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Genesis And Morphology Of Soil Pendants In Quaternary Landforms Of Pahranagat Valley, Nevada, Amy Lynn Brock Aug 2002

Genesis And Morphology Of Soil Pendants In Quaternary Landforms Of Pahranagat Valley, Nevada, Amy Lynn Brock

UNLV Theses, Dissertations, Professional Papers, and Capstones

Five geomorphic surfaces present in the northern Pahranagat Valley, Lincoln County, Nevada range in age from Early Pleistocene to Recent (Q1-Q5) and vary in clast lithology from dolomite to volcanic tephras. Two chronosequences and 5 lithosequences were compared to evaluate micro and macromorphic characteristics and development of soil pendants. This study presents a new interpretation for soil pendant development. Key features observed in the Pahranagat Valley pendants provide evidence for precipitation at the clast-pendant contact suggesting that newer deposits are not always found at the pendant terminus as other studies have assumed. These features include a void at the clast-pendant …


Groundwater Study Of The Wandering Townsite, S Ghauri Aug 2002

Groundwater Study Of The Wandering Townsite, S Ghauri

Resource management technical reports

A groundwater study was carried out in the townsite of Wandering, Western Australia. This report describes the town and its catchment, the hydrogeological investigation characterising groundwater flow systems within the townsite, and recommends actions for managing salinity risk.


The Bull Run River–Reservoir System Model, Robert Leslie Annear, Scott A. Wells Aug 2002

The Bull Run River–Reservoir System Model, Robert Leslie Annear, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

The Bull Run watershed is located 41.8 kilometers east of Portland, Oregon in the Mt. Hood National Forest and consists of two reservoirs supplying drinking water to over 840,000 people in the Portland metropolitan area. In March 1998 Steelhead and Spring Chinook were listed as threatened in the Lower Columbia basin under the Endangered Species Act. Historical reservoir operations during the summer released no water downstream resulting in stream temperatures exceeding the state water quality standard for salmonids. CE-QUAL-W2 Version 3 is a two-dimensional water quality and hydrodynamic model capable of modeling watersheds with interconnected rivers, reservoirs and estuaries. CE-QUAL-W2 …


Basis Of The Ce-Qual-W2 Version 3 River Basin Hydrodynamic And Water Quality Model, Scott A. Wells Aug 2002

Basis Of The Ce-Qual-W2 Version 3 River Basin Hydrodynamic And Water Quality Model, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

CE-QUAL-W2 Version 3, a 2-D (longitudinal-vertical) hydrodynamic and water quality model for river basins combining both river and stratified river-estuary and lake-reservoir flow, is a development product of the Waterways Experiment Station in Vicksburg, MS, USA. With the development and release of any revised or reformulated model codes, significant model validation is required. This includes comparison of model results to simple analytical solutions for hydrodynamics and water quality transport, as well as comparison to laboratory and field data. In this paper, the model is compared to numerous analytical solutions for mass transport (1- D advective mass transport) and hydrodynamics (impulsive …


Field Trip Guide (For The Nebraska Well Drillers Association) Southwestern Nebraska Geology, Duane Eversoll, Jim Goeke Jul 2002

Field Trip Guide (For The Nebraska Well Drillers Association) Southwestern Nebraska Geology, Duane Eversoll, Jim Goeke

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Support For Infiltration And Seepage Studies In Exploratory Studies Facility Niches And Alcoves, Irene Farnham, Klaus J. Stetzenbach, Amy J. Smiecinski Jul 2002

Support For Infiltration And Seepage Studies In Exploratory Studies Facility Niches And Alcoves, Irene Farnham, Klaus J. Stetzenbach, Amy J. Smiecinski

Publications (YM)

