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Evaluation Of The Carbon Budgets In The Forested And Agricultural Soils Of The Semi-Arid Mogollon-Datil Highlands And Rio Grande Basin, Ryan Reeves^, Lixin Jin* 2011 Department of Geological Sciences, University of Texas at El Paso

Evaluation Of The Carbon Budgets In The Forested And Agricultural Soils Of The Semi-Arid Mogollon-Datil Highlands And Rio Grande Basin, Ryan Reeves^, Lixin Jin*

COURI Symposium Abstracts, Summer 2011

No abstract provided.


Taxonomy And Geochemistry Of The Globigerinoides Ruber-Elongatus Plexus, With Paleontological Implications, Elizabeth Ann Brown 2011 University of South Florida

Taxonomy And Geochemistry Of The Globigerinoides Ruber-Elongatus Plexus, With Paleontological Implications, Elizabeth Ann Brown

USF Tampa Graduate Theses and Dissertations

The reliability of foraminifera as stratigraphic index fossils, and as isotopic proxies of marine environments, is based on the assumption that the fossil concepts represent uniform species, responding consistently to their ambient environments. Understanding sources of uncertainty is, therefore, critical. In this dissertation, I explore a potential bias in the application of planktonic foraminifera utilized extensively for Cenozoic paleo-reconstruction and, to a lesser extent, biostratigraphy: the Globigerinoides ruber-elongatus plexus (‘plexus’ meaning a complex network of interconnected members). Taxonomic revisions since 1826 have resulted in the merging of multiple Globigerinoides species names under one general designation (“Globigerinoides ruber”), the implications of …


Stratigraphic Analysis And Regional Correlation Of Isolated, Top-Truncated Shallow Marine Sandstone Bodies Within The Upper Cretaceous Frontier Formation, Bighorn And Washakie Counties, Wyoming, Andrew J. Hutsky 2011 University of Nebraska-Lincoln

Stratigraphic Analysis And Regional Correlation Of Isolated, Top-Truncated Shallow Marine Sandstone Bodies Within The Upper Cretaceous Frontier Formation, Bighorn And Washakie Counties, Wyoming, Andrew J. Hutsky

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

A detailed sedimentologic and stratigraphic analysis facilitated interpretations of depositional environment, sequence stratigraphy, and sandstone body geometry for isolated, top-truncated, shallow marine sandstone bodies of the Upper Cretaceous (Cenomanian-Turonian) Frontier Formation, northeast Bighorn Basin, Wyoming. The Frontier Formation interval is ~160 meters thick and was deposited as a complex clastic wedge that prograded into Cretaceous Western Interior Seaway (KWIS). The vertical interval comprises several incomplete coarsening-upward cycles, composed of basal offshore marine and prodeltaic shales progressively overlain by proximal shallow marine/fluvial facies that are capped by pebble lags. Sedimentary structures, vertical stacking patterns, and lateral variability within these cycles record …


Techniques To Promote Garry Oak Seedling Growth And Survival In Areas With High Levels Of Herbivory And Competition, David R. Clements, Seth Luginbill, David A. Jordan, Randall Dragt 2011 Trinity Western University

Techniques To Promote Garry Oak Seedling Growth And Survival In Areas With High Levels Of Herbivory And Competition, David R. Clements, Seth Luginbill, David A. Jordan, Randall Dragt

University Faculty Publications and Creative Works

Though regeneration of Garry oak (Quercus garryana) seedlings within Garry oak ecosystems is important to maintain this threatened habitat, seedling regeneration is often poor. Two independent studies were initiated in the early 2000s to examine questions surrounding Garry oak recruitment: one at the Crow's Nest Ecological Research Area (CNERA) on Salt Spring Island, BC, and another at the Pacific Rim Institute for Environmental Stewardship (PRI) on Whidbey Island, WA. In both areas, Garry oak seedlings were caged and monitored for growth and relative health. Over 8 years at CNERA, growth of caged plants outpaced growth of controls, which was indicative …


