Digital Commons Network^™

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 …

A Middle Pleistocene Age And Biogeography For The Extinct Rodent Megalomys Curazensis From Curaçao, Netherlands Antilles, Donald A. Mcfarlane, Joyce Lundberg

WM Keck Science Faculty Papers

The extinct oryzomyine rodent Megalomys curazensis has been known from abundant but fragmentary remains on the island of Curaçao since 1959. Here we demonstrate an age of 130 000 to 400 000 years before present based on geomorphological context, and propose a biogeographical model for the genus.

Pharmaceuticals, Hormones, And Other Organic Wastewater Contaminants In U.S. Streams, 1999-2000: A National Reconnaissance, Dana Kolpin, Edward Furlong, Michael Meyer, E. Michael Thurman, Steven Zaugg, Larry Barber, Herbert Buxton

United States Geological Survey: Staff Publications

To provide the first nationwide reconnaissance of the occurrence of pharmaceuticals, hormones, and other organic wastewater contaminants (OWCs) in water resources, the U.S. Geological Survey used five newly developed analytical methods to measure concentrations of 95 OWCs in water samples from a network of 139 streams across 30 states during 1999 and 2000. The selection of sampling sites was biased toward streams susceptible to contamination (i.e. downstream of intense urbanization and livestock production). OWCs were prevalent during this study, being found in 80% of the streams sampled. The compounds detected represent a wide range of residential, industrial, and agricultural origins …

Holocene Multidecadal And Multicentennial Droughts Affecting Northern California And Nevada, Larry Benson, Michaele Kashgarian, Robert Rye, Steve Lund, Fred Paillet, Joseph Smoot, Cynthia Kester, Scott Mensing, Dave Meko, Susan Landström

United States Geological Survey: Staff Publications

Continuous, high-resolution δ¹⁸O records from cored sediments of Pyramid Lake, Nevada, indicate that oscillations in the hydrologic balance occurred, on average, about every 150 years (yr) during the past 7630 calendar years (cal yr). The records are not stationary; during the past 2740 yr, drought durations ranged from 20 to 100 yr and intervals between droughts ranged from 80 to 230 yr. Comparison of tree-ring-based reconstructions of climate change for the past 1200 yr from the Sierra Nevada and the El Malpais region of northwest New Mexico indicates that severe droughts associated with Anasazi withdrawal from Chaco Canyon …

Progress On Geoenvironmental Models For Selected Mineral Deposit Types, Robert R. Seal Ii, Nora K. Foley

United States Geological Survey: Publications

Since the beginning of economic geology as a subdiscipline of the geological sciences, economic geologists have tended to classify mineral deposits on the basis of geological, mineralogical, and geochemical criteria, in efforts to systematize our understanding of mineral deposits as an aid to exploration. These efforts have lead to classifications based on commodity, geologic setting (Cox and Singer, 1986), inferred temperatures and pressures of ore formation (Lindgren, 1933), and genetic setting (Park and MacDiarmid, 1975; Jensen and Bateman, 1979). None of these classification schemes is mutually exclusive; instead, there is considerable overlap among all of these classifications. A natural outcome …

Last Interglacial Climates, George J. Kukla, Michael L. Bender, Jacques-Louis De Beaulieu, Gerard Bond, Wallace S. Broecker, Piet Cleveringa, Joyce E. Gavin, Timothy D. Herbert, John Imbrie, Jean Jouzel, Lloyd D. Keigwin, Karen-Luise Knudsen, Jerry F. Mcmanus, Josef Merkt, Daniel R. Muhs, Helmut Muller, Richard Z. Poore, Stephen C. Porter, Guy Seret, Nicholas J. Shackleton, Charles Turner, Polychronis C. Tzedakis, Isaac J. Winograd

United States Geological Survey: Staff Publications

The last interglacial, commonly understood as an interval with climate as warm or warmer than today, is represented by marine isotope stage (MIS) 5e, which is a proxy record of low global ice volume and high sea level. It is arbitrarily dated to begin at approximately 130,000 yr B.P. and end at 116,000 yr B.P. with the onset of the early glacial unit MIS 5d. The age of the stage is determined by correlation to uranium–thorium dates of raised coral reefs. The most detailed proxy record of interglacial climate is found in the Vostok ice core where the temperature reached …