This report details the analyses performed under Task 9 of the University and Community College System of Nevada (UCCSN) Cooperative Agreement with the US Department of Energy (DOE). This task, titled "Analysis of Chemical Tracers in Conjunction with the Vadose Zone Infiltration and Seepage Studies", provided for the development of analytical procedures and the analysis of samples from a tracer test currently in progress at Alcove 8 /Niche 3 in the Exploratory Studies Facility (ESF). The concentration of two tracers (bromide andpentafluorobenzoic acid) were quantified in the initial injectate solution and also the seepage samples collected from Niche 3. Samples …


The Mount Feather Diamicton Of The Sirius Group: An Accumulation Of Indicators Of Neogene Antarctic Glacial And Climatic History, G. A. Wilson, J. A. Barron, A. C. Ashworth, R. A. Askin, J. A. Carter, M. G. Curren, D. H. Dalhuisen, E. I. Friedmann, D. G. Fyodorov-Davidov, D. A. Gilichinsky, M. A. Harper, David M. Harwood, J. F. Hiemstra, T. R. Janecek, K. J. Licht, V. E. Ostroumov, R. D. Powell, E. M. Rivkina, S. A. Rose, A. P. Stroeven, P. Stroeven, J. J. M. Van Der Meer, M. C. Wizevich Jul 2002

The Mount Feather Diamicton Of The Sirius Group: An Accumulation Of Indicators Of Neogene Antarctic Glacial And Climatic History, G. A. Wilson, J. A. Barron, A. C. Ashworth, R. A. Askin, J. A. Carter, M. G. Curren, D. H. Dalhuisen, E. I. Friedmann, D. G. Fyodorov-Davidov, D. A. Gilichinsky, M. A. Harper, David M. Harwood, J. F. Hiemstra, T. R. Janecek, K. J. Licht, V. E. Ostroumov, R. D. Powell, E. M. Rivkina, S. A. Rose, A. P. Stroeven, P. Stroeven, J. J. M. Van Der Meer, M. C. Wizevich

Department of Earth and Atmospheric Sciences: Faculty Publications

A paucity of data from the Antarctic continent has resulted in conflicting interpretations of Neogene Antarctic glacial history. Much of the debate centres on interpretations of the glacigene Sirius Group strata that crop out as discrete deposits along the length of the Transantarctic Mountains and in particular on its age and the origin of the siliceous microfossils it encloses. Pliocene marine diatoms enclosed within Sirius Group strata are inferred to indicate a dynamic East Antarctic ice sheet that was much reduced, compared with today, in the early-middle Pliocene and then expanded again in the late Pliocene. However, the geomorphology of …


Geomorphic Effectiveness, Sandur Development, And The Pattern Of Landscape Response During Jökulhlaups: Skeiöarársandur, Southeastern Iceland, F. J. Magilligan, B. Gomez, L. A. K. Mertes, L. C. Smith, Norman D. Smith, D. Finnegan, J. B. Garvin Jul 2002

Geomorphic Effectiveness, Sandur Development, And The Pattern Of Landscape Response During Jökulhlaups: Skeiöarársandur, Southeastern Iceland, F. J. Magilligan, B. Gomez, L. A. K. Mertes, L. C. Smith, Norman D. Smith, D. Finnegan, J. B. Garvin

Department of Earth and Atmospheric Sciences: Faculty Publications

By contrast with other historical outburst floods on Skeióarársandur, the 1996 jökulhlaup was unprecedented in its magnitude and duration, attaining a peak discharge of ~53,000 m3/s in <17 h. Using a combination of field sampling and remote sensing techniques (Landsat TM, SAR interferometry, airphotos, and laser altimetry), we document the sandur-wide geomorphic impacts of this event. These impacts varied widely across the Skeióarársandur and cannot be singularly attributed to jökulhlaup magnitude because pre-jökulhlaup glacial dynamics and the extant setting largely conditioned the spatial pattern, type, and magnitude of these impacts. Topographic lowering and asymmetric retreat of the ice front during the late twentieth century has decoupled the ice sheet from the moraine/sandur complex along the central and western sandur. This glacial control, in combination with the convex topography of the proximal sandur, promoted a shift from a primarily diffuse-source braided outwash system to a more point-sourced, channelized discharge of water and sediment. Deposition dominated within the proglacial depression, with approximately 3.8*107 m3 of sediment, and along channel systems that remained connected to subglacial sediment supplies. This shift to a laterally dissimilar, channelized routing system creates a more varied depositional pattern that is not explicitly controlled by the concave longitudinal profile down-sandur. Laterally contiguous units, therefore, may vary greatly in age and sediment character, suggesting that current facies models inadequately characterize sediment transfers when the ice front is decoupled from its …


