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Temporal Analysis Of Floodplain Deposition Using Urban Pollution Stratigraphy, Wilson Creek, Sw Missouri, Kathy A. Shade Jan 2003

Temporal Analysis Of Floodplain Deposition Using Urban Pollution Stratigraphy, Wilson Creek, Sw Missouri, Kathy A. Shade

Graduate Theses/Dissertations

Alluvial sediments record both hydrologic changes and variations of sediment quality affecting watersheds. This study uses urban pollution signatures as temporal tracers to date alluvial deposits along Wilson Creek located within Wilson’s Creek National Battlefield Park in southwestern Missouri. The creek drains Springfield, the third largest city in the state, which was settled in 1833. This study has three main objectives: (1) review historical documents to develop a pollution history for the watershed; (2) determine if there is a correlation between heavy metal and phosphorus concentrations in sediment cores and the timing of release of those elements into the creek …


Channel Geomorphology And Restoration Guidelines For Springfield Plateau Streams, South Dry Sac Watershed, Southwest Missouri, John M. Horton Jan 2003

Channel Geomorphology And Restoration Guidelines For Springfield Plateau Streams, South Dry Sac Watershed, Southwest Missouri, John M. Horton

Graduate Theses/Dissertations

Land-use change, both historical and present, has been a source of channel degradation within Ozark streams. This study examines the influence of land use on channel morphology within the South Dry Sac Watershed which drains 78.5 km2. The main objectives of this study are to: (1) perform a geomorphic assessment of stream channel and sediment characteristics; (2) evaluate the effects of watershed factors on channel morphology and dynamics; (3) quantify the geomorphic relationships for use in stream restoration projects in the Springfield Plateau area. Thirty-six reaches were surveyed and evaluated in the field for channel cross-sectional geometry, longitudinal profile, and …


History Of Sedimentation And Contamination In Valley Mill Reservoir, Springfield, Missouri, Susan S. Licher Jan 2003

History Of Sedimentation And Contamination In Valley Mill Reservoir, Springfield, Missouri, Susan S. Licher

Graduate Theses/Dissertations

The Valley Mill Reservoir (VMR) was constructed between 1851 and 1871 and drains an important recharge area of the drinking water watershed for Springfield, Missouri. Presently, management efforts to protect downstream water quality are aimed at using VMR as a non-point pollution and sedimentation basin since its watershed is planned for continued urban development. The morphometry of VMR is typical of most reservoirs with an elongated basin and the deepest point being near the dam. Sedimentation within the reservoir has created a delta formation with upstream wetlands and floodplains acting as part of the delta especially during the past. Little …


Last Glacial Loess In The Conterminous Usa, E. Arthur Bettis Iii, Daniel R. Muhs, Helen M. Roberts, Ann G. Wintle Jan 2003

Last Glacial Loess In The Conterminous Usa, E. Arthur Bettis Iii, Daniel R. Muhs, Helen M. Roberts, Ann G. Wintle

United States Geological Survey: Staff Publications

The conterminous United States contains an extensive and generally well-studied record of Last Glacial loess. The loess occurs in diverse physiographic provinces, and under a wide range of climatic and ecological conditions. Both glacial and non-glacial loess sources are present, and many properties of the loess vary systematically with distance from loess sources. United States’ mid-continent Last Glacial loess is probably the thickest in the world, and our calculated mass accumulation rates (MARs) are as high as 17,500 g/m2/yr at the Bignell Hill locality in Nebraska, and many near-source localities have MARs greater than 1500 g/m2/yr. …


Long-Lived Pluvial Episodes During Deposition Of The Navajo Sandstone, David B. Loope, Clinton M. Rowe Jan 2003

Long-Lived Pluvial Episodes During Deposition Of The Navajo Sandstone, David B. Loope, Clinton M. Rowe