Mammalian Fauna From The Fullerton Gravel Pit (Ogallala Group, Late Miocene), Morton County, Kansas, Michael Anthony Calvello 2011 Fort Hays State University

Mammalian Fauna From The Fullerton Gravel Pit (Ogallala Group, Late Miocene), Morton County, Kansas, Michael Anthony Calvello

Master's Theses or Doctor of Nursing Practice

The Fullerton Gravel Pit, Morton County, Kansas is one of many sites in western Kansas at which the Ogallala Group crops out. The Ogallala Group was deposited primarily by streams flowing from the Rocky Mountains. Evidence of water transport is observable at the Fullerton Gravel Pit through the presence of allochthonous clasts, cross-bedding, pebble alignment, and fossil breakage and subsequent rounding. Fluvial mechanisms also played an important role in the distribution of fossil material. When the fossils from the Fullerton Gravel Pit are placed in Voorhies Groups, it appears that a majority of them were removed from suspension gradually and …


New Stable Isotope Record Of Paleoecological Change In The Late Neogene Of The Western Great Plains From Enamel In Large Mammals, Zachary Kita 2011 University of Nebraska-Lincoln

New Stable Isotope Record Of Paleoecological Change In The Late Neogene Of The Western Great Plains From Enamel In Large Mammals, Zachary Kita

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

An expansion of C4 grasslands occurred between 6 and 8 million years ago in the Great Plains of North America, as evidenced by a marked shift to more 13C-enriched carbon isotope compositions from large fossil mammal tooth enamel and paleosol carbonates. Prior to this expansion, habitats were comprised of exclusively C3 vegetation. To explore this problem I present a compilation of bulk stable carbon (δ13C) and oxygen (δ18O) isotope values from a variety of large mammals from 6 localities that span from the late Clarendonian to the late Blancan in Nebraska. As expected, …


Identifying Changes In Climatic Trends And The Fingerprints Of Landuse And Landcover Changes In The High Plains Of The Usa, Denis Mutiibwa 2011 University of Nebraska-Lincoln

Identifying Changes In Climatic Trends And The Fingerprints Of Landuse And Landcover Changes In The High Plains Of The Usa, Denis Mutiibwa

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Human activities such as conversion of natural ecosystem to croplands and urban-centers, deforestation and afforestation impact biophysical properties of land surface such as albedo, energy balance, and surface roughness. Alterations in these properties affect the heat and moisture exchanges between the land surface and atmospheric boundary layer. The objectives of this research were; (i) to quantitatively identify the High plains’ regional climate change in temperatures over the period 1895 to 2006, (ii) detect the signatures of anthropogenic forcing of LULC changes on the regional climate change of the High Plains, and (iii) examine the trends in evolving regional latent heat …


Polygonal Sandcracks: Unique Sedimentary Desiccation Structures In Bahamian Ooid Grainstone, Bosiljka Glumac, H. Allen Curran, Sarah A. Motti, Madeline M. Weigner, Sarah Pruss 2011 Smith College

Polygonal Sandcracks: Unique Sedimentary Desiccation Structures In Bahamian Ooid Grainstone, Bosiljka Glumac, H. Allen Curran, Sarah A. Motti, Madeline M. Weigner, Sarah Pruss

Geosciences: Faculty Publications

Sandcracks, which are ubiquitous in Holocene eolian and beach backshore carbonate grainstone on Alligator Point, Cat Island, Bahamas, resemble polygonal mudcracks, but formed in ooid sand without muddy matrix. In experiments on Cat Island beach sand, sediment surfaces cracked polygonally in the absence of mud or biofi lms while drying at room temperature due to contraction generated by capillary effects related to surface tension attraction of interstitial water. Gravitational collapse of irregular open pores and repacking of sand grains due to loss of cohesion between particles caused by evaporation of water enhance the cracking process and appearance of polygons by …


Full Conference Program With Abstracts, Jason S. Polk, Leslie A. North 2011 Western Kentucky University Hoffman Institute

Full Conference Program With Abstracts, Jason S. Polk, Leslie A. North

International 2011 Conference on Karst Hydrogeology and Ecosystems

No abstract provided.