Bedrock Geology Of West Fork Quadrangle, Washington County, Arkansas, Jack T. King, Maria E. King, Stephen K. Boss

Journal of the Arkansas Academy of Science

A digital geologic map of West Fork quadrangle was produced at 1:24,000 scale using the geographic information system (GIS) software Maplnfo. Data regarding stratigraphic relations observed in the field were digitized onto the United States Geological Survey (USGS) digital raster graphic (DRG) of West Fork quadrangle. The geology of West Fork quadrangle consists of sedimentary rocks of the Mississippian and Pennsylvanian systems. The Fayetteville Shale and Pitkin Formation represent the Mississippian system. The Hale, Bloyd, and Atoka Formations represent the Pennsylvanian System. Each of these formations consists of members that were mapped at 1:24,000 scale, and this mapping effort represents …

Revised Bedrock Geology Of War Eagle Quadrangle, Benton County, Arkansas, Robert A. Sullivan, Stephen K. Boss

Journal of the Arkansas Academy of Science

A digital geologic map of War Eagle quadrangle (WEQ) was produced at the 1:24000 scale using the geographic information system (GIS) software ArcView® by digitizing geological contacts onto the United States Geological Survey (USGS) digital raster graphic (DRG). The geology of WEQ consists of sedimentary rocks of Ordovician (Cotter, Powell, and Everton Formations), Devonian (Clifty Formation and Chattanooga Shale), and Mississippian (St. Joe-Boone, Batesville, and Fayetteville Formations) systems. Impoundment of Beaver Lake in 1966 inundated most Ordovician rocks cropping out in WEQ, but all three formations were present in isolated outcrops along the present shoreline of the lake. The St. …

Early Holocene Change In Atmospheric Circulation In The Northern Great Plains: An Upstreamview Of The 8.2 Ka Cold Event, Walter E. Dean, Richard M. Forester, J. Platt Bradbury

United States Geological Survey: Staff Publications

Elk Lake, in northwestern Minnesota, contains numerous proxy records of climatic and environmental change contained in varved sediments with annual resolution for the last 10,000 years. These proxies show that about 8200 calendar years ago (8.2 cal. ka; 7300 radiocarbon years) Elk Lake went froma well-stratified lake that was wind-protected in a boreal forest to a well-mixed lake in open prairie savanna receiving northwesterly wind-blown dust, probably from the dry floor of Lake Agassiz. This change in climate marks the initiation of the widely recognized mid-Holocene “altithermal” in central North America. The coincidence of this change with the so-called 8.2 …

Baseline Limnology And Nutrient Study Of Basin Head Lagoon, Prince Edward Island, With Management Implications, Karen Connolly

Theses and Dissertations (Comprehensive)

Knowledge of physical and chemical process ongoing within an environment is an important step towards proper environmental management. Basin Head, Prince Edward Island is in the process of becoming a Marine Protected Area (MPA) and therefore a comprehensive management plan will need to be completed. The area contains a unique strain of Irish Moss (Chrondrus crispus Stackhouse) that is an important marine plant used in various industries. A study was conducted during the summer of 2000 to assess the basic physical and chemical conditions within the Basin Head Lagoon and surrounding stream inputs. The purpose of the study was to …

Structural And Sedimentary Characteristics Of The Tsergo Ri Rockslide Breccia, Langtang, Nepal, Himalaya, Mark B. Carpenter

Theses and Dissertations (Comprehensive)

The high magnitude Tsergo Ri landslide (c. 100ka), Langtang Himal, with a volume in excess of 15km^3 and a vertical displacement of more than 1500m remains the largest crystalline rockslide in Nepal Himalaya. The Quaternary landslide affected rocks in gneissic fancies of the High Himalayan Crystalline Sequence adjacent to the Tibetan Sedimentary Series. Depositional characteristics from exhumed transport slope sites were analysed at both the macroscopic and the microscopic scale to investigate (i) localised fracture in terms of orientation and density, and (ii) petrography of slide induced host rock deformation. Fracture orientation analysis indicate the spatial orientation of preexisting discontinuities …

Seiche Events At The Slave River Delta And Great Slave Lake, Northwest Territories: An Assessment Of Process And Impact, James Tobias Gardner

Theses and Dissertations (Comprehensive)

