Open Access. Powered by Scholars. Published by Universities.®

Geology Commons™

Open Access. Powered by Scholars. Published by Universities.®

29,938 Full-Text Articles 16,127 Authors 6,782,393 Downloads 178 Institutions

All Articles in Geology

Faceted Search

29,938 full-text articles. Page 1241 of 1248.

Spatial Similarities And Differences Of Attributes Of Three Subwatersheds Within The Middle Smoky Hill River Watershed And Their Relationship To Instream Total Suspended Solids, Dustin Fross 2010 Fort Hays State University

Spatial Similarities And Differences Of Attributes Of Three Subwatersheds Within The Middle Smoky Hill River Watershed And Their Relationship To Instream Total Suspended Solids, Dustin Fross

Master's Theses or Doctor of Nursing Practice

The objective of this study was to spatially analyze the attributes of three subwatersheds, Hydrological Unit Code 12 (HUC 12), of the Middle Smoky Hill River Watershed in west-central Kansas and relate the variances of the attributes to the concentrations of total suspended solids (TSS) entering the Smoky Hill River during storm events. This was accomplished by comparing land cover, including cropland, grassland, and urban factors; agricultural practices, such as tillage methods, condition of terraces, and the presence of grass waterways; geomorphology, including soil types, topography, and visible erosion; and lastly, precipitation variance. The three HUC 12s that were studied …


A New Carnosaur (Dinosauria: Theropoda) From The Upper Morrison Formation (Late Jurassic, Tithonian) Of Colorado, Sebastian Dalman 2010 Fort Hays State University

A New Carnosaur (Dinosauria: Theropoda) From The Upper Morrison Formation (Late Jurassic, Tithonian) Of Colorado, Sebastian Dalman

Master's Theses or Doctor of Nursing Practice

A disarticulated skeleton of a theropod from the Late Jurassic (Tithonian) strata of McElmo Canyon in Montezuma County, Colorado was discovered in 1953 by the late J. T. Gregory and D. Techter. For nearly 55 years the specimen remained unnoticed in the collection of the Yale Peabody Museum of Natural History in New Haven, Connecticut. Several cranial and postcranial elements are relatively well preserved and include the premaxilla, maxilla, dentary, teeth, quadratojugal, braincase, metacarpals, partial pubis and ischium, astragalus, partial tibia and fibula, metatarsals, pedal phalanges, and several partially preserved ribs. The specimen represents a new genus and species of …


Book Review: Stars Above, Earth Below: A Guide To Astronomy In The National Parks, T. D. Oswalt 2010 Florida Institute of Technology

Book Review: Stars Above, Earth Below: A Guide To Astronomy In The National Parks, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of Stars Above, Earth Below : a Guide to Astronomy in the National Parks by Tyler Nordgren. Springer/Praxis, 2010 444p, 9781441916488 $29.95.


Upper Cretaceous Peay Bentonites (North-Central Wyoming): Provenance And Tectonics Interpretation From Ash Composition, Nazrul I. Khandaker, Carl F. Vondra, Karl E. Seifert, Malek Shami, Rochelle Cardinale, Thakur Chaturgan 2010 CUNY York College

Upper Cretaceous Peay Bentonites (North-Central Wyoming): Provenance And Tectonics Interpretation From Ash Composition, Nazrul I. Khandaker, Carl F. Vondra, Karl E. Seifert, Malek Shami, Rochelle Cardinale, Thakur Chaturgan

Publications and Research

The Peay bentonites belong to the basal Frontier Formation (Bighorn Basin, north-central Wyoming), primarily outcrop in the Bighorn Basin, rest on an extensively bioturbated sandstone unit, the Peay Sandstone, and are generally the thinner bentonitic unit. Beds of very light gray to greenish gray bentonite are also abundant in the lower Frontier units between Kaycee and Mayoworth (Powder River Basin) and are very rarely as much as 3 m thick. Bentonite occurs within the interstratified shale, sandstone, and siltstone sequences of the lower Frontier unit throughout much of the southwestern Powder River Basin. The purpose of this study is to …


Bedrock Erosion By Root Fracture And Tree Throw: A Coupled Biogeomorphic Model To Explore The Humped Soil Production Function And The Persistence Of Hillslope Soils, Emmanuel Gabet, Simon Mudd 2010 San Jose State University

Bedrock Erosion By Root Fracture And Tree Throw: A Coupled Biogeomorphic Model To Explore The Humped Soil Production Function And The Persistence Of Hillslope Soils, Emmanuel Gabet, Simon Mudd

Faculty Publications

In 1877, G. K. Gilbert reasoned that bedrock erosion is maximized under an intermediate soil thickness and declines as soils become thinner or thicker. Subsequent analyses of this “humped” functional relationship proposed that thin soils are unstable and that perturbations in soil thickness would lead to runaway thinning or thickening of the soil. To explore this issue, we developed a numerical model that simulates the physical weathering of bedrock by root fracture and tree throw. The coupled biogeomorphic model combines data on conifer population dynamics, rootwad volumes, tree throw frequency, and soil creep from the Pacific Northwest (USA). Although not …


Geogram 2010, David J. Keeling Editor, WKU Department of Geography and Geology 2010 Western Kentucky University

Geogram 2010, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.