From Sink To Resurgence: The Buffering Capacity Of A Cave System In The Tongass National Forest, Usa, Chris Groves, Melissa Hendrikson 2011 Western Kentucky University

From Sink To Resurgence: The Buffering Capacity Of A Cave System In The Tongass National Forest, Usa, Chris Groves, Melissa Hendrikson

Earth, Environmental, and Atmospheric Sciences Faculty Publications

The Tongass National Forest of Southeast Alaska, USA, provides a unique environment for monitoring the impact of the cave system on water quality and biological productivity. The accretionary terrane setting of the area has developed into a complex and heterogeneous geologic landscape which includes numerous blocks of limestone with intense karstification. During the Wisconsian glaciation, there were areas of compacted glacial sediments and silts deposited over the bedrock. Muskeg peatlands developed over these poorly drained areas. The dominant plants of the muskeg ecosystem are Sphagnum mosses, whose decomposition leads to highly acidic waters with pH as low as 2.4. These …


Landslide Susceptibility In Tryon State Park, Oregon, Tracy E. Handrich 2011 Portland State University

Landslide Susceptibility In Tryon State Park, Oregon, Tracy E. Handrich

Anthós

LIDAR and topographic data were used to identify areas of high landslide susceptibility. An arctangent equation was used to calculate slope angle, design criteria of susceptibility and designate zones of high, moderate, and low risk.


Secretive Marsh Bird Species Co-Occurrences And Habitat Associations Across The Midwest, Usa, Jason R. Bolenbaugh, Sarah E. Lehnen, David G. Krementz 2011 University of Arkansas, Fayetteville

Secretive Marsh Bird Species Co-Occurrences And Habitat Associations Across The Midwest, Usa, Jason R. Bolenbaugh, Sarah E. Lehnen, David G. Krementz

United States Geological Survey: Staff Publications

Because secretive marsh birds are difficult to detect, population status and habitat use for these birds are not well known. We conducted repeated surveys for secretive marsh birds across 264 sites in the Upper Mississippi River and Great Lakes Joint Venture region to estimate abundance, occupancy, and detection probabilities during the 2008 and 2009 breeding seasons. We identified species groups based on observed species co-occurrences. Two species, least bittern Ixobrychus exilis and American bittern Botaurus lentiginosus, co-occurred with other species less often than expected by chance, and two species groups, rails (Virginia rail Rallus limicola and sora Porzana carolina) and …


Crustal Structure And Evolution Beneath The Colorado Plateau And The Southern Basin And Range Province: Results From Receiver Function And Gravity Studies, Lamuail Bashir, Stephen S. Gao, Kelly H. Liu, Kevin Lee Mickus 2011 Missouri University of Science and Technology

Crustal Structure And Evolution Beneath The Colorado Plateau And The Southern Basin And Range Province: Results From Receiver Function And Gravity Studies, Lamuail Bashir, Stephen S. Gao, Kelly H. Liu, Kevin Lee Mickus

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Over the past several decades, contrasting models have been proposed for the physical and chemical processes responsible for the uplift and long-term stability of the Colorado Plateau (CP) and crustal thinning beneath the Basin and Range Province (BRP) in the southwestern United States. Here we provide new constraints on the models by modeling gravity anomalies and by systematically analyzing over 15,500 P-to-S receiver functions recorded at 72 USArray and other broadband seismic stations on the southwestern CP and the southern BRP. Our results reveal that the BRP is characterized by a thin crust (28.2 ± 0.5 km), a mean V …


The Impact Of Modern Weathering On The Geochemistry Of A Marine Permo-Triassic Boundary Section, Jeremy Christopher Williams 2011 University of Massachusetts Boston

The Impact Of Modern Weathering On The Geochemistry Of A Marine Permo-Triassic Boundary Section, Jeremy Christopher Williams

