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Dynamics Of Nitrate, Phosphorus, And Suspended Sediment Transport In Two Agricultural Streams In Central Illinois, Luke W. Lampo 2017 Illinois State University

Dynamics Of Nitrate, Phosphorus, And Suspended Sediment Transport In Two Agricultural Streams In Central Illinois, Luke W. Lampo

Theses and Dissertations

Nutrients such as nitrate and phosphorus are necessary for life, but excessive amounts can be detrimental. Large amounts of nutrients entering bodies of water can lead to hypoxic zones such as the one in the Gulf of Mexico. Nutrients are also problematic in drinking water reservoirs, as high concentrations of nitrate in drinking water can cause health conditions such as blue baby syndrome and high phosphorus concentrations can lead to algal blooms. Suspended sediment leads to reservoir sedimentation, habitat degradation, and is able to transport particulate nutrients. High nutrient and sediment concentrations are a recurring problem in the drinking water ...


A Multi-Proxy Stalagmite Reconstruction Of The Climate Of Southwestern North America From The Middle To Late Holocene, Christine Allen 2017 University of New Mexico

A Multi-Proxy Stalagmite Reconstruction Of The Climate Of Southwestern North America From The Middle To Late Holocene, Christine Allen

Earth and Planetary Sciences ETDs

The seasonal balance of moisture has a significant effect on natural ecosystems and culture in southwestern North America (SWNA), and it thus is necessary to understand the cause of this moisture variability in order to better predict the scope of potential future changes. Studies of modern SWNA climate indicate that most of the annual moisture at this site comes from monsoonal summer precipitation and a lesser amount of Pacific winter moisture. The climate of the Holocene is of particular interest for constraining natural variability of interglacial climates prior to any anthropogenic influence. An overall transition to a wetter Late Holocene ...


Results Of Test-Hole Drilling For Observation Well Planning In The Upper Loup Natural Resources District, Fall 2016, Douglas Hallum, Sue Olafsen Lackey 2017 University of Nebraska-Lincoln

Results Of Test-Hole Drilling For Observation Well Planning In The Upper Loup Natural Resources District, Fall 2016, Douglas Hallum, Sue Olafsen Lackey

Conservation and Survey Division

The High Plains Aquifer underlies much of Nebraska (Figure 1). It is the primary source of groundwater within the Upper Loup Natural Resources District (ULNRD) of central Nebraska (Figure 2). Water derived from the aquifer is an important natural resource for the area and supplies water for recreation, wildlife and agriculture, as well as domestic, municipal, and industrial uses. A general lack of water level observations in the region (Figure 3), recently developed groundwater irrigated acres along the upper Calamus River (Figure 4), falling spring water levels measured in existing irrigation wells (Figure 5), and a stable to falling stream ...


Evaporite Karst In Italy: A Review, Jo De Waele, Leonardo Piccini, Andrea Columbu, Giuliana Madonia, Marco Vattano, Chiara Calligaris, Ilenia D’Angeli, Mario Parise, Mauro Chiesi, Michele Sivelli, Bartolomeo Vigna, Luca Zini, Veronica Chiarini, Francesco Sauro, Russell Drysdale, Paolo Forti 2017 University of Bologna

Evaporite Karst In Italy: A Review, Jo De Waele, Leonardo Piccini, Andrea Columbu, Giuliana Madonia, Marco Vattano, Chiara Calligaris, Ilenia D’Angeli, Mario Parise, Mauro Chiesi, Michele Sivelli, Bartolomeo Vigna, Luca Zini, Veronica Chiarini, Francesco Sauro, Russell Drysdale, Paolo Forti

International Journal of Speleology

Although outcropping rarely in Italy, evaporite (gypsum and anhydrite) karst has been described in detail since the early 20th century. Gypsum caves are now known from almost all Italian regions, but are mainly localised along the northern border of the Apennine chain (Emilia Romagna and Marche), Calabria, and Sicily, where the major outcrops occur. Recently, important caves have also been discovered in the underground gypsum mines in Piedmont. During the late 80s and 90s several multidisciplinary studies were carried out in many gypsum areas, resulting in a comprehensive overview, promoting further research in these special karst regions. More recent ...