Beginning A New Era Of Drought Monitoring Across North America, Jay Lawrimore, Richard R. Heim Jr., Mark D. Svoboda, Val Swail, Phil J. Englehart Jul 2002

Beginning A New Era Of Drought Monitoring Across North America, Jay Lawrimore, Richard R. Heim Jr., Mark D. Svoboda, Val Swail, Phil J. Englehart

National Drought Mitigation Center: Faculty Publications

Drought experts from the United States, Canada, and Mexico met at the National Climatic Data Center in Asheville, North Carolina, for a three-day workshop in late April 2002 to discuss the United States Drought Monitor program and to develop a plan for initiating a new program of drought monitoring for North America. Since its inception in 1999, the U.S. Drought Monitor (DM) has been extremely successful in assessing and communicating the state of drought in the United States on a weekly basis. This success, and the recognition that an ongoing comprehensive and integrated drought assessment was needed throughout all three …


Groundwater Study Of The Trayning Townsite, Louise Hopgood Jul 2002

Groundwater Study Of The Trayning Townsite, Louise Hopgood

Resource management technical reports

A groundwater study was carried out in the townsite of Trayning, Western Australia. The study presents a model of the hydrogeology below the town and defines management options to help limit damage to infrastructure from surface water, shallow subsurface water and deep groundwater. A drilling program and expansion of the network of monitoring bores were also part of the study.


Structural And Geomorphological Evolution Of Huangshan (Yellow Mountain), Anhui Province, China, Pei-Hua Huang, Robert F. Diffendal Jr., Ming-Qing Yang Jul 2002

Structural And Geomorphological Evolution Of Huangshan (Yellow Mountain), Anhui Province, China, Pei-Hua Huang, Robert F. Diffendal Jr., Ming-Qing Yang

School of Natural Resources: Faculty Publications

Huangshan (Yellow Mountain) is an 1864-m granite massif situated at 30° 10′ N and 118° 11′ E, south of the lower reaches of the Yangtze River. The granite formed during the Early Cretaceous and was subsequently uplifted several times along faults. After the initial uplift, about 54 Ma, erosion proceeded to wear away the mountain for the next 30 Ma. By 24 Ma the Bright Summit Peneplain had formed. Renewed uplift in the Miocene along the same fault systems produced a mountain in the same place as the original one. This mountain was eroded to produce a second mature denudational …


Cranbrook-Toolbrunup : Catchment Appraisal Report 2001, Tim D. Overheu, Western South Coast Catchment Appraisal Team (Wa) Jul 2002

Cranbrook-Toolbrunup : Catchment Appraisal Report 2001, Tim D. Overheu, Western South Coast Catchment Appraisal Team (Wa)

Resource management technical reports

This report covers the eastern junction of both the Pallinup North Stirling and Kent Frankland sub-regions, comprising of six amalgamated sub-catchments of Pingelup Creek, Solomons Creek, Racecourse Lake, Lake Toolbrunup, Twolganup Brook and Hamilla Hill (west). This report primarily focuses on the agricultural and natural resources at risk within the study area and attempts to identify options to manage the potential risks.