Graduate Masters Theses

The Permian-Triassic Boundary (PTB) marks the end-Permian extinction, the greatest mass extinction recorded in Earth's history. The Attargoo PTB section located in Spiti Valley, Himachal Pradesh, India was situated along the north continental margin of Gondwana-land in the Neo-Tethys Ocean during the end-Permian extinction. In Spiti Valley, PTB sections such as Attargoo are exposed by a thin (~ 2cm) ferruginous layer separating the Permian black shale from Triassic Limestone. Studies that have presented geochemical data to support a theory of the end-Permian extinction lack any interpretation of post-depositional effects on Spiti Valley PTB sections. In order to accurately present a …


Taxonomic Composition, Paleoecology And Biostratigraphy Of Late Cretaceous Diatoms From Devon Island, Nunavut, Canadian High Arctic, Jakub Witkowski, David M. Harwood, Karen Chin 2011 University of Warsaw, Poland

Taxonomic Composition, Paleoecology And Biostratigraphy Of Late Cretaceous Diatoms From Devon Island, Nunavut, Canadian High Arctic, Jakub Witkowski, David M. Harwood, Karen Chin

Department of Earth and Atmospheric Sciences: Faculty Publications

Upper Cretaceous sediments of the Kanguk Formation exposed in Eidsbotn and Viks Fiord grabens on Devon Island, Nunavut, Canadian High Arctic, yielded 91 fossil marine diatom species and varieties (including indeterminate taxa), representing 41 genera. Excellent preservation of the assemblages was aided by shallow burial, protection in down­faulted linear grabens, and the presence of abundant volcanic material. Planktonic species and resting spores com­prise nearly 70% of the diatom assemblage, and provided abundant food resources for the Late Cretaceous Arctic eco­system. Deposition of the approximately 225 m-thick stratigraphic sequence was predominantly in a shallow marine neritic setting, with an upward progression …


Dendrochronological Dating Of The Johnson House, Perry County, Ohio, 2011 The College of Wooster

Dendrochronological Dating Of The Johnson House, Perry County, Ohio

Historic Structures

Dating historical structures in Perry County, Ohio. The Historical Structures collection consists of reports that are the resoult of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: Theisen, Jon; Wiles, Greg


Dendrochronological Dating Of Perry County District Library, Somerset, Ohio, 2011 The College of Wooster

Dendrochronological Dating Of Perry County District Library, Somerset, Ohio

Historic Structures

Dating historical structures in Somerset, Ohio 2011. The Historical Structures collection consists of reports that are the resoult of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: Mudd, Anna; Theisen, Jon; Wiles, Greg


Dendrochronological Dating Of The Linnabary House, Worthington, Ohio, 2011 The College of Wooster

Dendrochronological Dating Of The Linnabary House, Worthington, Ohio

Historic Structures

Dating historical structures in Worthington, Ohio 2011. The Historical Structures collection consists of reports that are the result of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: Theisen, Jon; Wiles, Greg


Dendrochronological Dating Of The Old Rectory, Worthington, Ohio, 2011 The College of Wooster

Dendrochronological Dating Of The Old Rectory, Worthington, Ohio

Historic Structures

Dating historical structures in Worthington, Ohio. Dating historical structures in Worthington, Ohio. The Historical Structures collection consists of reports that are the result of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: Theisen, Jon; Wiles, Greg


The Formation History Of Layered Chondrules In Acfer-139 (Cr2), Matt Downen 2011 Western Kentucky University

The Formation History Of Layered Chondrules In Acfer-139 (Cr2), Matt Downen

Mahurin Honors College Capstone Experience/Thesis Projects

Chondrules are spherical grains made of silicates and metal that represent some of the oldest materials our solar system. Acfer-139 (CR) is a carbonaceous chondrite with large multilayered chondrules. The multilayered chondrules are composed of a silicate core surrounded by alternating layers of silicates and metals. Serial sectioning was used to analyze the sample in three dimensions. EMPA and LA-ICP-MS were used to create elemental maps of Acfer-139 (CR2) and determine the geochemistry of different layers in each thick section cut. XRCMT was used to construct a 3-D model of a large multilayered chondrule named Ch-1 with concentric layers of …


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