Department of Earth and Atmospheric Sciences: Faculty Publications

The Navajo Sandstone of the American Southwest was deposited at approximately 190 Ma in a giant, subtropical dune field near the western margin of Pangea. From this unit, we report thick intervals of dune cross-strata that were churned by insects and trampled by reptiles. Although dunes continued to migrate freely, the distribution of trace fossils shows that plant life in wet interdune areas sustained high levels of animal activity on the dunes for many thousands of years. We interpret this suite of structures as the record of a pluvial episode climatologically similar to the period of “greening” in the Sahara …


Intercontinental Migration Of Large Mammalian Carnivores: Earliest Occurrence Of The Old World Beardog Amphicyon (Carnivora, Amphicyonidae) In North America, Robert M. Hunt Jr. Jan 2003

Intercontinental Migration Of Large Mammalian Carnivores: Earliest Occurrence Of The Old World Beardog Amphicyon (Carnivora, Amphicyonidae) In North America, Robert M. Hunt Jr.

Department of Earth and Atmospheric Sciences: Faculty Publications

North American amphicyonid carnivorans are prominent members of the mid-Cenozoic terrestrial carnivore community during the late Eocene to late Miocene (Duchesnean to Clarendonian). Species range in size from <5 kg to >200 kg. Among the largest amphicyonids are Old and New World species of the genus Amphicyon: A. giganteus in Europe (18–~15? Ma) and Africa, A. ingens in North America (15.9–~14.2 Ma). Amphicyon first appears in the Oligocene of western Europe, surviving there until the late Miocene. Migration to Africa and North America takes place in the early Miocene. The genus occurs in the Arrisdrift fauna (Namibia) of southwest Africa, indicating migration south …


Eolian Sand Transport Pathways In The Southwestern United States: Importance Of The Colorado River And Local Sources, Daniel R. Muhs, Richard L. Reynolds, Josh Been, Gary Skipp Jan 2003

Eolian Sand Transport Pathways In The Southwestern United States: Importance Of The Colorado River And Local Sources, Daniel R. Muhs, Richard L. Reynolds, Josh Been, Gary Skipp

United States Geological Survey: Staff Publications

Geomorphologists have long recognized that eolian sand transport pathways extend over long distances in desert regions. Along such pathways, sediment transport by wind can surmount topographic obstacles and cross major drainages. Recent studies have suggested that three distinct eolian sand transport pathways exist (or once existed) in the Mojave and Sonoran Desert regions of the southwestern United States. One hypothesized pathway is eolian sand transport from the eastern Mojave Desert of California into western Arizona, near Parker, and would require sand movement across what must have been at least a seasonally dry Colorado River valley. We tested this hypothesis by …


Where Are The Women Geoscience Professors?, Mary Anne Holmes, Suzanne O'Connel Jan 2003

Where Are The Women Geoscience Professors?, Mary Anne Holmes, Suzanne O'Connel

Department of Earth and Atmospheric Sciences: Faculty Publications

Compiles an extensive set of data on the status of women in the geosciences, identifying successful strategies for increasing diversity as well as obstacles that hinder efforts. The lessons learned and best practices that arise from this report will help geoscientists continue to increase the gender diversity of their community. Some of these lessons also provide insight into ways to improve the racial and ethnic diversity of the geosciences.


Influence Of The Pacific Decadal Oscillation On The Climate Of The Sierra Nevada, California And Nevada, Larry Benson, Braddock Linsley, Joe Smoot, Scott Mensing, Steve Lund, Scott Stine, Andre Sarna-Wojcicki Jan 2003

Influence Of The Pacific Decadal Oscillation On The Climate Of The Sierra Nevada, California And Nevada, Larry Benson, Braddock Linsley, Joe Smoot, Scott Mensing, Steve Lund, Scott Stine, Andre Sarna-Wojcicki