Oysters And Mammoths: Fossils In Central Texas–Texas Academy Of Science 2017, Chris Barker, R. LaRell Nielson 2017 Stephen F Austin State University

Oysters And Mammoths: Fossils In Central Texas–Texas Academy Of Science 2017, Chris Barker, R. Larell Nielson

Faculty Publications

Texas Academy of Science, 2017 Field Trip

This year's Texas Academy of Science Geology Field Trip takes you to two very different fossil sites in central Texas. Stop 1 is along a quiet road in the Hill Country where you can collect abundant invertebrate fossils from the Lower Cretaceous Comanche Peak Limestone and Walnut Clay. The second stop of the trip is at one of the newest units of America's park service: the Waco Mammoth National Monument. At this site you will see a spectacular fossil discovery that is now one of the main mammoth sites in North ...


The Dynamic Geomorphic Setting Of The Late Pleistocene Hartley Mammoth Site: Burial And Skeletal Preservation In A Slump-Block Depression Near Abiquiu, New Mexico, Jennifer K. Muus 2017 University of New Mexico

The Dynamic Geomorphic Setting Of The Late Pleistocene Hartley Mammoth Site: Burial And Skeletal Preservation In A Slump-Block Depression Near Abiquiu, New Mexico, Jennifer K. Muus

Earth and Planetary Sciences ETDs

Near Abiquiu in northern New Mexico, the skeletal remains of two mammoths were discovered in the summer of 2014 in the near-surface deposits of a very small alluvial channel. The channel occupies a depression on the backtilted top of a Toreva slump block, a highly unusual setting for a mammoth burial. Geomorphological investigation of the site has provided insight into processes leading to burial and preservation of the remains, as well as local environmental change. Field mapping of sediment sources and LiDAR scans of the contributing slope basin and slump bench provided a map of geomorphic features and surficial geologic ...


Stream Terrace Genesis Along Bunte Creek In The Elkhorn Plain, Ca, Madi Allgaier, Shelley Anderson, Duncan Lord 2017 California Polytechnic State University, San Luis Obispo

Stream Terrace Genesis Along Bunte Creek In The Elkhorn Plain, Ca, Madi Allgaier, Shelley Anderson, Duncan Lord

Natural Resources Management and Environmental Sciences

There are several factors influencing terrace genesis and terrace types in Bunte Creek. Strath terraces exist at upper Bunte Creek, whereas thick fill terraces exist at lower Bunte Creek. Analysis of these terraces leads to insight on what specific factors lead to their formation. Terraces were mapped along the extent of Bunte Creek. Sediment data and terrace-height data were collected for in order to make a complete analysis of the terraces. Tectonic uplift led to incision and strath terrace genesis at upper Bunte Creek. Climatic forcing and base-level rise caused alluvial aggradation behind a shutter ridge that intersects lower Bunte ...


The Influence Of Föhn Winds On Glacial Lake Washburn And Palaeotemperatures In The Mcmurdo Dry Valleys, Antarctica, During The Last Glacial Maximum, Maciej Obryk, Peter Doran, Ed Waddington, Chris McKay 2017 Portland State University

The Influence Of Föhn Winds On Glacial Lake Washburn And Palaeotemperatures In The Mcmurdo Dry Valleys, Antarctica, During The Last Glacial Maximum, Maciej Obryk, Peter Doran, Ed Waddington, Chris Mckay

Geology Faculty Publications and Presentations

Large glacial lakes, including Glacial Lake Washburn, were present in the McMurdo Dry Valleys, Antarctica, during the Last Glacial Maximum (LGM) despite a colder and drier climate. To address the mechanism capable of generating enough meltwater to sustain these large lakes, a conceptual model was developed based on the warming potential of infrequent contemporary föhn winds. The model suggests that föhn winds were capable of generating enough meltwater to sustain large glacial lakes during the LGM by increasing degree days above freezing (DDAF) and prolonging the melt season. A present-day relationship between infrequent summer föhn winds and DDAF was established ...


Ground-Rupturing Earthquakes On The Northern Big Bend Of The San Andreas Fault, California, 800a.D. To Present, Katherine Scharer, Ray J. Weldon II, Glenn Biasi, Ashley Strieg, Thomas Fumal 2017 U.S. Geological Survey

Ground-Rupturing Earthquakes On The Northern Big Bend Of The San Andreas Fault, California, 800a.D. To Present, Katherine Scharer, Ray J. Weldon Ii, Glenn Biasi, Ashley Strieg, Thomas Fumal

Geology Faculty Publications and Presentations

Paleoseismic data on the timing of ground-rupturing earthquakes constrain the recurrence behavior of active faults and can provide insight on the rupture history of a fault if earthquakes dated at neighboring sites overlap in age and are considered correlative. This study presents the evidence and ages for 11 earthquakes that occurred along the Big Bend section of the southern San Andreas Fault at the Frazier Mountain paleoseismic site. The most recent earthquake to rupture the site was the Mw7.7–7.9 Fort Tejon earthquake of 1857. We use over 30 trench excavations to document the structural and sedimentological evolution ...


