Earth Sciences Commons^™

Carbonates In Skeleton-Poor Seas: New Insights From Cambrian And Ordovician Strata Of Laurentia, Sara B. Pruss, Seth Finnegan, Woodward W. Fischer, Andrew H. Knoll

Geosciences: Faculty Publications

Calcareous skeletons evolved as part of the greater EdiacaranCambrian diversification of marine animals. Skeletons did not become permanent, globally important sources of carbonate sediment, however, until the Ordovician radiation. Representative carbonate facies in a Series 3 (510501 Ma) Cambrian to Tremadocian succession from western Newfoundland, Canada, and Ordovician successions from the Ibex area, Utah, USA, show that, on average, Cambrian and Tremadocian carbonates contain much less skeletal material than do post-Tremadocian sediments. Petrographic point counts of skeletal abundance within facies and proportional facies abundance in measured sections suggest that later Cambrian successions contain on average volume, whereas the skeletal content …

Modern And Late Holocene Wind Regimes Over The Great Plains (Central U.S.A.), Rebecca L. Schmeisser, David B. Loope, Joseph A. Mason

Department of Earth and Atmospheric Sciences: Faculty Publications

The Great Plains of the central United States contain numerous presently stabilized dune fields that were active during the late Holocene. The most recent period of reactivation occurred about 700–1000 years ago during the Medieval Climatic Anomaly, a period of frequent, severe drought recognized throughout the North American West. Dune orientations and internal bedding preserve information about paleowinds from this time period. We compared paleowind information with modern winds and potential sand transport analyzed from meteorological data. While both reconstructed paleowinds and modern winds include a strong northwesterly component over the northern to central portions of the Great Plains, a …

Coupled Carbon Isotopic And Sedimentological Records From The Permian System Of Eastern Australia Reveal The Response Of Atmospheric Carbon Dioxide To Glacial Growth And Decay During The Late Paleozoic Ice Age, Lauren P. Birgenheier, Tracy D. Frank, Christopher R. Fielding, Michael C. Rygel

Department of Earth and Atmospheric Sciences: Faculty Publications

Proxy geochemical records from high-latitude, ice-proximal deposits have the potential to provide key insights into past icehouse climates, but such records are rare. The Permian System of eastern Australia contains a rich record of environmental and climatic changes that occurred in areas proximal to glaciation during the acme and waning stages of the late Paleozoic ice age. Within this succession, a wealth of fine-grained, organic matter-rich facies provides an opportunity to construct a bulk δ¹³C_org record that records changes in atmospheric CO₂ through the Permian. Fluctuations in δ¹³C_org track changes in climate determined …

Timing Of Present And Future Snowmelt From High Elevations In Northwest Montana, Bonnie Jean Gillan, Joel T. Harper, Johnnie N. Moore

Geosciences Faculty Publications

The sensitivity of snowmelt-driven water supply to climate variability and change is difficult to assess in the mountain west, where strong climatic gradients coupled with complex topography are sampled by sparse ground measurements. We developed a model which ingests daily satellite imagery and meteorological data and is suitable for areas >1000 km2, yet captures spatial variability of snow accumulation and melt in steep mountain terrain.We applied the model for the years 2000–2008 to a 2900 km2 snowmelt-dominated watershed in NW Montana. We found that >25% of the basin’s snow water equivalent (SWE) accumulates above the highest measurement station and >70% …

Estimation Of Vertical Groundwater Fluxes Into A Streambed Through Continuous Temperature Profile Monitoring And The Relationship Of Groundwater Fluxes To Coaster Brook Trout Spawning Habitat , Matthew Van Grinsven

Dissertations, Master's Theses and Master's Reports - Open

We hypothesized that the spatial distribution of groundwater inflows through river bottom sediments is a critical factor associated with the selection of coaster brook trout (a life history variant of Salvelinus fontinalis,) spawning sites. An 80-m reach of the Salmon Trout River, in the Huron Mountains of the upper peninsula of Michigan, was selected to test the hypothesis based on long-term documentation of coaster brook trout spawning at this site. Throughout this site, the river is relatively similar along its length with regard to stream channel and substrate features. A monitoring well system consisting of an array of 27 …

Ordway Weather And Water Data 2010, Macalester College

Ordway Weather Data

Contains daily readings for the year indicated. The values include: PAR umol/s/m2, avg wind dir degree, avg windspeed mph, Avg Max Windspeed mph, Avg airtemp C, Avg RH %, Avg BP mmHg, Avg DailyRain in, Avg Rain Duration sec, Avg RainIntensity in/h, Avg Water Temp F, Avg sp cond mS/cm, avg pH, Avg Turb NTU+, Avg ODOSat %, Avg ODO mg/L, Water station PAR umol/s/m2, Avg Water Level m. File format: CSV.