United States Geological Survey: Staff Publications

Mono Lake sediments have recorded five major oscillations in the hydrologic balance between A.D. 1700 and 1941. These oscillations can be correlated with tree-ring-based oscillations in Sierra Nevada snowpack. Comparison of a tree-ring-based reconstruction of the Pacific Decadal Oscillation (PDO) index (D’Arrigo et al., 2001) with a coral-based reconstruction of Subtropical South Pacific sea-surface temperature (Linsley et al., 2000) indicates a high degree of correlation between the two records during the past 300 yr. This suggests that the PDO has been a pan-Pacific phenomena for at least the past few hundred years. Major oscillations in the hydrologic balance of the …


Aeolian Cliff-Top Deposits And Buried Soils In The White River Badlands, South Dakota, Usa, J. Elmo Rawling Iii, Glen G. Fredlund, Shannon Mahan Jan 2003

Aeolian Cliff-Top Deposits And Buried Soils In The White River Badlands, South Dakota, Usa, J. Elmo Rawling Iii, Glen G. Fredlund, Shannon Mahan

United States Geological Survey: Staff Publications

Aeolian deposits in the North American Great Plains are important sources of Holocene palaeoenvironmental records. Although there are extensive studies on loess and dune records in the region, little is known about records in aeolian cliff-top deposits. These are common on table (mesa) edges in the White River Badlands. These sediments typically have loam and sandy-loam textures with dominantly very fine sand, 0.5–1% organic carbon and 0.5–5% CaCO3. Some of these aeolian deposits are atypically coarse and contain granules and fine pebbles. Buried soils within these deposits are weakly developed with A-C and A-AC-C profiles. Beneath these are …


Quaternary Loess-Paleosol Sequences As Examples Of Climate-Driven Sedimentary Extremes, Daniel R. Muhs, E. Arthur Bettis Iii Jan 2003

Quaternary Loess-Paleosol Sequences As Examples Of Climate-Driven Sedimentary Extremes, Daniel R. Muhs, E. Arthur Bettis Iii

United States Geological Survey: Staff Publications

Loess is a widespread, wind-transported, silt-dominated deposit that contains geologic archives of atmospheric circulation and paleoclimate on continents. Loess may cover as much as 10% of the Earth’s land surface. It is composed mainly of quartz, feldspars, and clay minerals, with varying amounts of carbonate minerals. The geochemistry of loess differs from region to region, depending on source materials, but all loess is very high in SiO2 with lesser amounts of other major elements. Trends in loess downwind from source areas include systematic decreases in thickness and amounts of sand and coarse silt, and increases in amounts of fine silt …


Variability Of Metals In Soils In The Sudbury Area (Ontario), Vera Spektor Jan 2003

Variability Of Metals In Soils In The Sudbury Area (Ontario), Vera Spektor

Theses and Dissertations (Comprehensive)

Industrial development influences the natural and human environment. At the local scale, the most intensive industrial pollution is in the area of factories and industrial centers. Industrial pollution is concentrated in soil and vegetation (then, using water systems and trophic chains it may enter all ecosystem components). The industrial pollution of the Sudbury region includes mostly sulfur dioxide and heavy metals. The main goal of this study was to examine spatial variability in metal distribution in soil for the Sudbury area. Objectives of the work were to describe metal distribution depending on geographic factors such as topographic location, vegetation cover, …


Quantifying Ecosystem Geomorphology Of The Southern Appalachian Mountains, Scott R. Abella Jan 2003

Quantifying Ecosystem Geomorphology Of The Southern Appalachian Mountains, Scott R. Abella

Public Policy and Leadership Faculty Research

Geomorphology is a dominant factor influencing vegetation distribution in the southern Appalachians, and quantifying landform characteristics is increasingly important for forest ecosystem classification. This study used slope gradient and two previously published geomorphic indices, terrain shape index and landform index that quantify landform shape and protection, to develop a field-based landform quantification system at four study areas in the southern Appalachians. Six major landform types (ridgetops, nose slopes, linear hillslopes, coves, stream ravines, and stream bottoms) exhibited quantitatively different characteristics, and these differences among landforms were not evident when using only categorical landform descriptions (e.g., convex, concave) that have been …


