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Classifying Microseismicty At Mount St. Helens Using A Large-N Array, Margaret E. Glasgow 2017 University of new mexico

Classifying Microseismicty At Mount St. Helens Using A Large-N Array, Margaret E. Glasgow

Earth and Planetary Sciences ETDs

A dense array of ~1,000 continuously recording, short-period geophones was deployed in the summer of 2014 within ~15 km of Mount St. Helens. Two earthquake catalogs created using reverse time imaging and template detection techniques, increase the detection rate and completeness of the earthquake catalog when compared to the permanent network, Pacific Northwest Seismic Network, catalog. An investigation into event type for ~200 of the earthquake detections leads to the discrimination of two major classification groups, volcano-tectonic and long period. Previous to this study, long period earthquakes had not been identified in the upper crust during a volcanically inactive period …


Fixation And Redistribution Of Arsenic During Early And Late Diagenesis In The Organic Matter-Rich Members Of The Lockatong Formation, Newark Basin, Usa: Implications For The Quality Of Groundwater, Larbi Rddad 2017 CUNY Kingsborough Community College

Fixation And Redistribution Of Arsenic During Early And Late Diagenesis In The Organic Matter-Rich Members Of The Lockatong Formation, Newark Basin, Usa: Implications For The Quality Of Groundwater, Larbi Rddad

Publications and Research

The Byram and Walls Island members in the lower and upper sections, respectively, of the Lockatong Formation in the Newark basin near the border between Pennsylvania and New Jersey were chosen to assess (i) the role of euxinic/anoxic conditions in sequestering arsenic (As) and other trace elements and (ii) the redistribution of these elements during catagenetic transformations. These members are rich in organic matter and host pyrite which occurs as disseminations, small patches, and subparallel veins. e sulfur isotope values of pyrite samples range between -7.5 and 0.5 ‰CDT (average = -3.5‰CDT). e negative δ34S values are indicative of Bacterial …


Investigations Of The Spatial And Temporal Variations Of Sr And Nd Isotopes In Sediments From Two Indian Rivers: Implications To Source Identification, Sonali Pradhan, Jing Zhang, Mark Baskaran, Prabhaker Vasant Shirodkar, Ying Wu, Umesh Kumar Pradhan 2017 School of Resources and Environment Science, East China Normal University, Shanghai, China

Investigations Of The Spatial And Temporal Variations Of Sr And Nd Isotopes In Sediments From Two Indian Rivers: Implications To Source Identification, Sonali Pradhan, Jing Zhang, Mark Baskaran, Prabhaker Vasant Shirodkar, Ying Wu, Umesh Kumar Pradhan

Environmental Science and Geology Faculty Research Publications

Radiogenic isotopes of Sr and Nd provide crucial information on chemical and physical erosion processes, therefore used as tracers for fingerprinting the sources of fluvial sediments. Moreover, elemental geochemistry, 87Sr/86Sr and 143Nd/144Nd signatures in silicate fractions of sediments primarily reflect intricate controls of characteristics and provenance of sediment. A suite of sediment samples collected from two rivers of India, Narmada (large) and Netravati (small) were analyzed for elemental concentrations, 87Sr/86Sr and 143Nd/144Nd in silicate as well as acid-leachable fractions. 87Sr/86Sr in acid-leachable sediment fractions from both the rivers (0.7094 ± 0.0002 for Narmada and 0.7158 ± 0.003 for Netravati) showed …


Δ13c And Δ15n In The Endangered Kemp’S Ridley Sea Turtle Lepidochelys Kempii After The Deepwater Horizon Oil Spill, Kimberly J. Reich, Melania C. López-Castro, Donna J. Shaver, Claire Iseton, Kristen M. Hart, Michael J. Hooper, Christopher J. Schmitt 2017 Texas A&M University at Galveston & Palm Beach Atlantic University

Δ13c And Δ15n In The Endangered Kemp’S Ridley Sea Turtle Lepidochelys Kempii After The Deepwater Horizon Oil Spill, Kimberly J. Reich, Melania C. López-Castro, Donna J. Shaver, Claire Iseton, Kristen M. Hart, Michael J. Hooper, Christopher J. Schmitt

