Hydrologic-energy balance constraints on the Holocene lake-level history of lake Titicaca, South America   总被引：1，自引：0，他引：1  

H. D. Rowe  R. B. Dunbar 《Climate Dynamics》2004,23(3-4):439-454

A basin-scale hydrologic-energy balance model that integrates modern climatological, hydrological, and hypsographic observations was developed for the modern Lake Titicaca watershed (northern Altiplano, South America) and operated under variable conditions to understand controls on post-glacial changes in lake level. The model simulates changes in five environmental variables (air temperature, cloud fraction, precipitation, relative humidity, and land surface albedo). Relatively small changes in three meteorological variables (mean annual precipitation, temperature, and/or cloud fraction) explain the large mid-Holocene lake-level decrease (85 m) inferred from seismic reflection profiling and supported by sediment-based paleoproxies from lake sediments. Climatic controls that shape the present-day Altiplano and the sediment-based record of Holocene lake-level change are combined to interpret model-derived lake-level simulations in terms of changes in the mean state of ENSO and its impact on moisture transport to the Altiplano.  相似文献   

The 1994 Sefidabeh (eastern Iran) earthquakes revisited: new evidence from satellite radar interferometry and carbonate dating about the growth of an active fold above a blind thrust fault   总被引：2，自引：0，他引：2  

B. Parsons  T. Wright  P. Rowe  J. Andrews  J. Jackson  R. Walker  M. Khatib  M. Talebian  E. Bergman  E. R. Engdahl 《Geophysical Journal International》2006,164(1):202-217

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NEAR飞船对C型小行星（253 Mathilde）的探测     

Bell.  JF 《紫金山天文台台刊》1998,17(2):42-48

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A comparison of microwave radiometric data and modeled snowpack conditions for Dye 2, Greenland     

T. L. Mote  C. M. Rowe 《Meteorology and Atmospheric Physics》1996,59(3-4):245-255

Summary Meteorological observations were recorded at Dye 2, Greenland during the summer of 1993 as part of a research program to identify interannual variations in melt occurrence on the Greenland ice sheet from satellite microwave data. The meteorological observations were used to drive and energy-balance model of the snowpack during 21 June to 13 July 1993. Time series of the meteorological observations and various model outputs were compared to a concurrent time series of Special Sensor Microwave/Imager (SSM/I) data for scan cells centered within 25 km of Dye 2. The satellite microwave observations clearly show an increase in snowpack emissivity at the same time that the model indicates liquid water forming in the snow. Diurnal melt-freeze cycles that occurred during mid June to early July resulted in an increase in the 37 GHz brightness temperature as great as 60K from the dry, refrozen snow in the morning to the wet snow of some afternoons. The effects of fresh snowfall, which tend to increase the brightness temperature, and of snow growth from melt-freeze metamorphism, which tend to decrease the brightness temperature, are also apparent in the microwave observations. The results of this work demonstrate the influence of daily weather variations on the microwave emissivity in the ice sheet's percolation zone and the usefulness of swath data to diagnose the diurnal cycle of melt.With 4 Figures  相似文献   

Using Automated, High-precision Repicking to Improve Delineation of Microseismic Structures at the Soultz Geothermal Reservoir     

C. A. Rowe  R.C. Aster  W.S. Phillips  R.H. Jones  B. Borchers  M.C. Fehler 《Pure and Applied Geophysics》2002,159(1-3):563-596

—?An automatic, adaptive, correlation-based algorithm for adjusting phase picks in large digital seismic data sets provides significant improvement in resolution of microseismic structures using only a small fraction of the time and manpower which would be required to re-analyze waveforms manually or semi-automatically. We apply this technique to induced seismicity at the Soultz-sous-Forêts geothermal site, France. The method is first applied to a small, previously manually repicked subset of the catalogue so that we may compare our results to those obtained from painstaking, visual, cross-correlation-based techniques. Relative centroid-adjusted hypocenters show a decrease in median mislocation from 31 to 7?m for preliminary and automatically adjusted picks, respectively, compared to the manual results. Narrow, intersecting joint features not observed in the preliminary hypocenter cloud, but revealed through manual repicking, are also recovered using the automatic method. We then address a larger catalogue of ～7000 microearthquakes. After relocating the events using automatic repicks, the percentage of events clustering within 5?m of their nearest neighbor increases form 5 to 26% of the catalogue. Hypocenter relocations delineate narrow, linear features previously obscured within the seismic cloud, interpreted as faults or fractures which may correspond to fluid propagation paths, or to changes in stress as a result of elevated pore pressures. RMS travel-time residuals for the larger data set are reduced by only 0.2%; however, phase-pick biases in the preliminary catalogue have influenced both the velocity model and station correction calculations, which will affect location residuals. These pick biases are apparent on the adjusted, stacked waveforms and correcting them will be important prior to future velocity model refinements.  相似文献   