Public Attitudes And Knowledge Of The Black-Tailed Prairie Dog: A Common And Controversial Species, Donna Lybecker, Berton Lee Lamb, Phadrea Ponds Jul 2002

Public Attitudes And Knowledge Of The Black-Tailed Prairie Dog: A Common And Controversial Species, Donna Lybecker, Berton Lee Lamb, Phadrea Ponds

United States Geological Survey: Staff Publications

Black-tailed prairie dogs (Cynomys ludovicianus; hereafter, prairie dogs) are native to the short-grass prairie region of North America from Mexico to Canada (figure 1).According to government documents (64 Federal Register 57 at 14426–14427), before the 19th century expansion of the United States, prairie dogs inhabited millions of acres of the Great Plains and lived in huge colonies west of the Missouri River. Settlement of the Great Plains and the transformation of vast areas from native grassland to tilled farmland forever changed the prairie ecosystem and prairie dog habitat.
Over the course of the last century, the habitat range …


Groundwater Flow To A Horizontal Or Slanted Well In An Unconfined Aquifer, Hongbin Zhan, Vitaly A. Zlotnik Jul 2002

Groundwater Flow To A Horizontal Or Slanted Well In An Unconfined Aquifer, Hongbin Zhan, Vitaly A. Zlotnik

Department of Earth and Atmospheric Sciences: Faculty Publications

New semianalytical solutions for evaluation of the drawdown near horizontal and slanted wells with finite length screens in unconfined aquifers are presented. These fully three-dimensional solutions consider instantaneous drainage or delayed yield and aquifer anisotropy. As a basis, solution for the drawdown created by a point source in a uniform anisotropic unconfined aquifer is derived in Laplace domain. Using superposition, the point source solution is extended to the cases of the horizontal and slanted wells. The previous solutions for vertical wells can be described as a special case of the new solutions. Numerical Laplace inversion allows effective evaluation of the …


Willamette River And Columbia River Waste Load Allocation Model, Chris Berger, Robert Leslie Annear, Scott A. Wells Jul 2002

Willamette River And Columbia River Waste Load Allocation Model, Chris Berger, Robert Leslie Annear, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

A hydrodynamic and water quality model of the Lower Willamette River was developed to evaluate management alternatives designed to improve water quality. The Lower Willamette River is located in Oregon and drains a watershed covering 11500 square miles consisting of forested, agricultural, and urban lands. Inflows include treated municipal wastes and industrial effluents along with non-point sources from agricultural, silvicultural and urbanized land. The model was designed to address temperature, dissolved oxygen, algae, pH and bacteria concerns. The Corps of Engineers two-dimensional, laterally averaged, hydrodynamic and water quality model CE-QUAL-W2, Version 3 was applied. CE-QUAL-W2 consists of directly coupled hydrodynamic …


Microbial Composition Of Near-Boiling Silica-Depositing Thermal Springs Throughout Yellowstone National Park, Carrine E. Blank, Sherry L. Cady, Norman R. Pace Jul 2002

Microbial Composition Of Near-Boiling Silica-Depositing Thermal Springs Throughout Yellowstone National Park, Carrine E. Blank, Sherry L. Cady, Norman R. Pace

Geology Faculty Publications and Presentations

The extent of hyperthermophilic microbial diversity associated with siliceous sinter (geyserite) was characterized in seven near-boiling silica-depositing springs throughout Yellowstone National Park using environmental PCR amplification of small-subunit rRNA genes (SSU rDNA), large-subunit rDNA, and the internal transcribed spacer (ITS). We found that Thermocrinis ruber, a member of the order Aquificales, is ubiquitous, an indication that primary production in these springs is driven by hydrogen oxidation. Several other lineages with no known close relatives were identified that branch among the hyperthermophilic bacteria. Although they all branch deep in the bacterial tree, the precise phylogenetic placement of many of these lineages …


Biogeochemistry Of The Middle Rio Grande Bosque: Links Among Surface Water, Groundwater, And Sediments, Susan E. Block Jun 2002

Biogeochemistry Of The Middle Rio Grande Bosque: Links Among Surface Water, Groundwater, And Sediments, Susan E. Block

Earth and Planetary Sciences ETDs

The potential for water contamination is great in areas where land use is both urban and agricultural. Such land uses can load the surface water and groundwater with nutrients and toxic trace metals. Water pollution can be further increased when natural watersheds have been altered by human activities. The surface and groundwaters of the Middle Rio Grande, NM, USA are part of one such ecosystem.