Seiche events are important hydrodynamic processes that impact the Slave River Delta, during the late summer and autumn. Given the scarcity of previous research on seiche events at river deltas and the physical dimensions and orientation of the Slave River Delta, this location at the southern shore of Great Slave Lake is ideal to study the occurrence and impacts of seiche events at a river delta. Seasonal changes to long-term water level trends and water level variability on Great Slave Lake, correspond to changes to the Slave River flow potentially associated with the impacts of regulation of the Peace River. …

Investigating Spatio-Temporal Variability Of Hydrological Components In The Canadian Rockies (Alberta), Christopher Dennis Hopkinson

Theses and Dissertations (Comprehensive)

This thesis addresses two questions related to the broad topic of mountain hydrology: 1) How do interannual hydrological balancee and pathway components vary in complex temperate high mountain environments at various spatio-temporal scales? 2) a) Is it possible, using dedicated hydrological models, for significant errors in simulated runoff components despite good hydrograph recreations (i.e. right results for wrong reasons)? b) If so, what kinds of errors are encountered? The first question was addressed by undertaking a hydrological tracer and hydrometric study at three basin scales (Banff —2200 km2, Lake Louise —400 km2 and the headwaters —30 km2) within the Bow …

Cave Breakdown By Vadose Weathering, R. A. L. Osborne

International Journal of Speleology

Vadose weathering is a significant mechanism for initiating breakdown in caves. Vadose weathering of ore bodies, mineral veins, palaeokarst deposits, non-carbonate keystones and impure, altered or fractured bedrock, which is intersected by caves, will frequently result in breakdown. Breakdown is an active, ongoing process. Breakdown occurs throughout the vadose zone, and is not restricted to large diameter passages, or to cave ceilings. The surfaces of disarticulated blocks are commonly coated, rather than having fresh broken faces, and blocks continue to disintegrate after separating from the bedrock. Not only gypsum, but also hydromagnesite and aragonite are responsible for crystal wedging. It …

Dune Morphology Response To Water Level Change, Pinery Provincial Park, Ontario, Canada, Michael C.A. Bitton

Theses and Dissertations (Comprehensive)

This thesis describes the geomorphological changes to a trough blowout in Pinery Provincial Park's sand dunes. The Park is located on Lake Huron’s southeastern shore where, due to rapid changes in Lake Huron water levels, a study could be completed examining the changes to blowout morphology based on the change in beach sediment supply. The study took place during relative low Lake Huron levels (1999-2000) and was compared to data collected during a period of relative high Lake Huron levels (1994-1995). Field research included erosion pin measurement to monitor and verify morphological change through the throat of the blowout, aeolian …

Glacial Deposits, Vol. 30, 2001-2002, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology

From Sand To Sandstone: Documenting The Total Change During Diagenesis, Wilfrido Solano-Acosta

All-Inclusive List of Electronic Theses and Dissertations

The objective of this study is to provide a more comprehensive picture of sandstone diagenesis from a different perspective; starting from an analog sand serving as a precursor of a lithified sandstone.

The Petrology And Geochemistry Of Volcán Huaynaputina, Southern Peru, Steven R. Schubring

All-Inclusive List of Electronic Theses and Dissertations

The 1600 eruption of Vol can Huaynaputina in Southern Peru was one of the largest historic eruptions (VEl 6). The eruption proceeded in three stages containing the same mineral assemblage of plagioclase>homblende>biotite> Fe-Ti oxides±apatite. Differences in crystal content, vesicularity, volatile content, temperature estimates, and the presence of disequilibrium textures have brought into question the petrogenesis of the 1600 eruption products. This work strives to quantify the pre- and syn-eruption magmatic conditions in order to ascertain the petrogenesis of the eruption products. Stage I was less evolved(~ 73% Si02), volatile rich (:S 5.3% H20), crystal poor (17- 26 wt. …

1998 Debris Flows Near The Yakima River, Kittitas County, Washington—Some Geomorphic Implications, Martin R. Kaatz

Geography Faculty Scholarship

The geomorphic consequences of debris flows and their asso- ciated storms have been documented in many parts of the United States. Few, if any, have been studied and documented in central Washington. The importance of recurrent debris flows in sculpting Washington landscapes has not been generally recognized compared to other processes. Arid and semi-arid regions are particularly vulnerable to debris flows triggered by sudden intense thunderstorms. Most such areas are sparsely populated and eyewitnesses are uncommon. By contrast, semi-arid central Washington is relatively well popu- lated, and there are likely to be people who have observed the storms. Such witnesses …