Experimental Estimation Of The Gpr Groundwave Sampling Depth, Katherine R. Grote, Taylor Crist, Crystal Nickel 2010 Missouri University of Science and Technology

Experimental Estimation Of The Gpr Groundwave Sampling Depth, Katherine R. Grote, Taylor Crist, Crystal Nickel

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Monitoring near-surface soil water content is essential for efficient water management and for understanding hydrologic processes in soils. Ground-penetrating radar (GPR) groundwaves are an approach that can be used to monitor the near-surface soil water content, but the efficacy of this technique is currently limited by the uncertainty surrounding the groundwave sampling depth. This research experimentally determines the sampling depth of GPR groundwaves under dry and saturated conditions in a sandy soil. Data were acquired using 250, 500, and 1000 MHz antennas within an experimental tank containing soil layers of contrasting electromagnetic velocities. Results show that the groundwave sampling depth …


Comparison Of Ice Core Dissolved Organic Matter From A Greenland Ice Core By Nanospray Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, Joshua Jeremiah Shiloh Marsh 2010 Old Dominion University

Comparison Of Ice Core Dissolved Organic Matter From A Greenland Ice Core By Nanospray Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, Joshua Jeremiah Shiloh Marsh

Chemistry & Biochemistry Theses & Dissertations

Recent studies of ice cores have embarked on the task of determining the classes of dissolved organic matter (DOM) present in melt-water from the cores collected in numerous locations in the northern and southern hemispheres. This DOM originally derives from wet precipitation and is thought to reflect atmospheric organic matter derived from anthropogenic and non-anthropogenic sources. Because the amount of DOM is so low, previous studies have necessarily used large sample volumes (greater than 500 mL) to concentrate sufficient ice core DOM necessary for mass spectral analysis. Solid phase extraction (SPE) with C18 resins was followed by evaporative concentration …


Geospatial Data Portals: Librarians Add Expertise In The Development Of Gis Metadata Catalogs, Adonna Fleming 2010 University of Nebraska-Lincoln

Geospatial Data Portals: Librarians Add Expertise In The Development Of Gis Metadata Catalogs, Adonna Fleming

University of Nebraska-Lincoln Libraries: Faculty Publications

Searching a geospatial data catalog can be frustrating for many GIS data users. Geospatial data catalogs are built on records created to a specific metadata standard, such as ISO 19115. The search query is often limited to searching a few tags within the record, such as title, publisher, spatial extent, content theme, and content type. GIS personnel tend to create metadata records with little thought into how it will be discovered by others. On the other hand, library catalogs are developed for a broad spectrum of users with varying knowledge of the subject. Librarians can bring this expertise in creating …


A Trekker’S Guide To The Khumbu Himalaya: Trailside Geology Along The Everest Base Camp Trek, Brigit Anderson 2010 SIT Study Abroad

A Trekker’S Guide To The Khumbu Himalaya: Trailside Geology Along The Everest Base Camp Trek, Brigit Anderson

Independent Study Project (ISP) Collection

The Himalaya is the youngest and highest mountain range in the world. It thus provides a wonderful field lab for studying the mountain building process in action. The trek in the Khumbu (northeastern Nepal) from Lukla to Everest Base Camp takes you through the Higher Himalaya and some interesting geological features. This project gives an introduction to the larger Himalaya geology and more specifically geology of the Khumbu Region. It then follows the Lukla-Everest Base Camp (EBC) trekking route pointing out interesting geologic features along the way. Some of the concepts explained in this project are somewhat technical. For this …


Sensitivity Of Geoelectrical Measurements To The Presence Of Bacteria In Porous Media, Gamal Z. Abdel Aal, Estella A. Atekwana, Silvia Rossbach, D. Dale Werkema 2010 Missouri University of Science and Technology

Sensitivity Of Geoelectrical Measurements To The Presence Of Bacteria In Porous Media, Gamal Z. Abdel Aal, Estella A. Atekwana, Silvia Rossbach, D. Dale Werkema