Because redox processes are important controls on nutrient cycling and contaminant transport, it is vital to understand the redox zonation of an aquifer. This research has been conducted to address such biogeochemical zonation in the …


Volcanic Eruptions On Mid-Ocean Ridges: New Evidence From The Superfast Spreading East Pacific Rise, 17˚-19˚S, John Sinton, Eric Bergmanis, Ken Rubin, Rodey Batiza, Tracy K P Gregg, Karl Gronvold, Ken C. Macdonald, Scott M. White Jun 2002

Volcanic Eruptions On Mid-Ocean Ridges: New Evidence From The Superfast Spreading East Pacific Rise, 17˚-19˚S, John Sinton, Eric Bergmanis, Ken Rubin, Rodey Batiza, Tracy K P Gregg, Karl Gronvold, Ken C. Macdonald, Scott M. White

Faculty Publications

Side-scan sonar, submersible observations and sampling of lava flows from the East Pacific Rise, 17_–19_S constrain the character and variability of submarine volcanic eruptions along mid-ocean ridges. Nine separate lava sequences were mapped using relative age and lithological contrasts among recovered samples. Axial lengths activated during eruptive episodes range from _1 to >18 km; individual flow field areas vary from <1 to >19 km2. Estimated erupted volumes range from <1 to >200 _ 106 m3. The largest unit is the chemically uniform Animal Farm lava near 18_370S. The youngest lava is the Aldo-Kihi flow field, 17_240–340S, probably erupted in the early 1990s from a …


Distribution Of Channel Catfish Life Stages In A Prairie River Basin, Jason C. Vokoun, Charles F. Rabeni Jun 2002

Distribution Of Channel Catfish Life Stages In A Prairie River Basin, Jason C. Vokoun, Charles F. Rabeni

United States Geological Survey: Staff Publications

To describe the pattern of use by age 0, juvenile, and adult channel catfish (Ictalurus punctatus) in a prairie river basin, we collected concurrent samples from tributaries and mainstem study sites in the Grand River basin of northern Missouri. Using standardized methods, we made collections in June, August, and October of 1997 and 1998. Age 0 channel catfish were found in all three streams in August, but rarely were observed in the tributaries during October. Juveniles (ages 1-3) and adults were observed in all three streams in all three months sampled. Tag returns suggested that age 2 and …


Soil Groups Of Western Australia: A Simple Guide To The Main Soils Of Western Australia (3rd Edn), Noel Schoknecht Jun 2002

Soil Groups Of Western Australia: A Simple Guide To The Main Soils Of Western Australia (3rd Edn), Noel Schoknecht

Resource management technical reports

No abstract provided.


Hill Air Force Base: Archaeological Monitoring Of Target And Access Road Development For The Ts-5-2 Target Area, Utah Test And Training Range, Tooele County, Utah, Daron Duke Jun 2002

Hill Air Force Base: Archaeological Monitoring Of Target And Access Road Development For The Ts-5-2 Target Area, Utah Test And Training Range, Tooele County, Utah, Daron Duke

All U.S. Government Documents (Utah Regional Depository)

The U.S. Army Corps of Engineers, Fort Worth District, contracted with Geo-Marine, Inc., to conduct archaeologial monitoring for a U.S. Air Force Air Combat Command (ACC) project on the Utah Test and Training Range (UTTR), which is under the jurisdiction of Hill Air Force Base and located in Tooele County, western Utah. Monitoring of ground disturbing activities associated with ACC development of Target TS-5-2 and a 2.5-mile dirt access road on the TS-5 (Wild Isle) area of UTTR was undertaken in January 2001. Additional target and access road development monitoring was conducted in July and August of 2001, and the …


Selection Of Nesting Habitat By Sharptailed Grouse In The Nebraska Sandhills, Bart L. Prose, Brian S. Cade, Dale Hein Jun 2002

