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29,939 full-text articles. Page 1186 of 1248.

A Satellite Data Driven Biophysical Modeling Approach For Estimating Northern Peatland And Tundra Co2 And Ch4 Fluxes, J. D. Watts, John S. Kimball, F. J. W. Parmentier, T. Sachs, J. Rinne, D. Zona, W. Oechel, T. Tagesson, M. Jackowicz-Korczynski, M. Aurela 2014 University of Montana - Missoula

A Satellite Data Driven Biophysical Modeling Approach For Estimating Northern Peatland And Tundra Co2 And Ch4 Fluxes, J. D. Watts, John S. Kimball, F. J. W. Parmentier, T. Sachs, J. Rinne, D. Zona, W. Oechel, T. Tagesson, M. Jackowicz-Korczynski, M. Aurela

Biological Sciences Faculty Publications

The northern terrestrial net ecosystem carbon balance (NECB) is contingent on inputs from vegetation gross primary productivity (GPP) to offset the ecosystem respiration (Reco) of carbon dioxide (CO2) and methane (CH4) emissions, but an effective framework to monitor the regional Arctic NECB is lacking. We modified a terrestrial carbon flux (TCF) model developed for satellite remote sensing applications to evaluate wetland CO2 and CH4 fluxes over pan-Arctic eddy covariance (EC) flux tower sites. The TCF model estimates GPP, CO2 and CH4 emissions using in situ or remote sensing and reanalysis-based climate data as inputs. …


Seismic Anisotropy And Subduction-Induced Mantle Fabrics Beneath The Arabian And Nubian Plates Adjacent To The Red Sea, Ahmed A. Elsheikh, Stephen S. Gao, Kelly H. Liu, Abdelnasser A. Mohamed, Youqiang Yu, Raafat E. Fat-Helbary 2014 Missouri University of Science and Technology

Seismic Anisotropy And Subduction-Induced Mantle Fabrics Beneath The Arabian And Nubian Plates Adjacent To The Red Sea, Ahmed A. Elsheikh, Stephen S. Gao, Kelly H. Liu, Abdelnasser A. Mohamed, Youqiang Yu, Raafat E. Fat-Helbary

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

For most continental areas, the mechanisms leading to mantle fabrics responsible for the observed anisotropy remain ambiguous, partially due to the lack of sufficient spatial coverage of reliable seismological observations. Here we report the first joint analysis of shear-wave splitting measurements obtained at stations on the Arabian and Nubian Plates adjacent to the Red Sea. More than 1100 pairs of high-quality splitting parameters show dominantly N-S fast orientations at all 47 stations and larger-than-normal splitting times beneath the Afro-Arabian Dome (AAD). The uniformly N-S fast orientations and large splitting times up to 1.5 s are inconsistent with significant contributions from …


Geology, The Marcellus Shale, Experts, And Dispute Resolution, Itzchak E. Kornfeld 2014 Hebrew University of Jerusalem

Geology, The Marcellus Shale, Experts, And Dispute Resolution, Itzchak E. Kornfeld

West Virginia Law Review

No abstract provided.


The Geologic Framework Of Acoma Pueblo And Its Cultural Context: A Western & Native Perspective, Darryl Reano 2014 Purdue University

The Geologic Framework Of Acoma Pueblo And Its Cultural Context: A Western & Native Perspective, Darryl Reano

Open Access Theses

The sequence of sedimentary rocks at Acoma Pueblo, New Mexico, are important both in terms of their cultural significance for the Native people of Acoma Pueblo and the insight they provide into the long term geologic history of the Colorado Plateau. In this thesis we present the first stratigraphic and provenance analysis of the Mesozoic strata at Acoma Pueblo, New Mexico, based on field observations and detrital zircon U-Pb geochronology. Acoma Pueblo was located in the distal part (i.e. backbulge) of a foreland basin system during most of the Mesozoic. Acoma Pueblo has not been included in previous regional studies …


Population Variation In Fossil Graptolites: A Quantitative Study Based On Single Species Assemblages, Elliott Matthias Mazur 2014 University of Dayton

Population Variation In Fossil Graptolites: A Quantitative Study Based On Single Species Assemblages, Elliott Matthias Mazur

Honors Theses

There are several different types of variation in populations of fossil organisms. These include intra-specific (population) variation, evolutionary variation (specimens on a slab accumulating over thousands of years), and preservational variation. An understanding of the extent and type of variation present in a population is fundamental to biological and paleontological studies. This study examines several populations of fossil graptolites from which population variation can be studied without the influence of the other types, and includes several types of morphometric analyses to examine population variation in several species of fossil graptolites. These analyses include isolating three dimensionally preserved specimens from limestone, …