Late Miocene-Pliocene Detachment Faulting And Pliocene-Recent Basin-And-Range Extension Inferred From Dismembered Rift Basins Of The Salt Lake Formation, Se Idaho, Susanne U. Janecke, S. M. Carney, M. E. Perkins, J. C. Evans, P. K. Link, R. Q. Oaks Jr., B. P. Nash Jan 2003

Late Miocene-Pliocene Detachment Faulting And Pliocene-Recent Basin-And-Range Extension Inferred From Dismembered Rift Basins Of The Salt Lake Formation, Se Idaho, Susanne U. Janecke, S. M. Carney, M. E. Perkins, J. C. Evans, P. K. Link, R. Q. Oaks Jr., B. P. Nash

Geosciences Faculty Publications

Geologic mapping, basin analysis, and tephra correlations in the Clifton and Malad City East 7.5-minute quadrangles in southeastern Idaho indicate that the modern Basin-and-Range topography is only a few million years old and was superimposed on unrelated rift basins associated with the ~12 to < 4 Ma Bannock detachment system. The Miocene-Pliocene Salt Lake Formation in the greater Cache Valley area was deposited during three sub-episodes of west-southwest extension on the Bannock detachment system.

Depositional systems within the Salt Lake Formation (>10.27 ± 0.07 Ma to < 5.1-4.4 Ma) evolved in response to the changing structural configuration of rift basins in the hanging wall of the Bannock detachment system. Early alluvial fans derived from the underlying Paleozoic rocks were replaced by broad, saline/alkaline lakes during the translation phase on the detachment fault. Later, as the hanging wall broke up internally, freshwater lakes and deltas occupied newly created NE-tilted half graben, and eventually filled them with braided streams. The Bannock detachment system collapsed the Cache-Pocatello Culmination of the dormant Sevier fold-and-thrust belt, much like the Sevier Desert Detachment collapsed the Sevier Culmination and the Wasatch Fault collapsed the Wasatch Culmination.

Deposition and tilting of the Salt Lake Formation ceased in the middle to late Pliocene (< 2 >Ma?) before uplift of the Clifton Horst along a new system of Basin-and-Range normal faults. This later episode of normal faulting uplifted and exposed metamorphic rocks in …


New Evidence For Enhanced Ocean Primary Production Triggered By Tropical Cyclone, I. Lin, W. Timothy Liu, Chun-Chieh Wu, George T. F. Wong, Chuanmin Hu, Zhiqiang Chen, Wen-Der Liang, Yih Yang, Kon-Kee Liu Jan 2003

New Evidence For Enhanced Ocean Primary Production Triggered By Tropical Cyclone, I. Lin, W. Timothy Liu, Chun-Chieh Wu, George T. F. Wong, Chuanmin Hu, Zhiqiang Chen, Wen-Der Liang, Yih Yang, Kon-Kee Liu

OES Faculty Publications

[1] New evidence based on recent satellite data is presented to provide a rare opportunity in quantifying the long-speculated contribution of tropical cyclones to enhance ocean primary production. In July 2000, moderate cyclone Kai-Tak passed over the South China Sea (SCS). During its short 3-day stay, Kai-Tak triggered an average 30-fold increase in surface chlorophyll-a concentration. The estimated carbon fixation resulting from this event alone is 0.8 Mt, or 2-4% of SCS's annual new production. Given an average of 14 cyclones passing over the SCS annually, we suggest the long-neglected contribution of tropical cyclones to SCS's annual new production may …


The Relationships Of Vegetation And Bird Communities With Landforms And Geomorphic Processes On The Central Niagara Escarpment (Ontario), Robert John Milne Jan 2003

The Relationships Of Vegetation And Bird Communities With Landforms And Geomorphic Processes On The Central Niagara Escarpment (Ontario), Robert John Milne

Theses and Dissertations (Comprehensive)