United States Geological Survey: Staff Publications

The Deepwater Horizon explosion in April 2010 and subsequent oil spill released 3.19 × 106 barrels (5.07 × 108 l) of MC252 crude oil into important foraging areas of the endangered Kemp’s ridley sea turtle Lepidochelys kempii (Lk) in the northern Gulf of Mexico (GoM). We measured δ13C and δ15N in scute biopsy samples from 33 Lk nesting in Texas during the period 2010 to 2012. Of these, 27 were equipped with satellite transmitters and were tracked to traditional foraging areas in the northern GoM after the spill. Differences in δ13C between the oldest and newest scute layers from 2010 …


Vegetation Response To Invasive Tamarix Control In Southwestern U.S. Rivers: A Collaborative Study Including 416 Sites, Eduardo Gonzalez, Anna A. Sher, Robert M. Anderson, Robin F. Bay, Daniel W. Bean, Gabriel J. Bissonnete, Berenger Bourgeois, David J. Cooper, Kara Dohrenwend, Kim D. Eichhorst, Hishma El Waer, Deborah K. Kennard, Rebecca Harms-Weissinger, Annie L. Henry, Lori J. Makarick, Steven M. Ostoja, Lindsay V. Reynolds, W. Wright Robinson, Patrick B. Shafroth 2017 Universite de Toulouse & University of Denver

Vegetation Response To Invasive Tamarix Control In Southwestern U.S. Rivers: A Collaborative Study Including 416 Sites, Eduardo Gonzalez, Anna A. Sher, Robert M. Anderson, Robin F. Bay, Daniel W. Bean, Gabriel J. Bissonnete, Berenger Bourgeois, David J. Cooper, Kara Dohrenwend, Kim D. Eichhorst, Hishma El Waer, Deborah K. Kennard, Rebecca Harms-Weissinger, Annie L. Henry, Lori J. Makarick, Steven M. Ostoja, Lindsay V. Reynolds, W. Wright Robinson, Patrick B. Shafroth

United States Geological Survey: Staff Publications

Most studies assessing vegetation response following control of invasive Tamarix trees along southwestern U.S. rivers have been small in scale (e.g., river reach), or at a regional scale but with poor spatial-temporal replication, and most have not included testing the effects of a now widely used biological control. We monitored plant composition following Tamarix control along hydrologic, soil, and climatic gradients in 244 treated and 172 reference sites across six U.S. states. This represents the largest comprehensive assessment to date on the vegetation response to the four most common Tamarix control treatments. Biocontrol by a defoliating beetle (treatment 1) reduced …


Evaporite Karst Geohazards In The Delaware Basin, Texas: Review Of Traditional Karst Studies Coupled With Geophysical And Remote Sensing Characterization, Kevin W. Stafford, Wesley A. Brown, Jon T. Ehrhart, Adam F. Majzoub, Jonathan D. Woodard 2017 Stephen F. Austin State University

Evaporite Karst Geohazards In The Delaware Basin, Texas: Review Of Traditional Karst Studies Coupled With Geophysical And Remote Sensing Characterization, Kevin W. Stafford, Wesley A. Brown, Jon T. Ehrhart, Adam F. Majzoub, Jonathan D. Woodard

International Journal of Speleology

Evaporite karst throughout the Gypsum Plain of west Texas is complex and extensive, including manifestations ranging from intrastratal brecciation and hypogene caves to epigene features and suffosion caves. Recent advances in hydrocarbon exploration and extraction has resulted in increased infrastructure development and utilization in the area; as a result, delineation and characterization of potential karst geohazards throughout the region have become a greater concern. While traditional karst surveys are essential for delineating the subsurface extent and morphology of individual caves for speleogenetic interpretation, these methods tend to underestimate the total extent of karst development and require surficial manifestation of karst …


Assessing Seasonal And Spatial Variability In The Hydrogeochemistry Of Glacial Meltwater In Iceland, Anisha Tuladhar 2017 Western Kentucky University

Assessing Seasonal And Spatial Variability In The Hydrogeochemistry Of Glacial Meltwater In Iceland, Anisha Tuladhar