Near-Surface Internal Melting: A Substantial Mass Loss On Antarctic Dry Valley Glaciers, Matthew J. Hoffman, Andrew G. Fountain, Glen E. Liston 2014 Los Alamos National Laboratory

Near-Surface Internal Melting: A Substantial Mass Loss On Antarctic Dry Valley Glaciers, Matthew J. Hoffman, Andrew G. Fountain, Glen E. Liston

Geology Faculty Publications and Presentations

The McMurdo Dry Valleys, southern Victoria Land, East Antarctica, are a polar desert, and melt from glacial ice is the primary source of water to streams, lakes and associated ecosystems. Previous work found that to adequately model glacier ablation and subsurface ice temperatures with a surface energy-balance model required including the transmission of solar radiation into the ice. Here we investigate the contribution of subsurface melt to the mass balance of (and runoff from) Dry Valley glaciers by including a drainage process in the model and applying the model to three glacier sites using 13years of hourly meteorological data. Model …


Hardystonite From The Desert View Mine, California, James A. Van Fleet, Earl R. Verbeek 2014 Bucknell University

Hardystonite From The Desert View Mine, California, James A. Van Fleet, Earl R. Verbeek

Faculty Journal Articles

The fluorescent mineral hardystonite is confirmed in a specimen from the Desert View Mine, California. Hardystonite had been known only from Franklin, New Jersey for over 100 years.


Peritidal Carbonate Cycles Induced By Carbonate Productivity Variations: A Conceptual Model For An Isolated Early Triassic Greenhouse Platform In South China, Wan Yang, Daniel J. Lehrmann 2014 Missouri University of Science and Technology

Peritidal Carbonate Cycles Induced By Carbonate Productivity Variations: A Conceptual Model For An Isolated Early Triassic Greenhouse Platform In South China, Wan Yang, Daniel J. Lehrmann

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Eustasy has commonly been invoked to explain peritidal carbonate cyclicity, but is difficult to explain cycles formed in a greenhouse climate when eustasy is minimal. We propose that peritidal cycles on an Early Triassic isolated carbonate platform in Guizhou, South China, were formed by hierarchical carbonate productivity variations. Most of the 149 shallowing-upward cycles are typically terminated by flooding over intertidal facies and contain rare supratidal facies and no prolonged subaerial exposure. Low-diversity benthos in the platform interior during the post-end-Permian biotic recovery were sensitive to environmental perturbations, which caused variations in benthic sediment productivity in the subtidal carbonate factory. …


Part I: Neoacadian To Alleghanian Foreland Basin Development And Provenance In The Central Appalachian Orogen, Pine Mountain Thrust Sheet Part Ii: Structural Configuration Of A Modified Mesozoic To Cenozoic Forearc Basin System, South-Central Alaska, Peter Benjamin Robertson 2014 Purdue University

Part I: Neoacadian To Alleghanian Foreland Basin Development And Provenance In The Central Appalachian Orogen, Pine Mountain Thrust Sheet Part Ii: Structural Configuration Of A Modified Mesozoic To Cenozoic Forearc Basin System, South-Central Alaska, Peter Benjamin Robertson

Open Access Theses

Foreland and forearc basins are large sediment repositories that form in response to tectonic loading and lithospheric flexure during orogenesis along convergent plate boundaries. In addition to their numerous valuable natural resources, these systems preserve important geologic information regarding the timing and intensity of deformation, uplift and erosion history, and subsidence history along collisional margins, and, in ancient systems, may provide more macroscopic information regarding climate, plate motion, and eustatic sea level fluctuations. This thesis presents two studies focused in the Paleozoic Appalachian foreland basin system along the eastern United States and in the Mesozoic to Cenozoic Matanuska forearc basin …


On The Amount Of Sediment Deposited In Floodplains From The Mississippi River: A Case Study In Cat Island National Wildlife Refuge, Louisiana, Matthew Smith 2014 Louisiana State University

On The Amount Of Sediment Deposited In Floodplains From The Mississippi River: A Case Study In Cat Island National Wildlife Refuge, Louisiana, Matthew Smith

Honors Capstones

No abstract provided.