This study has examined the relationships between geomorphic form and process, vegetation composition and dynamics, and avian populations for landscapes in the central Niagara Escarpment, Southern Ontario. This includes an area extending from Speyside Conservation area near Milton to Mono Cliffs Provincial Park north of Orangeville. Data was collected for geomorphic form and process parameters, vegetation species and structural parameters, and avian species. The physical parameters included a combination of landform characteristics including slope angle, aspect, and landscape position and geomorphic processes, such as creep and debris slides, measured as a level of disturbance. Human levels of disturbance were also …


Glacial Deposits, Vol. 31, 2002-2003, Department Of Geography-Geology Jan 2003

Glacial Deposits, Vol. 31, 2002-2003, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


Lake-Catchment Interactions With Climate In The Low Arctic Of Southern West Greenland, N. John Anderson, Sherilyn C. Fritz, Christopher E. Gibson, Bent Hasholt, Melanie J. Leng Dec 2002

Lake-Catchment Interactions With Climate In The Low Arctic Of Southern West Greenland, N. John Anderson, Sherilyn C. Fritz, Christopher E. Gibson, Bent Hasholt, Melanie J. Leng

Department of Earth and Atmospheric Sciences: Faculty Publications

Arctic hydrology plays a central role in the earth’s heat balance and ocean circulation (Vörösmarty et al. 2001). Future changes associated with human influence on the climate system are also predicted to cause major changes in the energy and hydrologic mass balance of Arctic catchments. Climate change will likely affect permafrost and snowmelt, which dominate Arctic hydrology and control the chemistry of surface runoff (and hence streams and lakes) as water percolates through the active layer. However, the controls and dynamic impact of snowmelt are poorly understood, because this critical timeframe is often missed by sampling programs. In the Søndre …


Ua66/8/3 Geogram, Wku Geography & Geology Oct 2002

Ua66/8/3 Geogram, Wku Geography & Geology

WKU Administration Documents

Newsletter created by and about the WKU Geography & Geology highlighting activities of faculty, students and alumni.


Karst Aquifers As Atmospheric Carbon Sinks: An Evolving Global Network Of Research Sites, Chris Groves, Joe Meiman, Joel Despain, Liu Zaihua, Daoxin Yuan Aug 2002

Karst Aquifers As Atmospheric Carbon Sinks: An Evolving Global Network Of Research Sites, Chris Groves, Joe Meiman, Joel Despain, Liu Zaihua, Daoxin Yuan

Earth, Environmental, and Atmospheric Sciences Faculty Publications

Karst flow systems formed in carbonate rocks have been recognized as a sink for atmospheric carbon that originates as gaseous carbon dioxide and ends up as dissolved aqueous carbon, primarily as bicarbonate. While measurements of the magnitude of the sink associated with carbonate rock dissolution have assumed that half of the dissolved inorganic carbon leaving a given catchment comes from the mineral and half from the atmosphere, consideration of the kinetics of carbonate mineral dissolution in acid solutions suggests that the ratio is enriched in mineral-source carbon to an extent that depends on the geochemical environment of mineral/fluid contact. After …


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 …


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 …


Transport Of The Herbicide Atrazine On Suspended Sediments During A Spring Storm Event In Mammoth Cave, Kentucky, Michael Anderson May 2002

Transport Of The Herbicide Atrazine On Suspended Sediments During A Spring Storm Event In Mammoth Cave, Kentucky, Michael Anderson

Masters Theses & Specialist Projects

This study examines the transport of atrazine, an herbicide used in Kentucky to control grassy and broad-leaf weeds in corn fields, on suspended sediments. Atrazine is a known carcinogen and endocrine disruptor and has been shown to be toxic at low environmental concentrations. Atrazine has the capacity to adsorb to soil particles, which in karst areas such as those found in south central Kentucky can be transported directly into the groundwater. Suspended sediments and water were collected from a well at the Hawkins River in Mammoth Cave National Park during a spring storm and tested for atrazine. Atrazine was found …