Masters Theses & Specialist Projects

A detailed comparative geochemical characterization of three different types of Iceland glacial systems was conducted during June, August, and October, 2016. The study was carried out at a total of 11 outlet glacier rivers flowing from the icecaps Vatnajökull, Eyjafjallajökull, and Mýrdalsjökull. A total of 75 grab samples were collected (25 for each sampling period). The hydrogeochemical variations of Icelandic glacial meltwater are influenced by volcanic activity, temporal changes, and geographical location, which differed between the sampling sites within the glaciers and icecaps. Lower pH range, and comparatively higher and variable specific conductivity, SO4, S and F is linked to …


Field-Scale Observations Of A Transient Geobattery Resulting From Natural Attenuation Of A Crude Oil Spill, Jeffrey W. Heenan, Dimitrios Ntarlagiannis, Lee D. Slater, Carol L. Beaver, Silvia Rossbach, Andre Revil, Estella A. Atekwana, Barbara A. Bekins 2017 Missouri University of Science and Technology

Field-Scale Observations Of A Transient Geobattery Resulting From Natural Attenuation Of A Crude Oil Spill, Jeffrey W. Heenan, Dimitrios Ntarlagiannis, Lee D. Slater, Carol L. Beaver, Silvia Rossbach, Andre Revil, Estella A. Atekwana, Barbara A. Bekins

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

We present evidence of a geobattery associated with microbial degradation of a mature crude oil spill. Self-potential measurements were collected using a vertical array of nonpolarizing electrodes, starting at the land surface and passing through the smear zone where seasonal water table fluctuations have resulted in the coating of hydrocarbons on the aquifer solids. These passive electrical potential measurements exhibit a dipolar pattern associated with a current source. The anodic and cathodic reactions of this natural battery occur below and above the smear zone, respectively. The smear zone is characterized by high magnetic susceptibility values associated with the precipitation of …


Synoptic Atmospheric Conditions, Land Cover, And Equivalent Temperature Variations In Kentucky, Dorothy Yemaa Na-Yemeh 2017 Western Kentucky University

Synoptic Atmospheric Conditions, Land Cover, And Equivalent Temperature Variations In Kentucky, Dorothy Yemaa Na-Yemeh

Masters Theses & Specialist Projects

Research has demonstrated that equivalent temperature (TE), which incorporates both the surface air temperature (T) and moist heat content associated with atmospheric moisture, is a better indicator of overall heat content. This thesis follows up on a study that used TE to determine the impacts of land use/land cover and air masses on the atmospheric heat content over Kentucky during the growing season (April-September). The study, which used data from the Kentucky Mesonet, reveals that moist weather types dominate the growing season and, as expected, differences between T and TE are smaller under dry atmospheric conditions …


Naturally Occurring Acid Rock Drainage In The Anaconda-Pintler Mountain Range, Montana: A Case Study Of Geochemistry In Two Streams Flowing From Mount Evans, Margaret Doolittle 2017 Montana Tech

Naturally Occurring Acid Rock Drainage In The Anaconda-Pintler Mountain Range, Montana: A Case Study Of Geochemistry In Two Streams Flowing From Mount Evans, Margaret Doolittle

Graduate Theses & Non-Theses

Mount Evans is located in the Anaconda-Pintler mountain range of southwest Montana approximately 22 km southwest of Anaconda, Montana. Mount Evans appears reddish orange on Google Earth amongst the rest of the mountain range which is a grey white color, indicating the presence of limonite staining and probable sulfide mineralization. In addition, two streams draining opposite sides of the mountain, and either side of the continental divide have conspicuous white coatings on boulders that are clearly visible with Google Earth. During a mineral resource assessment in the 1980s, the USGS suggested that the Mount Evans area could be the top …


Evaluation Of Non-Ionic Surfactants With And Without Hydrogen Peroxide For The In-Situ Remediation Of Napl Contaminants, Charles E. Holada 2017 Western Michigan University

Evaluation Of Non-Ionic Surfactants With And Without Hydrogen Peroxide For The In-Situ Remediation Of Napl Contaminants, Charles E. Holada

Masters Theses

Laboratory studies were conducted on Quillaja saponins and nine other surfactants commonly used to remove non-aqueous phase liquids (NAPLs) from soils and aquifers. The NAPL contaminant tested was diesel fuel. Static batch reactors containing an aged diesel-contaminated soil was treated with saponins and nine other commercially available surfactants to determine how much diesel fuel could be removed with the pore fluids after 1 day and 10 days of contact time. Of all the surfactants tested, saponins achieved the greatest removal of diesel fuel after 1 day and 10 days. There was large disparity in the diesel fuel removed by the …


