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Hyperspectral Measurements Of Wet, Dry And Saline Soils From The Mcmurdo Dry Valleys: Soil Moisture Properties From Remote Sensing, Joseph S. Levy, Anne Nolin, Andrew G. Fountain, James W. Head 2014 Jackson School of Geoscieces

Hyperspectral Measurements Of Wet, Dry And Saline Soils From The Mcmurdo Dry Valleys: Soil Moisture Properties From Remote Sensing, Joseph S. Levy, Anne Nolin, Andrew G. Fountain, James W. Head

Geology Faculty Publications and Presentations

Soil moisture is a spatially heterogeneous quantity in the McMurdo Dry Valleys of Antarctica that exerts a large influence on the biological community and on the thermal state of Dry Valleys permafrost. The goal of this project was to determine whether hyperspectral remote sensing techniques could be used to determine soil moisture conditions in the Dry Valleys. We measured the spectral reflectance factors of wetted soil samples from the Dry Valleys under natural light conditions and related diagnostic spectral features to surface layer soil moisture content. Diagnostic water absorption features in the spectra at 1.4 mu m and 1.9 mu …


Book Review - Roadside Geology Of Georgia, Melissa E. Johnson 2014 Georgia Regents University

Book Review - Roadside Geology Of Georgia, Melissa E. Johnson

Georgia Library Quarterly

A review of the book, Roadside Geography of Georgia.


Long-Term Protection Of Freshwater Resources Following Co2 Storage, University of North Dakota. Energy and Environmental Research Center 2014 University of North Dakota

Long-Term Protection Of Freshwater Resources Following Co2 Storage, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about mechanisms used to protect freshwater resources following CO2 injection. Outlines U.S. Department of Energy’s research on water safety. [This item is an outdated or superseded version and retained for historical purposes only. It may no longer reflect current information, policies, or practices.]


Evaluation Of Collapse Indicators For Seismically Vulnerable Reinforced Concrete Buildings, Nicholas R. Skok 2014 Purdue University

Evaluation Of Collapse Indicators For Seismically Vulnerable Reinforced Concrete Buildings, Nicholas R. Skok

Open Access Theses

Older reinforced concrete buildings can be prone to column shear and compression failures during earthquakes because of inadequate transverse reinforcement. Cities in seismic areas still have large inventories of older and potentially deficient buildings. To analyze every building and estimate its vulnerability in detail is costly. A simple method to rank quickly older buildings according to their seismic vulnerability is needed to help engineers prioritize the use of resources for rehabilitating the most vulnerable buildings.

Four indicators of building damage or collapse were evaluated using numerical analysis and prior data from building surveys: column index (Hassan & Sozen, 1997), R …


Gps Constraints On The Mw = 7.5 Ometepec Earthquake Sequence, Southern Mexico: Coseismic And Post-Seismic Deformation, Shannon E. Graham, Charles DeMets, Enrique Cabral-Cano, Vladimir Kostoglodov, Andrea Walpersdorf, Nathalie Cotte, Michael Brudzinski, Robert McCaffrey, Luis Salazar-Tlaczani 2014 University of Wisconsin - Madison

Gps Constraints On The Mw = 7.5 Ometepec Earthquake Sequence, Southern Mexico: Coseismic And Post-Seismic Deformation, Shannon E. Graham, Charles Demets, Enrique Cabral-Cano, Vladimir Kostoglodov, Andrea Walpersdorf, Nathalie Cotte, Michael Brudzinski, Robert Mccaffrey, Luis Salazar-Tlaczani

Geology Faculty Publications and Presentations

We use continuous GPS measurements from 31 stations in southernMexico to model coseismic slip and post-seismic deformation from the 2012 March 20 Mw = 7.5 Ometepec earthquake, the first large thrust earthquake to occur below central Mexico during the modern GPS era. Coseismic offsets ranging from ∼280 mm near the epicentre to 5 mm or less at sites far from the epicentre are fit best by a rupture focused between ∼15 and 35 km depth, consistent with an independent seismological estimate. The corresponding geodetic moment of 1.4 × 1020 N·m is within 10 per cent of two independent seismic …


Crustal Accretion And Mantle Geodynamics At Microplates: Constraints From Gravity Analysis And Numerical Modeling, Katherine Ames 2014 Old Dominion University

Crustal Accretion And Mantle Geodynamics At Microplates: Constraints From Gravity Analysis And Numerical Modeling, Katherine Ames