Pseudokarst Of East Texas: Geomorphic Features And Evolution [Abstract], Kevin W. Stafford, Melinda G. Shaw-Faulkner, Wesley A. Brown

Faculty Presentations

No abstract provided.

Geochemical Spatial Variability Of The Colorado River Associated With Karst Springs, Colorado Bend State Park, Central Texas [Abstract], Katie Mitchell, Sherri Dornak, Kevin W. Stafford

Faculty Presentations

No abstract provided.

Challenges And Prospects Of Sustainable Groundwater Management In The Indus Basin, Pakistan, Asad Sarwar Qureshi, Peter G. Mccornick, A. Sarwar, Bharat R. Sharma

Daugherty Water for Food Global Institute: Faculty Publications

In Pakistan, on-demand availability of groundwater has transformed the concept of low and uncertain crop yields into more assured crop production. Increased crop yields have resulted in food security and improved rural livelihoods. However, this growth has also led to problems of overdraft, falling water tables, and degradation of groundwater quality, and yields generally remain well below potential levels. Over the last three decades, Pakistan has tried several direct and indirect management strategies for groundwater management. However the success has been limited. This paper argues that techno-institutional approaches such as introducing water rights, direct or indirect pricing, and permit systems …

The Challenges Of Wastewater Irrigation In Developing Countries, M. Qadir, D. Wichelns, L. Raschid-Sally, Peter G. Mccornick, P. Drechsel, A. Bahri, P. S. Minhas

Daugherty Water for Food Global Institute: Faculty Publications

The volume of wastewater generated by domestic, industrial, and commercial sources has increased with population, urbanization, improved living conditions, and economic development. The productive use of wastewater has also increased, as millions of small-scale farmers in urban and peri-urban areas of developing countries depend on wastewater or wastewater-polluted water sources to irrigate high-value edible crops for urban markets, often as they have no alternative sources of irrigation water. Undesirable constituents in wastewater can harm human health and the environment. Hence, wastewater irrigation is an issue of concern to public agencies responsible for maintaining public health and environmental quality. For diverse …

Comparison Of Carbon Stocks & Importance Values In Correlation With Past Land Use In The Gordon Natural Area, Timothy Hoffer, Steffen Lubbe

Forest Carbon Storage Study Documents

No abstract provided.

Bite Marks Of The Giant Crocodylian Deinosuchus On Late Cretaceous (Campanian) Bones, David R. Schwimmer

Faculty Bibliography

The giant (~10 m) Late Cretaceous eusuchian crocodylians of the genus Deinosuchus are shown to have left large, blunt, sometimes penetrating bite marks on a significant number of sea turtle shells, and on several dinosaur specimens. The morphology of crocodylian bite marks is generally well documented, and the identification of bite traces specifically attributable to Deinosuchus may be made by reference to their size, age, habitat and prey selection. Deinosuchus species, and bite traces referable to the genus, are present on both sides of the Late Cretaceous Interior Seaway, and known only from Campanian deposits in the USA and northern …

Coprolites Of Deinosuchus And Other Crocodylians From The Upper Cretaceous Of Western Georgia, Usa, Samantha D. Harrell, David R. Schwimmer

Faculty Bibliography

Associated with abundant bones, teeth and osteoderms of the giant eusuchian Deinosuchus rugosus are larger concretionary masses of consistent form and composition. It is proposed that these are crocodylian coprolites, and further, based on their size and abundance, that these are coprolites of Deinosuchus. The associated coprolite assemblage also contains additional types that may come from smaller crocodylians, most likely species of the riverine/estuarine genus Borealosuchus, which is represented by bones, osteoderms and teeth in fossil collections from the same site.

An Extraordinary Example Of Photokarren In A Sandstone Cave, Cueva Charles Brewer, Chimantá Plateau, Venezuela: Biogeomorphology On A Small Scale, Joyce Lundberg, Donald A. Mcfarlane, Charles Brewer-Carias

WM Keck Science Faculty Papers

A distinctive suite of small-scale erosional forms that are oriented towards the light occur close to the entrance of Cueva Charles Brewer, a large cave in a sandstone tepui, in SE Venezuela. These are the third example of photokarren ever studied in the world, the other two being from Borneo and Ireland. They are the only photokarren ever described from sandstone, and the only example from a non-carbonate environment. The host rock is a poorly-lithified unit of the Precambrian quartz arenite of the Roraima Supergroup. The forms are all oriented towards the light at 30° regardless of rock surface orientation. …