U-series dating of Hoxnian interglacial deposits at Marks Tey,Essex, England     

P. J. Rowe  T. C. Atkinson  C. Turner 《第四纪科学杂志》1999,14(7):693-702

A U–Th dating study was carried out on the authigenic carbonate component of interglacial lake sediments at Marks Tey, Essex, England. Isochron methods were necessary because of the presence of non-carbonate detritus. Calculated dates around the limit of the U–Th method were obtained for two horizons. Error limits were determined by Monte Carlo sampling from the normal distributions of errors in the isotope ratios. Comparison of the resulting empirical distribution functions with the marine oxygen isotope time-scale indicates with 87% confidence that the Marks Tey sediments correlate with OIS 11 or some older stage. As the Marks Tey deposits rest without stratigraphical break on Anglian till, and can be firmly correlated with the Hoxnian interglacial type site at Hoxne, Suffolk, England, this result implies that the Anglian glaciation took place in OIS 12 and the Hoxnian Stage of the British chronostratigraphy commenced in OIS 11. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   

Monitoring an Experimental Soil Waste Near London, Ontario, Canada     

E.K. Yanful  P.H. Simms  R.K. Rowe  G. Stratford 《Geotechnical and Geological Engineering》1999,17(2):65-84

An experimental soil cover was constructed near London, Ontario and monitored for more than a year for percolation and water content data. The cover was a multi-layer system consisting of compacted till barrier soil placed between gravel layers, and a final topsoil cap in one half and a coarse stone cap in the other half. The lower gravel layer was intended to provide a capillary break that would minimize gravity driven drainage in the till, while the capillary barrier created at the upper gravel-till interface would reduce evaporative losses in the till during dry periods. The results showed that while the compacted till maintained a relatively high degree of saturation and low hydraulic conductivity under the coarse stone, it desiccated under the topsoil and resulted in high water percolation rates. The textural or grain size contrast between the relatively fine topsoil and the underlying gravel layer created a capillary break which, together with the relatively low hydraulic conductivity of the topsoil, prevented infiltrating waters from recharging the underlying till. Thus the till was not able to rebound to its pre-desiccation water content. The saturated hydraulic conductivity of the till under the topsoil was about 1 × 10^-8 m/s after one year, compared to 2.0 × 10^-10 m/s at construction.  相似文献   

Obituary—John R. Booker     

John Carter  Chandra S. Desai  R. Kerry Rowe  Ian M. Smith  W. Wittke 《国际地质力学数值与分析法杂志》1998,22(6):421-423

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Chronic exposure of Leptocheirus plumulosus to Baltimore Harbor sediment: bioenergetic and population-level effects   总被引：1，自引：0，他引：1  

Manyin T  Rowe CL 《Marine environmental research》2006,62(2):116-130

We investigated the long-term effects of contaminants in sediment from Baltimore Harbor, MD, USA, on a burrowing amphipod (Leptocheirus plumulosus) via a full life-cycle laboratory exposure. Contaminants in the Baltimore Harbor sediment included PAHs (10,800 ng/g), PCBs (152 ng/g), and heavy metals (including As, Cd, Cu, Pb, Hg, Ni, and Zn). Exposures were initiated with neonate amphipods, placed in microcosms containing either contaminated or reference sediment, and were maintained for 42 days, allowing ample time for the initial cohort to mature and reproduce. At the end of the exposure period, the populations of amphipods were surveyed to ascertain the number and size of amphipods in each size class (neonate, juvenile, and adult), and bioenergetic measurements were performed on adults, including metabolic rate, lipid content, and fecundity. Contaminated sediment from Baltimore Harbor caused lower growth and reproductive rates; in Baltimore Harbor sediment, the average dry weight of amphipod offspring in each size class was significantly lower and there were less than one-third as many individuals in each size class, compared to reference sediment. By the end of the exposure, the total amphipod biomass in Baltimore Harbor sediment was less than one quarter of that in reference sediment. On average, gravid females in reference sediment produced at least twice as many viable offspring as those in contaminated sediment. Adult male amphipods in Baltimore Harbor sediment possessed significantly lower lipid concentrations. Lipid content in neonates also appeared to be negatively affected by parental exposure to contaminants. Metabolic rate was elevated in adult amphipods exposed to Baltimore Harbor sediment. Overall, the results suggest that contaminated sediment conditions in the urban estuary may chronically affect L. plumulosus by diverting energy from production to maintenance pathways, resulting in slower growth and reduced fecundity, and ultimately leading to retarded population growth rates. The results of this study reinforce the need for long-term toxicological exposures to reveal chronic effects.  相似文献   

The analysis of pollutant migration through soil with linear hereditary time-dependent sorption     

David W. Smith  R. Kerry Rowe  John R. Booker 《国际地质力学数值与分析法杂志》1993,17(4):255-274

This paper presents a non-equilibrium sorption dispersion–advection transport model for the analysis of pollutant migration through soil. The formulation involves a convolution integral of the product of the rate of change of concentration and a time-dependent sorption coefficient, suggesting an integral transformation of the governing equations. This facilitates the primary purpose of this paper, to incorporate a time-dependent solute sorption process into a computationally efficient and accurate semi-analytic Laplace transform method. An application of the non-equilibrium sorption model for backfiguring dispersion–advection equation parameters from experimental data is presented, and the implications of non-equilibrium sorption on the design of landfill liners is explored by means of an illustrative example.  相似文献