Young Earth Flood Geology In The Grand Canyon, John H. Whitmore 2017 Cedarville University

Young Earth Flood Geology In The Grand Canyon, John H. Whitmore

Science and Mathematics Faculty Publications

No abstract provided.


Mechanical Models Favor A Ramp Geometry For The Ventura-Pitas Point Fault, California, Scott T. Marshall, Gareth J. Funning, Hannah E. Kreuger, Susan E. Owen, John P. Loveless 2017 Appalachian State University

Mechanical Models Favor A Ramp Geometry For The Ventura-Pitas Point Fault, California, Scott T. Marshall, Gareth J. Funning, Hannah E. Kreuger, Susan E. Owen, John P. Loveless

Geosciences: Faculty Publications

Recent investigations have provided new and significantly revised constraints on the subsurface structure of the Ventura-Pitas Point fault system in southern California; however, few data directly constrain fault surfaces below ~6 km depth. Here, we use geometrically complex three-dimensional mechanical models driven by current geodetic strain rates to test two proposed subsurface models of the fault system. We find that the model that incorporates a ramp geometry for the Ventura-Pitas Point fault better reproduces both the regional long term geologic slip rate data and interseismic GPS observations of uplift in the Santa Ynez Mountains. The model-calculated average reverse slip rate ...


Cu-Pd Mineralization And Exploration Geochemistry Of The Eastern Gabbro, Coldwell Alkaline Complex, On, Canada, Yonghua Cao 2017 The University of Western Ontario

Cu-Pd Mineralization And Exploration Geochemistry Of The Eastern Gabbro, Coldwell Alkaline Complex, On, Canada, Yonghua Cao

Electronic Thesis and Dissertation Repository

The Eastern Gabbro forms the northern and eastern margin of the Coldwell Alkaline Complex. It contains three magma series: the barren meta-basalt, the Layered Series, and the Marathon Series which hosts all known PGE mineralization. The Marathon Series can be distinguished from other Series using the combination of portable X-ray fluorescence (pXRF) and benchtop scanning electron microscope (bSEM). Whole-rock Ba, Mg# (molar Mg/(Mg+Fe)*100), Zr and V/Ti values acquired from pXRF, and Mg#s of olivine and clinopyroxene, and anorthite content (molar Ca/(Ca+Na)*100) of plagioclase acquired from bSEM-EDS are key parameters. The Layered Series ...


Murray Energy Corporation V. Mccarthy, Sarah M. Danno 2017 University of Montana School of Law

Murray Energy Corporation V. Mccarthy, Sarah M. Danno

Public Land and Resources Law Review

Holding that the widespread effects of environmental regulation on the coal industry constituted sufficient importance, the Northern District of West Virginia ordered the Environmental Protection Agency to conduct analysis on employment loss and plant reduction resulting from regulatory effects. In admonishing the EPA’s inaction, the court ruled that the Agency had a non-discretionary duty to evaluate employment and plant reduction. Furthermore, the court held that the EPA’s attempt to put forth general reports in place of required evaluations was an invalid attempt to circumvent its statutory duty.


Super-Interseismic Periods: Redefining Earthquake Recurrence, John P. Loveless 2017 Smith College

Super-Interseismic Periods: Redefining Earthquake Recurrence, John P. Loveless

Geosciences: Faculty Publications

Precise geodetic measurements made over broad swaths of tectonically active regions record patterns of interseismic strain accumulation, providing key insights into the locus and timing of pending earthquakes. Recent studies of geodetic position time series, including that of Melnick et al. (2017), illustrate temporal variation in the pattern of interseismic deformation. These authors propose that the 2010 Mw = 8.8 Maule, Chile, earthquake enhanced coupling on the Andean subduction zone adjacent to the rupture, including on the portion of the megathrust that broke 5 years later in the Mw = 8.3 Illapel event.


So, You Want To 3d Print A Landscape? An Outline Of Some Methods, Dylan J. McKevitt, Thomas L. Rice, Emily Jackson, Victoria Couser 2017 Cedarville University

So, You Want To 3d Print A Landscape? An Outline Of Some Methods, Dylan J. Mckevitt, Thomas L. Rice, Emily Jackson, Victoria Couser

Alumni Book Gallery

No abstract provided.