Mineralogy And Geochemistry Of The Heddleston Porphyry Cu-Mo Deposit, Montana, Ben Schubert 2017 Montana Tech

Mineralogy And Geochemistry Of The Heddleston Porphyry Cu-Mo Deposit, Montana, Ben Schubert

Graduate Theses & Non-Theses

The Heddleston porphyry Cu-Mo deposit is located in Lewis and Clark County, Montana, near the headwaters of the Blackfoot River. It is immediately west of the historic Mike Horse mine, an important producer of Pb-Zn from polymetallic veins and lodes. The Heddleston property was explored extensively by the Anaconda Company in the 1960s and 1970s, but was never mined. Specimens of polished drill core from the deposit are archived in the Anaconda Research Collection at Montana Tech campus. The purpose of this research project was to use the archived samples to examine the geochemistry and mineralogy of the Heddleston and …


Hydrologic And Chemical Interaction Between Waste Dumps And A Flooded Mine Pool At The Combination Mine, Philipsburg District, Montana, Corey Swisher 2017 Montana Tech

Hydrologic And Chemical Interaction Between Waste Dumps And A Flooded Mine Pool At The Combination Mine, Philipsburg District, Montana, Corey Swisher

Graduate Theses & Non-Theses

The Combination Mine, located approximately 12 miles northwest of Philipsburg Montana, was intermittently mined for silver, gold, and copper from 1885 until the 1990s. After the Combination Mine was formally abandoned groundwater seeps downgradient of the mine and waste rock pile were found to be above the regulatory water quality standards. Since the groundwater seeps were downgradient of both the mine pool and waste rock pile the source of the groundwater seeps could have been from the mine pool or shallow flow paths through the waste rock pile. In order to properly plan and execute a remedial action on the …


Sequence Stratigraphic Correlation Of The Bow Island Member Of The Thermopolis Formation Using Surface Outcrop And Subsurface Data, Liberty And Hill Counties, Montana, Michael Vineyard 2017 Montana Tech

Sequence Stratigraphic Correlation Of The Bow Island Member Of The Thermopolis Formation Using Surface Outcrop And Subsurface Data, Liberty And Hill Counties, Montana, Michael Vineyard

Graduate Theses & Non-Theses

The Bow Island Member of the Thermopolis Formation in Montana is a low-pressure gas producer, which formed due to the first (Kiowa-Skull Creek) transgressive–regressive cycles of the Cretaceous Western Interior Seaway.

The Bow Island Member and its correlative units (Viking and Muddy Formations) have been extensively exploited for oil and gas throughout Canada and Wyoming, but remains relatively unmapped in Montana. The area of stratigraphic study is located at section 15, T36N, R5E Liberty County, Montana. This area located on Dafoe Ranch exhibits a moderately exposed stratigraphic section of Cretaceous Thermopolis Formation. The Bow Island Member lies between the Skull …


Characterization Of Granite And Subsequent Ground Control Management Plan At Orphan Boy Mine – Butte, Montana, Emily Rose 2017 Montana Tech

Characterization Of Granite And Subsequent Ground Control Management Plan At Orphan Boy Mine – Butte, Montana, Emily Rose

Graduate Theses & Non-Theses

The Underground Mine Education Center (UMEC) and World Museum of Mining facilities began as shallow underground mines in the 1880’s during the mining boom that populated Butte, Montana. The UMEC is a multi-disciplinary facility that provides an on-campus underground laboratory environment and a place for students to learn and practice practical underground mining techniques; therefore, the longevity of the facility is important to Montana Tech. The goal of this project is to develop a Ground Control Management Plan (GCMP) for the UMEC and World Museum of Mining facilities.