Application Of Morphometric Relationships To Active Flow Networks Within The Mammoth Cave Watershed, John Glennon

Masters Theses & Specialist Projects

Numerous quantitative relationships have been formulated to describe the nature of surface-drainage networks. These parameters have been used in various studies of geomorphology and surface-water hydrology, such as flood characteristics, sediment yield, and evolution of basin morphology. Little progress has been made in applying these quantitative descriptors to karst flow systems due to the lack of sufficiently complete data and inadequate technology for processing the large, complex data sets. However, as a result of four decades of investigation, an abundance of data now exists for the Mammoth Cave Watershed providing the opportunity for broader quantitative research in the organization of …

The Role Of Small And Medium Enterprises In The Economy Of Slovakia, Jaroslav Kling

Student Work

The aim of this paper is to analyze the role of small and medium enterprises in the economy of Slovakia. The changes of 1989 brought about the changes of society and economy as well. In the period of transformation of the Slovak economy, small and medium enterprises have been often considered to be a critical element of economic revival. The study answers to what extent this expectation has been met. Legal and institutional frameworks of the small and medium enterprises development are analyzed. Popular attitudes toward entrepreneurs, views and opinions of the key representatives of entrepreneurs and state representatives are …

Orbitally Induced Oscillations In The East Antarctic Ice Sheet At The Oligocene/Miocene Boundary, Tim R. Naish, Ken J. Woolfe, Peter J. Barrett, Gary S. Wilson, Cliff Atkins, Steven M. Bohaty, Christian J. Bücker, Michele Claps, Fred J. Davey, Gavin B. Dunbar, Alistair G. Dunn, Christopher R. Fielding, Fabio Florindo, Michael J. Hannah, David M. Harwood, Stuart A. Henrys, Lawrence A. Krissek, Mark Lavelle, Jaap Van Der Meer, William C. Mcintosh, Frank Niessen, Sandra Passchier, Ross D. Powell, Andrew P. Roberts, Leonardo Sagnotti, Reed P. Scherer, C. Percy Strong, Franco Talarico, Kenneth L. Verosub, Giuliana Villa, David K. Watkins, Peter-N. Webb, Thomas Wonik

Department of Earth and Atmospheric Sciences: Faculty Publications

Between 34 and 15 million years (Myr) ago, when planetary temperatures were 3-4°C warmer than at present and atmospheric CO₂ concentrations were twice as high as today, the Antarctic ice sheets may have been unstable. Oxygen isotope records from deep-sea sediment cores suggest that during this time fluctuations in global temperatures and high-latitude continental ice volumes were influenced by orbital cycles. But it has hitherto not been possible to calibrate the inferred changes in ice volume with direct evidence for oscillations of the Antarctic ice sheets. Here we present sediment data from shallow marine cores in the western Ross …

Earth News, V25, Fall 2001, Department Of Earth Science, University Of Northern Iowa.

Earth News

Inside this issue:

--- News from the Department Head
--- Earth Science Staff Activities
--- Earth Science Majors
--- 2001 Earth Science Graduates
--- Student Research Presentations
--- Student Internships
--- STORM: Science center for Teaching, Outreach, and Research on Meteorology
--- Studies in the Geology of Iowa for Teachers
--- Earth Science Student Assistants
--- Sigma Gamma Epsilon - Gamma Sigma Chapter
--- Gifts to the Department of Earth Science
--- 2001-2002 Scholarship and Award Recipients
--- 2001 Spring Trip Summary
--- Earth Science Seminar Series
--- Rapa Nui Expedition - March 2000
--- Alumni Profile - Larry J. …

Validation Of Land Surface Models Using Satellite-Derived Surface Temperature, Joshua Rhoads, Ralph Dubayah, Dennis Lettenmaier, Greg O'Donnell, Venkataraman Lakshmi