The Tuscaloosa Marine Shale: Geologic History, Depositional Analysis, And Exploration Potential, Jessica D. Pair 2017 Stephen F Austin State University

The Tuscaloosa Marine Shale: Geologic History, Depositional Analysis, And Exploration Potential, Jessica D. Pair

Electronic Theses and Dissertations

The Tuscaloosa Marine Shale (TMS) was deposited across southern Louisiana and Mississippi during the Upper Cretaceous. The study focuses on a core region containing vast deposits of Cretaceous-aged sediments that have economic importance for oil and gas exploration. This region has been conventionally drilled for decades, focusing on the recovery of the Cretaceous hydrocarbons. Explorers within this region had traditionally targeted the massive sand units of the Lower and Upper Tuscaloosa Group while neglecting the middle Tuscaloosa Marine Shale unit. With the onset of unconventional drilling technology, new explorers to the region have begun to delineate the Tuscaloosa Marine Shale ...


Secondary Minerals From Salt Caves In The Atacama Desert (Chile): A Hyperarid And Hypersaline Environment With Potential Analogies To The Martian Subsurface, Jo De Waele, Cristina Carbone, Laura Sanna, Marco Vattano, Ermanno Galli, Francesco Sauro, Paolo Forti 2017 University of Bologna

Secondary Minerals From Salt Caves In The Atacama Desert (Chile): A Hyperarid And Hypersaline Environment With Potential Analogies To The Martian Subsurface, Jo De Waele, Cristina Carbone, Laura Sanna, Marco Vattano, Ermanno Galli, Francesco Sauro, Paolo Forti

International Journal of Speleology

Over the past 15 years several expeditions by French, American and especially Italian cavers have unveiled over 50 caves in the Cordillera de la Sal (Atacama Desert, Northern Chile). Many of these caves contain a variety of speleothems and minerals, some of which have rarely been observed within karst systems. Most of the secondary deposits in these caves are composed of halite, but also other halide, carbonate, sulphate, nitrate, phosphate, and silicate minerals have been found. Among the sixteen cave mineral species recognized, atacamite, darapskite, blödite, leonite, anhydrite, and especially antarcticite are worth mentioning. In one of the samples an ...


Toxicity Of Fluorescent Tracers And Their Degradation Byproducts, Philippe Gombert, Hugues Biaudet, René de Sèze, Pascal Pandard, Jean Carré 2017 INERIS

Toxicity Of Fluorescent Tracers And Their Degradation Byproducts, Philippe Gombert, Hugues Biaudet, René De Sèze, Pascal Pandard, Jean Carré

International Journal of Speleology

Tracer tests are frequently used to delineate catchment area of water supply springs in karstic zones. In the karstic chalk of Normandy, the main tracers used are fluorescent: uranine, sulforhodamine B, naphtionate, and Tinopal®. In this area, a statistical analysis shows that less than half of the injected tracers joins the monitored restitution points and enters the drinking water system where they undergo chlorination. Most of the injected tracers is absorbed in the rock matrix or is thrown out of the aquifer via karstic springs: then it can join superficial waters where it is degraded due to the sun and ...


Review Of A Chorus Of Cranes: The Cranes Of North America And The World By Paul A. Johnsgard, Aaron T. Pearse 2017 U.S. Geological Survey

Review Of A Chorus Of Cranes: The Cranes Of North America And The World By Paul A. Johnsgard, Aaron T. Pearse

USGS Staff -- Published Research

Cranes (Gruidae) are widely distributed throughout the world, have lived on Earth for several million years, and currently reside on five continents. Archaeological evidence and historical references suggest that humans have interacted with and been captivated by cranes for many thousands of years (e.g., Leslie 1988, Muellner 1990). A glimpse of our reverence for these birds can be found in A Chorus of Cranes by Paul A. Johnsgard, with photographs by Thomas D. Mangelsen. Many species of cranes are currently identified as threatened or endangered, and their future will likely rest in the hands of humans; this book presents ...


Mercury Increases In Lake Tanganyika Since ~1850, Troy A. Bole 2017 The University of Akron

Mercury Increases In Lake Tanganyika Since ~1850, Troy A. Bole

Honors Research Projects

A series of three sediment cores were collected in Lake Tanganyika, Africa, and were analyzed for mercury concentrations. For all three cores, a decrease in mercury (Hg) levels was observed from the 1600’s (appx. 20 ng/g) until concentrations reached a minimum during the mid-1800’s (appx. 10 ng/g). The mid-1800’s marked a change from decreasing mercury levels to an increase over the following century. The core tops (circa 2006) have concentrations greater than 70 ng/g. The onset of the rise in mercury concentrations coincides with the beginning of the Industrial Revolution in the mid to ...


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