A Unique Population Of Cave Bears (Carnivora: Ursidae) From The Middle Pleistocene Of Kents Cavern, England, Based On Dental Morphometrics, Donald A. Mcfarlane, Martin Sabol, Joyce Lundberg

WM Keck Science Faculty Papers

The ‘breccia’ stratum from Kents (we follow local tradition in using the form ‘Kents’, without an apostrophe) Cavern, England, has been well known for its rich yield of cave-bear material since excavations began in the mid-19th century. Recent work has established that the bears are of latest MIS 12 or earliest MIS 11 age. A life table based on a collection of 67 molariform teeth is consistent with the use of the cave as a hibernaculum. Univariate and morphological assessment of the teeth shows an unusual range of primitive and more derived characters. Multivariate morphometric analysis of cave-bear teeth from …

A Geographic Information Systems Approach To The 19th Century Excavation Of Brixham Cavern, Devon, England, Donald A. Mcfarlane, Joyce Lundberg, Warren Roberts

WM Keck Science Faculty Papers

The oldest known spatially-explicit archaeological excavation, conducted in Brixham cave, Devon, in 1858, is reconstructed using geographic information systems technology. Two dimensional plots of individual fossil taxa and flint artefacts demonstrate the utility of the technique for elucidating taphonomy and palaeobiology. The cave served as a den for hibernating brown bears, as a den for hyena and cave lion, and as a reliquary for their prey.

Climate In The Southern Sawatch Range And Elk Mountains, Colorado, U.S.A., During The Last Glacial Maximum: Inferences Using A Simple Degree-Day Model, Keith A. Brugger

Geology Publications

Equilibrium-line altitudes (ELAs) were determined from reconstructions of 22 paleoglaciers at their extent during the local last glacial maximum (LGM) using the accumulation-area method. LGM ELAs thus derived ranged from 2980 to 3560 m and follow a statistically significant regional trend of rising ~4.5 m km^-1 to the east. Two approaches using a degree-day model were used to infer LGM climate by finding plausible combinations of temperature and precipitation change that (1) would be required to lower ELAs to their mean LGM values in both the Taylor Park/eastern Elk Mountains region and western Elk Mountains, and (2) provide steady-state …

Fecal Indicator Bacteria Concentrations In Furman Lake And Its Feeder Streams, Philip Hearn, T.J. Melton, Emily Tripp, Victoria Grimm-Oropesa

Furman Lake Restoration Book Gallery

A three page summary by four Furman students describing their research on fecal indicator bacteria in the Furman Lake and streams. The summary contains a map and bar charts.

Differences In Antibiotic Resistance In Fresh-Water Bacteria From Furman Lake And Feeder Streams, Dylan Richards, Clarissa Graham, Laura Snyder

Furman Lake Restoration Book Gallery

A one page summary by three Furman students describing their research on bacteria found in the Furman Lake.

The Effect Of Bioretention Areas On The Heavy Ion Concentration, Ph, And Water Quality Of The Furman University Lake, Adam Williams, Ashley Brown, Matthew Stutz

Furman Lake Restoration Book Gallery

A one page summary by four Furman students describing their research on the effectiveness of the bioretention areas, or rain gardens, created as part of the Lake Restoration Project.

The Distribution Of Macroalgae In Furman Lake, Anthony Guida, Jeff Hennessy, Meredith Yingling, Vanessa Argüello

Furman Lake Restoration Book Gallery

A three page summary by four Furman students describing their research on macroalge in the Furman Lake. The goal is to test whether or not the restoration efforts have significantly changed the algae cover in the lake.

The Effect Of The Lake Restoration Project On Passerine Bird Diversity, Gina Tong, Brittany Martin, Stephanie Field, Whitney Snow, Whitney Millegan, Chris Cowart

Furman Lake Restoration Book Gallery

A three page summary by six Furman students showing their research results on the lake restoration's effects on passerine bird populations.

The Effect Of The Lake Restoration Project On Habitat Use By Waterfowl, Denae Buzzell, Clay Evans, Hannah Shirley, Lin Lin Zhao

Furman Lake Restoration Book Gallery

A two page summary by four Furman students describing their research on waterfowl around the Furman Lake. The summary gives a brief history waterfowl populations and explains the adverse effects of large waterfowl populations on calm bodies of water. The summary concludes with test results showing the success of the lake restoration efforts dealing with waterfowl overpopulation.

Composition And Structure Of The San Andreas Fault Observatory At Depth (Safod) Phase Iii Whole-Rock Core: Implications For Fault Zone Deformation And Fluid-Rock Interactions, Kelly Keighley Bradbury, James P. Evans

Geosciences Presentations

We examine the composition and texture of whole-rock core from ~ 3 km depth in the San Andreas Fault Observatory at Depth (SAFOD) borehole, which provides a unique opportunity to characterize in situ rock properties of the near-fault environment, and how these properties vary in an area where deformation is accommodated by aseismic creep and high-rates of microseismicity. Detailed petrography and microstructural analyses coupled with X-Ray Diffraction and X-ray Fluorescence techniques are used to describe composition, alteration, and textures.