OES Theses and Dissertations

This study investigates crustal accretion and mantle geodynamics at microplates using mantle Bouguer anomaly (MBA) gravity calculations and exploratory numerical models. The Easter and Juan Fernandez microplates are located in the eastern Pacific Ocean along the Pacific, Nazca, and Antarctic plate boundaries. Both microplates formed 3-5 Ma and they are currently rotating clockwise at 15° myr-1 and 9° myr-1,respectively [ e.g., Searle et al., 1993]. The study area also encompasses the Easter /Salas y Gomez mantle plume located near the Easter microplate. Both microplates show a difference in average MBA between their west and east ridges, with …


Loess As A Quaternary Paleoenvironmental Indicator, Daniel R. Muhs, M. A. Prins, B. Machalett 2014 U.S. Geological Survey

Loess As A Quaternary Paleoenvironmental Indicator, Daniel R. Muhs, M. A. Prins, B. Machalett

United States Geological Survey: Staff Publications

Loess (aeolian silt) is widespread in Eurasia and the Americas. Paleowind direction and wind strength can be reconstructed from spatial and temporal trends of loess thickness and particle size. Fossil land snails in loess can reveal much about past climate and vegetation.

Loess is aeolian sediment that is dominated by silt-sized particles. Unlike either coarser dune sand or finer-grained, long-rangetransported dust, loess is relatively poorly sorted, reflecting a combination of transport processes, including saltation, low suspension, and high suspension. Loess can be readily identified in the field; deposits range in thickness from a few centimeters to many tens of meters, …


A New Ankylosaurid Dinosaur From The Upper Cretaceous (Kirtlandian) Of New Mexico With Implications For Ankylosaurid Diversity In The Upper Cretaceous Of Western North America, Victoria M. Arbour, Michael E. Burns, Robert M. Sullivan, Spencer G. Lucas, Amanda K. Cantrell, Joshua Fry, Thomas L. Suazo 2014 University of Alberta

A New Ankylosaurid Dinosaur From The Upper Cretaceous (Kirtlandian) Of New Mexico With Implications For Ankylosaurid Diversity In The Upper Cretaceous Of Western North America, Victoria M. Arbour, Michael E. Burns, Robert M. Sullivan, Spencer G. Lucas, Amanda K. Cantrell, Joshua Fry, Thomas L. Suazo

Geosciences Faculty Publications

A new ankylosaurid (Ankylosauria: Dinosauria), Ziapelta sanjuanensis, gen. et sp. nov., is based on a complete skull, an incomplete first cervical half ring, a possible fragment of the second cervical half ring, and additional fragmentary osteoderms. The holotype specimen is from the Upper Cretaceous (Upper Campanian, Kirtlandian Land-Vertebrate Age) Kirtland Formation (De-na-zin Member) at Hunter Wash, San Juan Basin, in northwestern New Mexico, USA. Diagnostic characters of Ziapelta include: a large, prominent triangular median nasal caputegulum; a mixture of flat and bulbous frontonasal caputegulae; ventrolaterally oriented squamosal horns with a sharp, prominent dorsal keel; and the ventral surface of basicranium …


Analysis, Toxicity, Occurrence And Biodegradation Of Nonylphenol Isomers: A Review, Zhijiang Lu, Jay Gan 2014 University of California, Riverside

Analysis, Toxicity, Occurrence And Biodegradation Of Nonylphenol Isomers: A Review, Zhijiang Lu, Jay Gan

Environmental Science and Geology Faculty Research Publications

Over the last two decades, nonylphenols (NPs) have become to be known as a priority hazardous substance due primarily to its estrogenicity and ubiquitous occurrence in the environment. Nonylphenols are commonly treated as a single compound in the evaluation of their environmental occurrence, fate and transport, treatment or toxicity. However, technical nonylphenols (tNPs) are in fact a mixture of more than 100 isomers and congeners. Recent studies showed that some of these isomers behaved significantly differently in occurrence, estrogenicity and biodegradability. The most estrogenic isomer was about 2 to 4 times more active than tNP. Moreover, the half lives of …


Age Of Barrier Canyon-Style Rock Art Constrained By Cross-Cutting Relations And Luminescence Dating Techniques, Joel L. Pederson, Harriet Cornachione, Steven R. Simms, Reza Sohbati, Tammy M. Rittenour, Andrew S. Murray, Gary Cox 2014 Utah State University

Age Of Barrier Canyon-Style Rock Art Constrained By Cross-Cutting Relations And Luminescence Dating Techniques, Joel L. Pederson, Harriet Cornachione, Steven R. Simms, Reza Sohbati, Tammy M. Rittenour, Andrew S. Murray, Gary Cox

