between 1960 and...
USGS science in the gulf oil spill: Novel science applications in a crisis
M. McNutt
2011, Sea Technology (52) 13-14
Marcia McNutt reflects on the role of the US Geological Survey (USGS) team following the Deepwater Horizon oil spill. Secretary Salazar asked Marcia McNutt to lead the Flow Rate Technical Group, a team charged by National Incident Commander Adm. Thad Allen with improving estimates of the oil discharge rate from...
Agave turneri (Agavaceae), a new species from northeastern Baja California, Mexico
R. H. Webb, J. M. Salazar-Cesena
2011, Brittonia (63) 203-210
Agave turneri, a new species of Agave from the Sierras Cucap?? and El Mayor in northeastern Baja California, Mexico, is a medium-sized species that does not produce offsets, has a relatively short and narrow panicle, and has a distinctive flower structure. The closest relatives to this new species are Agave...
Using spatiotemporal models and distance sampling to map the space use and abundance of newly metamorphosed Western Toads (Anaxyrus boreas)
Nathan D. Chelgren, Barbara Samora, M. J. Adams, Brome McCreary
2011, Herpetological Conservation and Biology (6) 175-190
High variability in abundance, cryptic coloration, and small body size of newly metamorphosed anurans have limited demographic studies of this life-history stage. We used line-transect distance sampling and Bayesian methods to estimate the abundance and spatial distribution of newly metamorphosed Western Toads (Anaxyrus boreas) in terrestrial habitat surrounding a montane...
The ShakeOut Scenario: Meeting the needs for construction aggregates, hot mix asphalt, and ready mix concrete
William H. Langer
2011, Earthquake Spectra (27) 505-520
An Mw 7.8 earthquake as described in the ShakeOut Scenario would cause significant damage to buildings and infrastructure. Over 6 million tons of newly mined aggregate would be used for emergency repairs and for reconstruction in the five years following the event. This aggregate would be applied mostly in the form...
U.S. Geological Survey: A synopsis of Three-dimensional Modeling
Linda J. Jacobsen, Pierre D. Glynn, Geoff A. Phelps, Randall C. Orndorff, Gerald W. Bawden, V. J. S. Grauch
2011, Book chapter, Chapter 13 in <i>Synopsis of Current Three-dimensional Geological Mapping and Modeling in Geological Survey Organizations</i>
The U.S. Geological Survey (USGS) is a multidisciplinary agency that provides assessments of natural resources (geological, hydrological, biological), the disturbances that affect those resources, and the disturbances that affect the built environment, natural landscapes, and human society. Until now, USGS map products have been generated and distributed primarily as 2-D...