Selection Of Nesting Habitat By Sharptailed Grouse In The Nebraska Sandhills, Bart L. Prose, Brian S. Cade, Dale Hein

United States Geological Survey: Staff Publications

We evaluated nesting habitat selection (disproportionate use compared to availability) by plains sharp-tailed grouse (Tympanuchus phasianellus jamesi) on rangelands grazed by cattle (Bas taurus) relative to height, density, and heterogeneity of residual herbaceous vegetation remaining from previous growing seasons. Residual cover is critical for nesting sharp-tailed grouse and can be lacking on grazed rangelands. Aerial photography and a geographic information system were used to analyze residual cover height classes and several measures of residual cover heterogeneity in nest (n = 38) and random (n = 38) plots. Height classes corresponded to visual obstruction readings (YORs), the …


Developing An Environmental Management System (Ems) For Viticulture, Catherine Nind Jun 2002

Developing An Environmental Management System (Ems) For Viticulture, Catherine Nind

Agriculture reports

This guidebook outlines one approach that may be used to develop an Environmental Management System (EMS) for a vineyard. The system described in this guidebook facilitates a continual improvement in environmental management and can be used to demonstrate a commitment to responsible land management. The system is generally consistent with the requirements of ISO 14001: the internationally accepted standard for an EMS.


Organic Geochemical Analysis Of Late-Glacial And Early-Holocene Ecosystem Changes: A Case Study From Northern New England Lakes, Michael A. Kruge, Andrea Lini Jun 2002

Organic Geochemical Analysis Of Late-Glacial And Early-Holocene Ecosystem Changes: A Case Study From Northern New England Lakes, Michael A. Kruge, Andrea Lini

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The lacustrine sedimentary archive of organic remains provides important evidence for the reconstruction of the environmental histories of lakes and their watersheds, recording the response of the Earth's biota to changes on scales varying from the local to the global. The last Glacial-Interglacial transition presents an opportunity to investigate how, and at what rates, watershed and lake ecosystems were established on once glaciated, carbon and nutrient-poor landscapes. The small lakes of northern Vermont (USA) provide an appropriate setting in which to investigate such changes.

As part of a multidisciplinary study of three Vermont lake sediment cores, samples ranging in age …


Deformational Features In The Chattanooga Shale, Near Chattanooga, Tennessee, Dewayne Adarial Ponds Jun 2002

Deformational Features In The Chattanooga Shale, Near Chattanooga, Tennessee, Dewayne Adarial Ponds

Honors Theses

Several exposures of deformed middle Paleozoic rocks in the westernmost Valley and Ridge Physiographic Province, near Chattanooga, TN, reveal a variety of structures. These include centimeter-scale ellipsoidal to lensshaped masses of sandstone in the Mississippian to Devonian Chattanooga Shale. Fissility in the carbonaceous shale is intensified adjacent to these lenses and conforms to their biconvex shapes. Slickensides on rinds of highly polished shale trend northwest. The walnut- to fist-size masses are composed of fine- to medium-grained ferruginous quartz sandstone. Thin-section study reveals that the quartz grains retain detrital characteristics, but that many are broken and displaced; cataclastic deformation is particularly …


The Role Of Groundwater And Surface Water Interaction In The Development Of A 1,4-Dioxane Plume In Scio Township, Washtenaw County, Michigan, James W. Brode Jun 2002

The Role Of Groundwater And Surface Water Interaction In The Development Of A 1,4-Dioxane Plume In Scio Township, Washtenaw County, Michigan, James W. Brode

Masters Theses

The purpose of this study was to examine the hypothesis that groundwater and surface water interaction resulted in the development a 1,4-dioxane plume in a glacial aquifer in Scio Township, Washtenaw County, Michigan.

An industrial solvent, 1,4-dioxane, was detected in the groundwater in the area of study in 1986. This area, referred to in this investigation as the Western Plume, is one of several 1,4-dioxane plumes associated with the Pall/Gelman Sciences Inc. (P/GSI) site, an extensively investigated site of groundwater contamination.