All samples record multiple generations of cataclastic deformation in a complexly deformed and altered sequence of fine-grained sheared rocks. Localized shears …

Observations Of Ozone Production In A Dissipating Tropical Convective Cell During Tc4, Gary A. Morris, A. M. Thompson, K. E. Pickering, S. Chen, E. J. Bucsela, P. A. Kucera

Physics and Astronomy Faculty Publications

From 13 July–9 August 2007, 25 ozonesondes were launched from Las Tablas, Panama as part of the Tropical Composition, Cloud, and Climate Coupling (TC4) mission. On 5 August, a strong convective cell formed in the Gulf of Panama. World Wide Lightning Location Network (WWLLN) data indicated 563 flashes (09:00–17:00 UTC) in the Gulf. NO2 data from the Ozone Monitoring Instrument (OMI) show enhancements, suggesting lightning production of NOx. At 15:05 UTC, an ozonesonde ascended into the southern edge of the now dissipating convective cell as it moved west across the Azuero Peninsula. The balloon oscillated from 2.5–5.1 km five times …

Conversion Of Carbon Dioxide And Hydrogen Into Methane In Bench-Scale Microcosms And Packed Column Reactors, Brian Alexander Congiu

Browse all Theses and Dissertations

Escalating energy demands, rising costs, and increasing awareness of the environmental impacts of current energy sources have created an immediate need for sustainable, alternative energy resources and innovative fuel technologies. It is believed that a potential carbon-neutral fuel source can be generated through the microbial production of methane gas by methanogenic archaea. Carbon dioxide captured from the atmosphere and renewable production of hydrogen can be used to support these microorganisms for the large-scale production of methane. Bench-scale investigations involving 160 mL serum bottle batch experiments and two 11L packed-column reactors were conducted to evaluate the feasibility and efficiency of microbial …

Climatic And Environmental Controls On The Occurrence And Distributions Of Long Chain Alkenones In Lakes Of The Interior United States, Jaime L. Toney, Yongsong Huang, Sherilyn C. Fritz, Paul A. Baker, Eric Grimm, Paul Nyren

Department of Earth and Atmospheric Sciences: Faculty Publications

Long chain alkenones (LCA) are temperature-sensitive lipids with great potential for quantitative reconstruction of past continental climate. We conducted the first survey for alkenone biomarkers from 55 different lakes in the Northern Great Plains and Nebraska Sand Hills of the United States. Among those surveyed, we found 13 lakes that contain LCAs in the surface sediments. The highest concentrations of alkenones in sediments are found in cold (mean annual air temperature ~11 °C versus 17 °C in our warmest sites), brackish to mesosaline (salinity = 8.5–9.7 g/L), and alkaline (pH = 8.4–9.0) lakes with high concentrations of sodium and sulfate. …

One Or Two Species Of The Giant Crocodylian Deinosuchus?, David R. Schwimmer

Faculty Bibliography

No abstract provided.

An Evaluation Of Lead Concentrations In Surface Soils And Sediments Within Lytle Creek Drainage Basin, Harvey Clark Norton

Theses Digitization Project

This paper represents a master's project that is a preliminary surface soil survey of the Lytle Creek sub-Watershed, near Devore, California. The sub-Watershed is a recreational site within the San Bernardino National Forest. This study was undertaken to determine the concentration of lead and lead salts within the soils and sediments within the watershed, and to determine if these products pose a threat to the health of the local environment and human consumers from the watershed. Possible sources of lead contamination include natural background geology, contamination of historical use of gasoline with lead additives, and the presence of outdoor shooting …

Compositions Of Subsurface Ices At The Mars Phoenix Landing Site, Selby Cull, Raymond E. Arvidson, Michael T. Mellon, Philip Skemer, Amy Shaw, Richard V. Morris

Geology Faculty Research and Scholarship

NASA's Phoenix Lander uncovered two types of ice at its 2008 landing site on the northern plains of Mars: a brighter, slab-like ice that broke during Robotic Arm operations; and a darker icy deposit. Spectra from the Phoenix Surface Stereo Imager (SSI) are used to demonstrate that the brighter material consists of nearly pure water ice, which probably formed by migration and freezing of liquid water. The darker icy material consists of similar to 30 +/- 20 wt% ice, with the remainder composed of fine-grained soil, indicating that it probably formed as pore ice. These two types of ice represent …