Connecting Aerial Gamma Ray Surveys And Geochemical Data, Kara Marsac, Pamela Burnley, Elisabeth Hausrath, Russell Malchow, Daniel Haber 2014 University of Nevada, Las Vegas

Connecting Aerial Gamma Ray Surveys And Geochemical Data, Kara Marsac, Pamela Burnley, Elisabeth Hausrath, Russell Malchow, Daniel Haber

NSTec UNLV Symposium

  • Radiation in the Environment
  • Aerial Gamma Ray Surveys
  • Radiation and Geology
  • Collecting Existing Geochemical Data
  • Rock Unit Geochemistry
  • Model Creation and Comparison


Predictive Modeling Of Radiological Background Using Geochemistry, Daniel Haber, Pamela C. Burnley, Kara Marsac, Russell Malchow, Elisabeth Hausrath, Christopher Adcock 2014 University of Nevada, Las Vegas

Predictive Modeling Of Radiological Background Using Geochemistry, Daniel Haber, Pamela C. Burnley, Kara Marsac, Russell Malchow, Elisabeth Hausrath, Christopher Adcock

NSTec UNLV Symposium

  • Introduction & Background
  • Methods
  • Models
  • Results and Discussion
  • Future Work


Diversion(S) Of The Lower Bear River In Gem Valley, Southeast Idaho, By A Tectono-Volcanic Valve, Susanne U. Jänecke, Robert Q. Oaks Jr. 2014 Utah State University

Diversion(S) Of The Lower Bear River In Gem Valley, Southeast Idaho, By A Tectono-Volcanic Valve, Susanne U. Jänecke, Robert Q. Oaks Jr.

Geosciences Faculty Publications

The lower Bear River of Utah and Idaho was once a tributary of the Snake River that flowed along the NE edge of the Great Basin. Similar biological communities in the upper Bear and Snake Rivers attest to this phase of its history. Basalt flows in Gem Valley, Idaho, diverted the lower Bear River southward into the Bonneville Basin during the late Pleistocene [1] [2] [3]. However, there is no consensus about the timing, location, and mechanism of this major diversion [4] [5]. Landscape and image analysis reveals previously unmapped active normal faults and characterizes Late Pleistocene to Holocene(?) volcanic …


Comparative Sedimentology Of Lake Bonneville And The Great Salt Lake, Kevin Michael McGuire 2014 Brigham Young University - Provo

Comparative Sedimentology Of Lake Bonneville And The Great Salt Lake, Kevin Michael Mcguire

Theses and Dissertations

Ooids of Great Salt Lake, Utah (GSL) have been studied periodically by geologists since the 1960's. These studies have documented the locations of ooid deposits, bulk composition, mineralogy, and internal structural variations of GSL ooids. Ooids have also been identified in sediment cores from lakes predating the Great Salt Lake, but similar descriptions have not been made for these ooids. Samples of ooids from cores in Pilot Valley, UT/NV and Knolls, UT have been obtained, along with samples from the Great Salt Lake at Bridger Bay and Rozel Point. The cortical fabrics and crystal morphologies of these ooids were studied …


Uranium And Radon In Private Bedrock Well Water In Maine: Geospatial Analysis At Two Scales, Qiang Yang, Paul Smitherman, C. T. Hess, Charles W. Culbertson, Robert G. Marvinney, Andrew E. Smith, Yan Zheng 2014 CUNY Graduate Center

Uranium And Radon In Private Bedrock Well Water In Maine: Geospatial Analysis At Two Scales, Qiang Yang, Paul Smitherman, C. T. Hess, Charles W. Culbertson, Robert G. Marvinney, Andrew E. Smith, Yan Zheng

Publications and Research

In greater Augusta of central Maine, 53 out of 1093 (4.8%) private bedrock well water samples from 1534 km2 contained [U] >30 μg/L, the U.S. Environmental Protection Agency’s (EPA) Maximum Contaminant Level (MCL) for drinking water; and 226 out of 786 (29%) samples from 1135 km2 showed [Rn] >4,000 pCi/L (148 Bq/L), the U.S. EPA’s Alternative MCL. Groundwater pH, calcite dissolution and redox condition are factors controlling the distribution of groundwater U but not Rn due to their divergent chemical and hydrological properties. Groundwater U is associated with incompatible elements (S, As, Mo, F, and Cs) in water samples within …


Relational Database Analysis Of Dated Prehistoric Shorelines To Establish Sand Partitioning In Late Holocene Barriers And Beach Plains Of The Columbia River Littoral Cell, Washington And Oregon, Usa, Tamara Causer Linde 2014 Portland State University

Relational Database Analysis Of Dated Prehistoric Shorelines To Establish Sand Partitioning In Late Holocene Barriers And Beach Plains Of The Columbia River Littoral Cell, Washington And Oregon, Usa, Tamara Causer Linde

Dissertations and Theses

Studies of episodic shoreline accretion of the Columbia River Littoral Cell (CRLC) have been ongoing since 1964. In this study, the sediment volumes in the late Holocene barriers and beach plains are compiled and formatted in GIS compatible databases for the four sub-cells of the CRLC.