A Macroterrain Landtype Association Classification Model For The Great Basin, Frank L. Dougher May 2002

A Macroterrain Landtype Association Classification Model For The Great Basin, Frank L. Dougher

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three Macroterrain Landtype Association classification models were developed to stratify and categorize Utah's West Desert. These models approached terrain segmentation using an energy-flow paradigm from erosional to transitional to depositional landscape. One model was developed as a slope-backed deterministic model that used slope-threshold limits to discriminate between Landtype Associations. A second model was developed as a stochastic, training-data driven supervised classification, using comparative t-values to classify the landscape to the most similar landtype class. The third model was a probabilistic algorithm, which classified the landscape to the most probable class based on multiple iterations of the stochastic model. These …


Application Of Biophysical Data To An Unsupervised Classification To Map Ecoregional Boundaries In The Desert Southwest, Paxton R. Mcclurg May 2002

Application Of Biophysical Data To An Unsupervised Classification To Map Ecoregional Boundaries In The Desert Southwest, Paxton R. Mcclurg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An unsupervised classification was applied to continuous biophysical variables in an attempt to delineate ecoregional boundaries in the desert southwest. Output was then compared with ecoregions delineated by the Natural Resources Conservation Service (NRCS), the Environmental Protection Agency (EPA), and the Forest Service at the national level. An attempt was made to use the same biophysical variables for input into the unsupervised classification as was emphasized by the various agencies with their ecoregional classifications at the desert level. Major constraints included data availability at such a large study area, data resolution, and data that were continuous. This eliminated categorical data …


Coalbed Methane Development In Wyoming’S Powder River Basin, Diana Hulme Apr 2002

Coalbed Methane Development In Wyoming’S Powder River Basin, Diana Hulme

Coalbed Methane Development in the Intermountain West (April 4-5)

21 pages (includes color illustrations and maps).

Contains endnotes.


A Gis To Select Plant Species For Erosion Control Along California Highways, Michael Curto, Brent Hallock, Misty Scharff Feb 2002

A Gis To Select Plant Species For Erosion Control Along California Highways, Michael Curto, Brent Hallock, Misty Scharff

Earth and Soil Sciences

Through road construction and maintenance activities, the California Department of Transportation (Caltrans) actively manages roadside rights-of-way that transect California's 41 million hectares (101 million acres), spanning over 3,000 meters of elevational change from seashore to subalpine. State and federal highways are grouped into 12 districts, each encompassing from one to 11 of the state's 58 counties. District personnel are typically responsible for implementing site-specific adaptations of general statewide guidelines for shortto long-term erosion control following construction or storm damage. Many erosion control projects involve reestablishing vegetation through seeding where the precarious life stages of germination and establishment are controlled by …


Mount Keumgang (Geography And History), Thomas Dolan Jan 2002

Mount Keumgang (Geography And History), Thomas Dolan

Faculty Bibliography

No abstract provided.


A New Megalonychid Sloth From The Late Wisconsinan Of The Dominican Republic, Elizabeth Rega, Donald A. Mcfarlane, Joyce Lundberg, Keith Christenson Jan 2002

A New Megalonychid Sloth From The Late Wisconsinan Of The Dominican Republic, Elizabeth Rega, Donald A. Mcfarlane, Joyce Lundberg, Keith Christenson

WM Keck Science Faculty Papers

An unusually well preserved skull, mandible, and indisputably associated post-cranial elements of new sloth, Acratocnus (Miocnus), were recovered from a cave in Jaragua National Park, Dominican Republic. The animal died lying in a rimstone pool and was rapidly coated with a thin calcite patina. We have documented a late Wisconsinan age for this specimen by inorganic 14C radiometric dating of the patina, with supporting data on the carbon systematics of the speleothems in this cave. This sloth is described as a new species on the basis of the distinctive morphology and relative size of cranial and mandibular features. We consider …