The World Museum of Mining (Orphan Girl) and UMEC (Orphan Boy) facilities …


Structural Reliability Analysis Of Tunneling-Induced Ground Settlement And Damage To Adjacent Buildings: A Case Study Using Moment Methods And Flac2d, Powers Michael 2017 Montana Tech

Structural Reliability Analysis Of Tunneling-Induced Ground Settlement And Damage To Adjacent Buildings: A Case Study Using Moment Methods And Flac2d, Powers Michael

Graduate Theses & Non-Theses

Tunnels are widely used for underground space development in urban areas such as mass transit. However, tunneling in heavily congested areas is a very risky operation that can impose significant damage to adjacent buildings. In the traditional analysis of tunnel structures, the deterministic approach is commonly used. The owners or regulatory agencies establish the limiting ground surface settlement value and angular distortion value for buildings as a means of preventing tunneling-induced failure and damage to adjacent buildings. In addition, significant uncertainties in geotechnical parameters exist in the prediction of tunneling-induced ground settlement and damage to adjacent buildings. Design and analysis …


Supergene Mineralization Of The Continental Pit, Butte, Silver Bow County, Montana, Kyle Eastman 2017 Montana Tech

Supergene Mineralization Of The Continental Pit, Butte, Silver Bow County, Montana, Kyle Eastman

Graduate Theses & Non-Theses

The Butte porphyry Cu-Mo-Ag deposit has been considerably altered by supergene processes that enriched Cu and Ag, and mobilized other metals. Supergene enrichment provided early miners with excellent ore grades, and contributes significantly to current mining operations in Butte. The Continental Pit exhibits the classic leached and enriched vertical zonation that is common in near-surface porphyry systems around the world. Although studied by the Anaconda Copper Mining Company during the mid-20th century, significant and economically relevant questions remain regarding this deposit’s supergene heavy metal geochemistry and its relationship to the local hydrology and tectonic history.

This thesis investigates the paragenesis …


Toward The Development Of A 10be Chronology Of Glaciation In The Mosquito Range, Colorado: A Progress Report, Noah Bensen, Keith A. Brugger 2017 University of Minnesota, Morris

Toward The Development Of A 10be Chronology Of Glaciation In The Mosquito Range, Colorado: A Progress Report, Noah Bensen, Keith A. Brugger

Undergraduate Research Symposium 2017

The Last Glacial Maximum (LGM) in the Rocky Mountain region occurred about 21 ka (20,000 years before present). However, dated glacial chronologies suggest that while LGM glacier advances in individual ranges in Colorado were somewhat synchronous, retreat from their maximum extents was asynchronous, varying between ~20 and 15 ka or later. The precise timing and spatial variation of glacier advance and retreat provides insights into LGM climate change and is necessary to calibrate climate models. To better understand the timing of the LGM in the Mosquito Range in Colorado, we collected 12 samples from granitic boulders on moraine crests in …


Gravity And Passive Seismic Methods Used Jointly For Understanding The Subsurface In A Glaciated Terrain: Dowling And Maple Grove Quadrangles, Barry County, Michigan, Scott A. Feldpausch 2017 Western Michigan University

Gravity And Passive Seismic Methods Used Jointly For Understanding The Subsurface In A Glaciated Terrain: Dowling And Maple Grove Quadrangles, Barry County, Michigan, Scott A. Feldpausch

Masters Theses

The Horizontal to Vertical Spectral Ratio (HVSR) passive, single sensor seismic technique has been used together with gravimetry to study the topography hidden below the glacial drift of two 7.5’ quadrangles in Barry Co., MI. 265 stations were observed with both instruments along roads at nominal spacings of about 0.4 to 0.8 km. Occasional water wells and oil wells with documented penetrations of the base of glacial were used to calibrate the local power law regression calibration. This was also compared with the statewide calibration curve previously established. Results are presented as maps of Simple Bouguer Anomaly, Residual Bouguer Anomaly, …


Hydrologic Response Caused By Wetland Expansion At Huntley Meadows Park In Hybla Valley, Virginia, Stephen Fraser Stone 2017 Old Dominion University

Hydrologic Response Caused By Wetland Expansion At Huntley Meadows Park In Hybla Valley, Virginia, Stephen Fraser Stone

OES Theses and Dissertations

The goal of this study was to understand the effects of wetland expansion across a watershed. The 2013 restoration and expansion of the wetlands at Huntley Meadows Park (Fairfax County, VA) performed by Wetland Studies and Solutions, Inc. provided the opportunity to study this process. The 630 ha park contains more than 364 ha of freshwater emergent and freshwater forested wetlands. The restoration and expansion project used a subsurface vinyl-piling dam that impedes groundwater flow leaving the wetland, thus expanding the existing pond and the surrounding wetland.

This study used a network of more than twenty monitoring instruments making observations …


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