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

We investigated the sensitivity of low-frequency electrical measurements (0.1-1000 Hz) to (1) microbial cell density, (2) live and dead cells, and (3) microbial attachment onto mineral surfaces of clean quartz sands and iron oxide-coated sands. Three strains of Pseudomonas aeruginosa PAO1 (wild type and rhlA and pilA mutant) with different motility and attachment properties were used. Varying concentrations of both live and dead cells of P. aeruginosa wild type in sand columns showed no effect on the real conductivity component (σ′). However, the imaginary conductivity component (σ″) increased linearly with increasing concentrations of live cells in sand columns, whereas minimal …


Characterization Of Soil Water Content Variability And Soil Texture Using Gpr Groundwave Techniques, Katherine R. Grote, Cale T. Anger, Bridget Kelly, Susan Sharpless Hubbard, Yoram N. Rubin 2010 Missouri University of Science and Technology

Characterization Of Soil Water Content Variability And Soil Texture Using Gpr Groundwave Techniques, Katherine R. Grote, Cale T. Anger, Bridget Kelly, Susan Sharpless Hubbard, Yoram N. Rubin

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Accurate characterization of near-surface soil water content is vital for guiding agricultural management decisions and for reducing the potential negative environmental impacts of agriculture. Characterizing the near-surface soil water content can be difficult, as this parameter is often both spatially and temporally variable, and obtaining sufficient measurements to describe the heterogeneity can be prohibitively expensive. Understanding the spatial correlation of near-surface soil water content can help optimize data acquisition and improve understanding of the processes controlling soil water content at the field scale. In this study, ground penetrating radar (GPR) methods were used to characterize the spatial correlation of water …


Design Of A Conditioner For Smoothing Wind Turbine Output Power, Murali Bottu, Mariesa Crow, A. Curt Elmore 2010 Missouri University of Science and Technology

Design Of A Conditioner For Smoothing Wind Turbine Output Power, Murali Bottu, Mariesa Crow, A. Curt Elmore

Electrical and Computer Engineering Faculty Research & Creative Works

As a result of wind speed intermittency, highly variable wind power output can adversely impact local loads. We propose a conditioner to smooth the variable wind power by utilizing the energy of an ultracapacitor. The conditioner is based on a single phase voltage source inverter (VSI) connected between the grid interconnection point and the ultracapacitor. The shunt VSI injects or absorbs active power from the line to smooth the wind power by utilizing the short term storage capabilities of the ultracapacitor. The ultracapacitor is connected to the DC link through a DC-DC converter, which maintains the voltage of the DC …


Great Basin Center For Geothermal Energy, Wendy Calvin 2010 University of Nevada, Reno

Great Basin Center For Geothermal Energy, Wendy Calvin

Nevada Renewable Energy Consortium Meeting

The second annual Nevada Renewable Energy Consortium meeting took place at UNLV on August 20. The meeting focused on the current three NVREC program areas: Solar, Biomass and Geothermal. Presentations were made by participating entities and a poster session followed.


Chronostratigraphy And Paleontology Of The Mid-Cretaceous Wayan Formation Of Eastern Idaho, With A Description Of The First Oryctodromeus Specimens From Idaho, Laurel J. Krumenacker 2010 Brigham Young University - Provo

Chronostratigraphy And Paleontology Of The Mid-Cretaceous Wayan Formation Of Eastern Idaho, With A Description Of The First Oryctodromeus Specimens From Idaho, Laurel J. Krumenacker

Theses and Dissertations

The mid-Cretaceous Wayan Formation of Idaho consists of floodplain-deposited siltstones and mudstones, with subordinate fluvial sandstones and conglomerates. Deposition occurred in a tectonic foredeep at the toe of the Sevier thrust complex. Measurement of two incomplete and one complete section indicates a thickness of roughly 1,344 meters in the study area. No laterally extensive marker beds are present but the lower Wayan contains distinct chert pebble conglomerates, and the middle Wayan may contain a higher relative abundance of fluvial sandstone. Known fossil localities are limited to the lower and middle portions of the formation. The Wayan Formation, as currently defined, …


Secondary Enrichment Of Copper At The Madison Gold Skarn Deposit, Silver Star District, Montana, Christopher H. Gammons, Jill Sotendahl, Dan Everett 2010 Montana Tech

Secondary Enrichment Of Copper At The Madison Gold Skarn Deposit, Silver Star District, Montana, Christopher H. Gammons, Jill Sotendahl, Dan Everett

Geological Engineering

Secondary Enrichment of Copper at the Madison Gold Skarn Deposit, Silver Star District, Montana. This paper focuses on the chemical reactions responsible for secondary enrichment of copper...we argue that most of the secondary Cu enrichment occurred during a late hydrothermal event that replaced the high temperature skarn mineral assemblage with hematitic jasperoid. Evidence favoring this "hypogene" Cu enrichment hypothesis is presented.