Faculty Publications

This research examines the feasibility of using remotely sensed surface temperature for validation and updating of land surface hydrologic models. Surface temperature simulated by the Variable Infiltration Capacity (VIC) hydrologie model is compared over the Arkansas-Red River basin with surface temperature retrievals from TOVS and GOES. The results show that modeled and satellite-derived surface temperatures agree well when aggregated in space or time. In particular, monthly mean temperatures agree on the pixel scale, and basin mean temperatures agree instantaneously. At the pixel scale, however, surface temperatures from both satellites were found to have higher spatial and temporal variabilities than the …

C-Band Sar Backscatter Characteristics Of Arctic Sea And Land Ice During Winter, Konrad Steffen, John Heinrichs

Geosciences Faculty Publications

Synthetic Aperture Radar (SAR) data has become an important tool for studies of polar regions, due to high spatial resolution even during the polar night and under cloudy skies. We have studied the temporal variation of sea and land ice backscatter of twenty-four SAR images from the European Remote Sensing satellite (ERS-1) covering an area in Lady Ann Strait and Jones Sound, Nunavut, from January to March 1992. The presence of fast ice in Jones Sound and glaciers and ice caps on the surrounding islands provides an ideal setting for temporal backscatter studies of ice surfaces. Sample regions for eight …

Experimental Diatom Dissolution And The Quantification Of Microfossil Preservation In Sediments, D. B. Ryves, S. Juggins, Sherilyn C. Fritz, R. W. Battarbee

Department of Earth and Atmospheric Sciences: Faculty Publications

Four laboratory experiments on fresh, modern diatoms collected from lakes in the Northern Great Plains of North America were carried out to assess the effects of dissolution on diatom abundance and composition. Marked differences in mean dissolution susceptibility exist between species, despite sometimes significant intra- specific variation between heterovalves. Twenty-four taxa were ranked according to susceptibility to dissolution using an exponential decay model of valve abundance. This dissolution ranking was used to derive two weighted indices of sample preservation. A third index (F) was based on a simple binary classification of valve morphology into dissolved and pristine categories, …

Puerto Rican Karst - A Vital Resource, Ariel E. Lugo, Leopoldo Miranda Castro, Abel Vale, Tania Del Mar López, Enrique Hernández Prieto, Andrés García Martinó, Alberto R. Puente Rolón, Adrianne G. Tossas, Donald A. Mcfarlane, Tom Miller, Armando Rodríguez, Joyce Lundberg, John Thomlinson, José Colón, Johannes H. Schellekens, Olga Ramos, Eileen Helmer

WM Keck Science Faculty Papers

The limestone region of Puerto Rico covers about 27.5 percent of the island's surface and is subdivided into the northern, southern, and dispersed limestone areas. All limestone areas have karst features. The karst belt is that part of the northern limestone with the most spectacular surficial karst landforms. It covers 142,544 ha or 65 percent of the northern limestone. The karst belt is the focus of this publication, although reference is made to all limestone regions. The northern limestone contains Puerto Rico's most extensive freshwater aquifer, largest continuous expanse of mature forest, and largest coastal wetland, estuary, and underground cave …

Dye Tracing To Delineate Drainage Basins And Determine Groundwater Sensitivity, Mammoth Cave, Kentucky; With Special Reference To Potential Groundwater Contamination From Spills Along Interstate I-65, Arthur Capps

Masters Theses & Specialist Projects

The Mammoth Cave System of south central Kentucky encompasses more than 560 km of surveyed cave passages. The largest groundwater basin (244 km2) found within this cave system emerges from the Turnhole Bend Spring on the Green River. During high flow conditions, water from this groundwater basin will spill over into the Echo River section of the cave. Previous research, including cave mapping and dye tracing (Quinlan and Ray, 1989; Currens and Ray, 1998; Coons, 1994), has delineated the boundaries of spring groundwater basins for numerous springs along the Green and Barren Rivers. These data showed that 60% of the …

The Search For A Meteorite Concentration Mechanism In The Allan Hills Icefields, Luke Probst

Honors Capstones

Capstone submitted as a graduation requirement for the BSU Honors Program.

Management Of Soil Organic Matter And Gypsum For Sustainable Production In The Carnarvon Horticultural District Of Western Australia, R.S.B. Greene, A.J. Lin, D. C. Parr

Agriculture reports

Soil quality is critically important for the long-term production of high quality and high yielding fruit and vegetable crops in the Carnarvon horticultural district of Western Australia. A stable soil structure is essential for good soil quality.