Initial evaluation involved the creation of a geodatabase of 160 dated retreat scarp positions, that were identified on across-shore GPR and borehole profiles. Ten primary timelines were identified throughout the CRLC (0-4700 ybp) and those were used to develop polygon cells. Elevation, distance measurements, and position information were all linked to the polygon through …


Influence Of Introgression And Geological Processes On Phylogenetic Relationships Of Western North American Mountain Suckers (Pantosteus, Catostomidae), Peter J. Unmack, Thomas E. Dowling, Nina J. Laitinen, Carol L. Secor, Richard L. Mayden, Dennis K. Shiozawa, Gerald R. Smith 2014 Brigham Young University

Influence Of Introgression And Geological Processes On Phylogenetic Relationships Of Western North American Mountain Suckers (Pantosteus, Catostomidae), Peter J. Unmack, Thomas E. Dowling, Nina J. Laitinen, Carol L. Secor, Richard L. Mayden, Dennis K. Shiozawa, Gerald R. Smith

Biological Sciences Faculty Research Publications

Intense geological activity caused major topographic changes in Western North America over the past 15 million years. Major rivers here are composites of different ancient rivers, resulting in isolation and mixing episodes between river basins over time. This history influenced the diversification of most of the aquatic fauna. The genus Pantosteus is one of several clades centered in this tectonically active region. The eight recognized Pantosteus species are widespread and common across southwestern Canada, western USA and into northern Mexico. They are typically found in medium gradient, middle-elevation reaches of rivers over rocky substrates. This study (1) compares molecular data …


Probabilistic Modeling Of Lava Flows: A Hazard Assessment For The San Francisco Volcanic Field, Arizona, Aleeza Harburger 2014 University of South Florida

Probabilistic Modeling Of Lava Flows: A Hazard Assessment For The San Francisco Volcanic Field, Arizona, Aleeza Harburger

USF Tampa Graduate Theses and Dissertations

This study serves as a first step towards a comprehensive hazard assessment for the San Francisco volcanic field in northern Arizona, which can be applied to local response plans and educational initiatives. The primary goal of this thesis is to resolve the conditional probability that, given a lava flow effusing from a new vent in the San Francisco volcanic field, it will inundate the city limits of Flagstaff. The spatial distribution of vents within the San Francisco volcanic field was analyzed in order to execute a lava flow simulation to determine the inundation hazard to Flagstaff. The Gaussian kernel function …


Communicating The Science Of Igcp 591 To The Public, Lewandowski J. Katherine 2014 Eastern Illinois University

Communicating The Science Of Igcp 591 To The Public, Lewandowski J. Katherine

Faculty Research and Creative Activity

Selling the broader impacts of science to funding agencies has become a necessity in a time when competition for grant money is high. While involving students in research is still important for maintaining a pipeline of trained scientists, the bar has been raised and it is increasingly incumbent on us to communicate to the public what is so important about our work. To be competitive in the search for funds, there must be a plan for the science funded to be disseminated to the public. The education and outreach plan for IGCP 591 attempts to appeal to this broader audience …


Seismic Anisotropy And Mantle Flow Beneath The Northern Great Plains Of North America, Bin B. Yang, Stephen S. Gao, Kelly H. Liu, Ahmed A. Elsheikh, Awad A. Lemnifi, Hesham A. Refayee, Youqiang Yu 2014 Missouri University of Science and Technology

Seismic Anisotropy And Mantle Flow Beneath The Northern Great Plains Of North America, Bin B. Yang, Stephen S. Gao, Kelly H. Liu, Ahmed A. Elsheikh, Awad A. Lemnifi, Hesham A. Refayee, Youqiang Yu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

A diverse set of tectonic features and the recent availability of high-quality broadband seismic data from the USArray and other stations on the northern Great Plains of North America provide a distinct opportunity to test different anisotropy-forming mechanisms. A total of 4138 pairs of well-defined splitting parameters observed at 445 stations show systematic spatial variations of anisotropic characteristics. Azimuthally invariant fast orientations subparallel to the absolute plate motion (APM) direction are observed at most of the stations on the Superior Craton and the southern Yavapai province, indicating that a single layer of anisotropy with a horizontal axis of symmetry is …


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