Geosciences Faculty Publications

Rock art compels interest from both researchers and a broader public, inspiring many hypotheses about its cultural origin and meaning, but it is notoriously difficult to date numerically. Barrier Canyon-style (BCS) pictographs of the Colorado Plateau are among the most debated examples; hypotheses about its age span the entire Holocene epoch and previous attempts at direct radiocarbon dating have failed. We provide multiple age constraints through the use of cross-cutting relations and new and broadly applicable approaches in optically stimulated luminescence dating at the Great Gallery panel, the type section of BCS art in Canyonlands National Park, southeastern Utah. Alluvial …


Sedimentology Of Marine Vertebrate Burial In The Miocene Pisco Fm., Peru, Monte A. Fleming 2014 Loma Linda University

Sedimentology Of Marine Vertebrate Burial In The Miocene Pisco Fm., Peru, Monte A. Fleming

Loma Linda University Electronic Theses, Dissertations & Projects

The Miocene Pisco Basin of Peru is known for abundant, well-preserved marine vertebrate fossils (Esperante et al. 2000). Cetacean fossils are particularly abundant—so much so that we were able to locate 10 outcrops containing specimens in cross section, which allowed us to do detailed sedimentological studies of the beds surrounding the whales. We discovered that six of the 10 specimens were buried in channels; the details of the other four burials are too disparate to meaningfully group together in categories. Chapters 3, 4, and 5 describe and discuss the six specimens found in channels, while Appendix A contains descriptions and …


Field Trip Guidebook For The Nebraska Well Drillers Association, Duane A. Eversoll, Matt Joeckel, Lee Orton 2014 University of Nebraska-Lincoln

Field Trip Guidebook For The Nebraska Well Drillers Association, Duane A. Eversoll, Matt Joeckel, Lee Orton

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Economic Geology Of The San Bernardino Mountains, California, Nicolette Deannah Grill 2014 California State University - San Bernardino

Economic Geology Of The San Bernardino Mountains, California, Nicolette Deannah Grill

Electronic Theses, Projects, and Dissertations

The San Bernardino Mountains are well known for their rich mining history, especially, gold in the mid-1800s and the current mining of one of the world’s largest deposits of high purity limestone. The purpose of this study was to compile new, current, and historical data of the major economic resources that are present and mining that has gone on in the San Bernardino Mountains. It is estimated that historical mining of the Holcomb Valley recovered $457,660,000 of gold or about 350,000 troy ounces based on samples collected for this study and 2013 gold price. The current major geologic resource is …


Geophysical Signatures Of Disseminated Iron Minerals: A Proxy For Understanding Subsurface Biophysicochemical Processes, Gamal Z. Abdel Aal, Estella A. Atekwana, Andre Revil 2014 Missouri University of Science and Technology

Geophysical Signatures Of Disseminated Iron Minerals: A Proxy For Understanding Subsurface Biophysicochemical Processes, Gamal Z. Abdel Aal, Estella A. Atekwana, Andre Revil

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Previous studies have linked biogeophysical signatures to the presence of iron minerals resulting from distinct biophysicochemical processes. Utilizing geophysical methods as a proxy of such biophysicochemical processes requires an understanding of the geophysical signature of the different iron minerals. Laboratory experiments were conducted to investigate the complex conductivity and magnetic susceptibility signatures of five iron minerals disseminated in saturated porous media under variable iron mineral content and grain size. Both pyrite and magnetite show high quadrature and inphase conductivities compared to hematite, goethite, and siderite, whereas magnetite was the highly magnetic mineral dominating the magnetic susceptibility measurements. The quadrature conductivity …


Caves In Caves: Evolution Of Post-Depositional Macroholes In Stalagmites, Nurit Shtober-Zisu, Henry P. Schwarcz, Tom Chow, Christopher R. Omelon, Gordon Southam 2014 University of Haifa, Haifa, Israel

Caves In Caves: Evolution Of Post-Depositional Macroholes In Stalagmites, Nurit Shtober-Zisu, Henry P. Schwarcz, Tom Chow, Christopher R. Omelon, Gordon Southam

International Journal of Speleology

In a previous paper (Shtober-Zisu et al., 2012) we described millimeter to centime-sized fluid-free holes within the interiors of stalagmites of widely varying origin. We present here further observations of this phenomenon, using X-ray tomography, macroscopic and microscopic observation of sections of twenty-six stalagmites from various sites in North America and the Caribbean region. We can distinguish three types of cavities in speleothems: primary µm-sized fluid inclusions; mm to cm sized holes, aligned along the stalagmite growth axis which are clearly syngenetic; and µm to cm-sized holes away from the growth axis (“off-axis holes or OAHs”) deeply buried inside their …