Spatial Variations Of Crustal Characteristics Beneath The Hoggar Swell, Algeria, Revealed By Systematic Analyses Of Receiver Functions From A Single Seismic Station, Kelly H. Liu, Stephen S. Gao 2010 Missouri University of Science and Technology

Spatial Variations Of Crustal Characteristics Beneath The Hoggar Swell, Algeria, Revealed By Systematic Analyses Of Receiver Functions From A Single Seismic Station, Kelly H. Liu, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Hoggar swell in Algeria is one of the significant massifs of northwest Africa. The paucity of high-resolution geophysical studies of the crust and mantle beneath the massifs is mostly responsible for the heated debates about the depth of the source region of the Cenozoic volcanism and the closely related uncertainty about the mechanism that formed and maintains the high elevation of the swells. Here we report results from a systematic study of 1386 high-quality receiver functions (RFs) recorded by station TAM, the only permanent broadband seismic station on the Hoggar swell. The resulting crustal thickness is about 34 km …


Clay Mineral Cycles Identified By Diffuse Spectral Reflectance In Quaternary Sediments From The Northwind Ridge: Implications For Glacial-Interglacial Sedimentation Patterns In The Arctic Ocean, Lyanne N. Yurco, Joseph D. Ortiz, Leonid Polyak, Dennis A. Darby, Kevin A. Crawford 2010 Old Dominion University

Clay Mineral Cycles Identified By Diffuse Spectral Reflectance In Quaternary Sediments From The Northwind Ridge: Implications For Glacial-Interglacial Sedimentation Patterns In The Arctic Ocean, Lyanne N. Yurco, Joseph D. Ortiz, Leonid Polyak, Dennis A. Darby, Kevin A. Crawford

OES Faculty Publications

A Quaternary record of fine-grained sediment composition is used to investigate Arctic Ocean climate variability on glacial-interglacial time scales. Diffuse spectral reflectance data from sediment core P1-92AR-P25 from the Northwind Ridge, north of Alaska, demonstrates cyclic variations in mineralogy. Varimax-rotated R-mode factor analysis of down-core data revealed three major mineralogical assemblages, which were then compared with the content of manganese, a proxy for basin ventilation, and thus glacial-interglacial cycles. Results indicate that factor 1, a smectite + chlorite clay assemblage, was delivered to the core site during interglacials, either by fluvial discharge or sea-ice drift from Siberian rivers or inflow …


Thermal History Of The Ecstall Pluton From 40Ar/39Ar Geochronology And Thermal Modeling, Sarah J. Brownlee, Paul R. Renne 2010 University of California - Berkeley

Thermal History Of The Ecstall Pluton From 40Ar/39Ar Geochronology And Thermal Modeling, Sarah J. Brownlee, Paul R. Renne

Environmental Science and Geology Faculty Research Publications

New 40Ar/39Ar thermochronology results and thermal modeling support the hypothesis of Hollister et al. (2004), that reheating of the mid-Cretaceous Ecstall pluton by intrusion of the Coast Mountains Batholith (CMB) was responsible for spatially variable remagnetization of the Ecstall pluton. 40Ar/39Ar ages from hornblende and biotite from 12 locations along the Skeena River across the northern part of the Ecstall pluton decrease with proximity to the Quottoon plutonic complex, the nearest member of the CMB to the Ecstall pluton. The oldest 40Ar/39Ar ages are found farthest from the Quottoon plutonic …


Hydromechanical Interference Slug Tests In A Fractured Biotite Gneiss, Trever Slack 2010 Clemson University

Hydromechanical Interference Slug Tests In A Fractured Biotite Gneiss, Trever Slack

All Theses

Fractures are ubiquitous in the shallow crust and they commonly control the flow and storage of fluids in rock. Estimating transmission and storage properties resulting from fractures is commonly accomplished by interpreting the pressure signals caused by stressing an aquifer during a pumping or slug test. Fractures deform in response to pressure changes during well tests, and measuring and interpreting the deformation along with the pressure change is a way to potentially increase the information about storage and transmission properties. Tests where the pressure and deformation are coupled are called hydromechanical well tests. Previous investigations have focused on the effects …


Digital Commons powered by bepress