1,4-Dioxane in the Western Plume area was initially believed to be the result of contaminated groundwater transported from a …


Multiple Isotopic Investigation Of Lake Sediments From Northern India, Alice Mwanda Jun 2002

Multiple Isotopic Investigation Of Lake Sediments From Northern India, Alice Mwanda

Masters Theses

Stable isotopes ratio of lake sediments can provide valuable environmental information. This possibility has been investigated using radiocarbon dated fossil lake sediments from the Himalayan region of Northern India. The chronology was established using Radiocarbon dating of both organic and inorganic fractions using (AMS). Inorganic ages are older than organic ages. Organic ages are expected to increase stratigraphically, however several anomalous old ages are found in the younger part of the sediments. Final chronology, determined using selected sensible ages identified two periods of sedimentation. The high sedimentation period is characterized by sedimentation rate of 0.8cm/yr and it fairly coincides with …


Rock Glacier Surface Motion In Beacon Valley, Antarctica, From Synthetic-Aperture Radar Interferometry, Andrew G. Fountain, Eric Rignot, Bernard Hallet Jun 2002

Rock Glacier Surface Motion In Beacon Valley, Antarctica, From Synthetic-Aperture Radar Interferometry, Andrew G. Fountain, Eric Rignot, Bernard Hallet

Geology Faculty Publications and Presentations

We present radar interferograms of rock glaciers in the Beacon Valley sector of the McMurdo Dry Valleys, in East Antarctica, as part of a comprehensive study of surface processes in the area. Due to the relative absence of net precipitation (snow) in this region and the stability of the surface, the rock glaciers maintain excellent coherence of the radar returns over several years. As a result, we obtain a spatially continuous surface velocity field with a precision of fractions of a millimeter per year. On distinct rock glaciers entering Beacon Valley, we find coherent velocity patterns, with peak velocities approaching …


Mapping The Volumetric Soil Water Content Of A California Vineyard Using High-Frequency Gpr Ground Wave Data, Susan Sharpless Hubbard, Katherine R. Grote, Yoram N. Rubin Jun 2002

Mapping The Volumetric Soil Water Content Of A California Vineyard Using High-Frequency Gpr Ground Wave Data, Susan Sharpless Hubbard, Katherine R. Grote, Yoram N. Rubin

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

An attempt was made to establish the utility of ground-penetrating radar (GPR) as a quick and noninvasive field tool for shallow soil water content estimates as a function of space and time. Initially, detailed studies of collocated data, with electromagnetic velocity estimates from GPR data compared to gravimetric measurements of water content and to soil testure were carried out. Using the procedures developed during the detailed studies, full grids of GPR data were collected over the entire site several times. Data obtained indicate that incorporation of multiple frequency GPR grids can provide high-resolution estimates of soil water content variations as …


Gravity Evidence For A Larger Limpopo Belt In Southern Africa And Geodynamic Implications, Rubeni T. Ranganai, Ali Basira H. Kampunzu, Estella A. Atekwana, B. K. Paya, J. G. King, D. I. Koosimile, Edgar H. Stettler Jun 2002

Gravity Evidence For A Larger Limpopo Belt In Southern Africa And Geodynamic Implications, Rubeni T. Ranganai, Ali Basira H. Kampunzu, Estella A. Atekwana, B. K. Paya, J. G. King, D. I. Koosimile, Edgar H. Stettler

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Limpopo Belt of southern Africa is a Neoarchean orogenic belt located between two older Archean provinces, the Zimbabwe craton to the north and the Kaapvaal craton to the south. Previous studies considered the Limpopo Belt to be a linearly trending east-northeast belt with a width of ∼250 km and ∼600 km long. We provide evidence from gravity data constrained by seismic and geochronologic data suggesting that the Limpopo Belt is much larger than previously assumed and includes the Shashe Belt in Botswana, thus defining a southward convex orogenic arc sandwiched between the two cratons. The 2 Ga Magondi orogenic …