Coastal Change Analysis Of Lovells Island Using High Resolution Ground Based Lidar Imagery, Jennifer K. Ly 2014 University of Massachusetts Boston

Coastal Change Analysis Of Lovells Island Using High Resolution Ground Based Lidar Imagery, Jennifer K. Ly

Graduate Masters Theses

Many methods have been employed to study coastline change. These methods range from historical map analysis to GPS surveys to modern airborne LiDAR and satellite imagery. These previously used methods can be time consuming, labor intensive, and expensive and have varying degrees of accuracy and temporal coverage. Additionally, it is often difficult to apply such techniques in direct response to an isolated event within an appropriate temporal framework. Here we utilize a new ground based Canopy Biomass LiDAR (CBL) system built at The University of Massachusetts Boston (in collaboration with the Rochester Institute of Technology) in order to identify and …


Fluid Properties In The Formation Of High-Grade Iron Ore In Northern Minnesota, Elizabeth Drommerhausen 2014 Minnesota State University, Mankato

Fluid Properties In The Formation Of High-Grade Iron Ore In Northern Minnesota, Elizabeth Drommerhausen

Journal of Undergraduate Research at Minnesota State University, Mankato

The Mesabi Iron Range in Northern Minnesota has been a major producer of iron ore for over 100 years. Production has been from the 1.85 – billion-year –old Biwabik Iron Formation, an iron-rich sedimentary rock that is tilted gently to the south. Most of the known high-grade ore lies near the surface and has been already mined. Determining whether more high-grade ore may lie at depth could have significant economic impact on the mining industry in northern Minnesota. To evaluate the likelihood of finding more high-grade iron ore deeper underground, it is important to determine the source of the fluids …


History And Dynamics Of Net Rotation Of The Mantle And Lithosphere, Maxwell L. Rudolph, Shijie Zhong 2014 Portland State University

History And Dynamics Of Net Rotation Of The Mantle And Lithosphere, Maxwell L. Rudolph, Shijie Zhong

Geology Faculty Publications and Presentations

The net rotation of Earth’s lithosphere with respect to the underlying mantle is the longestwavelength component of toroidal flow in the mantle and is sensitive to both mantle buoyancy structure and lateral viscosity variations. The lithospheric net rotation in the geologic past implied by plate reconstructions using a hotspot reference frame for the past 100 Myr is up to five times greater than the presentday rate of lithospheric net rotation. We explore the role of lateral viscosity variations associated with subcontinental keels in producing the lithospheric net rotation for the geologic past and find that the introduction of subcontinental keels …


Composition, Alteration, And Texture Of Fault-Related Rocks From Safod Core And Surface Outcrop Analogs: Evidence For Deformation Processes And Fluid-Rock Interactions, Kelly Keighley Bradbury, Colter R. Davis, John W. Shervais, Susanne U. Janecke, James P. Evans 2014 Utah State University

Composition, Alteration, And Texture Of Fault-Related Rocks From Safod Core And Surface Outcrop Analogs: Evidence For Deformation Processes And Fluid-Rock Interactions, Kelly Keighley Bradbury, Colter R. Davis, John W. Shervais, Susanne U. Janecke, James P. Evans

Geosciences Faculty Publications

We examine the fine-scale variations in mineralogical composition, geochemical alteration, and texture of the fault-related rocks from the Phase 3 whole-rock core sampled between 3,187.4 and 3,301.4 m measured depth within the San Andreas Fault Observatory at Depth (SAFOD) borehole near Parkfield, California. This work provides insight into the physical and chemical properties, structural architecture, and fluid-rock interactions associated with the actively deforming traces of the San Andreas Fault zone at depth. Exhumed outcrops within the SAF system comprised of serpentinite-bearing protolith are examined for comparison at San Simeon, Goat Rock State Park, and Nelson Creek, California. In the Phase …


Investigating The Link Between Surface Water And Groundwater In The Tule Lake Subbasin, Oregon And California, Esther Maria Pischel 2014 Portland State University

Investigating The Link Between Surface Water And Groundwater In The Tule Lake Subbasin, Oregon And California, Esther Maria Pischel

Dissertations and Theses

Water allocation in the upper Klamath Basin of Oregon and California has been challenging. Irrigators have increasingly turned to groundwater to make up for surface water shortages because of shifts in allocation toward in-stream flows for Endangered Species Act listed fishes. The largest increase in groundwater pumping has been in and around the Bureau of Reclamation's Klamath Irrigation Project, which includes the Tule Lake subbasin in the southern part of the upper Klamath Basin. Previous groundwater flow model simulations indicate that water level declines from pumping may result in decreased flow to agricultural drains in the Tule Lake subbasin. Agricultural …


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