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Ground Motions Induced By The March 11, 2018, Implosion Of The Capital Plaza Tower, Frankfort, Kentucky, N. Seth Carpenter, Michael J. Lynch, Brandon C. Nuttall, Zhenming Wang, Andrew S. Holcomb 2018 University of Kentucky

Ground Motions Induced By The March 11, 2018, Implosion Of The Capital Plaza Tower, Frankfort, Kentucky, N. Seth Carpenter, Michael J. Lynch, Brandon C. Nuttall, Zhenming Wang, Andrew S. Holcomb

Kentucky Geological Survey Report of Investigations

The demolition by implosion of the Capital Plaza Tower in downtown Frankfort provided an opportunity to record seismic waves from a known source of seismic energy in order to observe local ground-motion amplification and resonance within the underlying unconsolidated sediment. The Kentucky Geological Survey deployed three strong-motion accelerographs at approximately equal distances around the tower to record ground motions induced by its collapse. The KGS instruments were installed at sites with different underlying geology: one on bedrock and two on Kentucky River Valley unconsolidated sediments.

Using images captured by a high-speed video camera, with timing synchronized with the clock of ...


Chemical And Statistical Analysis Of Karst Groundwater Basin Signatures - Springfield, Mo, Benjamin E. Lockwood 2018 Missouri State University

Chemical And Statistical Analysis Of Karst Groundwater Basin Signatures - Springfield, Mo, Benjamin E. Lockwood

MSU Graduate Theses

Springfield, MO is located on the Springfield Plateau physiographic province. The Springfield plateau contains a number of Mississippian aged units and is mainly capped by the Burlington-Keokuk Formation. The Burlington-Keokuk is a highly fossiliferous limestone with nodular and interbedded chert. Beneath the Burlington-Keokuk lies the Elsey, Reeds Spring, and Pierson Formations respectively which comprise the Springfield Plateau aquifer hydrostratigraphic unit. Within the Springfield Plateau aquifer, a well-developed karst system includes springs, sinkholes, and caves. The Springfield Plateau aquifer is the predominant source for springs and seeps in the Springfield area. The purpose of this study was to understand the differences ...


Facies Architecture And Controls On Reservoir Behavior In The Turonian Wall Creek Member Of The Frontier Formation, Powder River Basin, Wyoming, Nathan M. La Fontaine 2018 University of Montana, Missoula

Facies Architecture And Controls On Reservoir Behavior In The Turonian Wall Creek Member Of The Frontier Formation, Powder River Basin, Wyoming, Nathan M. La Fontaine

Graduate Student Theses, Dissertations, & Professional Papers

Inter-well heterogeneities influencing fluid migration in deltaic reservoirs are controlled by lateral lithofacies changes and vertical complexities such as low permeability thin-beds. Subsurface tools often cannot predict the spatial and stratigraphic organization of these architectural elements, nor their influence on effective reservoir properties and connectivity. This study integrates sedimentological, stratigraphic, and fluid simulation data to 1) document the facies architecture and depositional evolution of the Turonian Wall Creek Member (WCM) of the Frontier Formation, and 2) quantify the role of multi-scale stratigraphic heterogeneity on reservoir behavior. Upscaled permeability properties derived from fluid simulation of nested, small-scale facies models condition the ...


Performance Of The Grout Curtain At The Kentucky River Lock And Dam No. 8, Robert C. Hatton 2018 University of Kentucky

Performance Of The Grout Curtain At The Kentucky River Lock And Dam No. 8, Robert C. Hatton

Theses and Dissertations--Civil Engineering

Karst bedrock conditions and deterioration of the lock and dam structures have resulted in significant leakage through, underneath, and around Lock and Dam No. 8 on the Kentucky River. During severe droughts, the water surface in Pool No. 8 has been observed to drop below the crest of the dam, resulting in water supply shortages and water quality issues for surrounding communities reliant on the pool. Presently, the primary purpose of Lock and Dam No. 8 is water supply. Pool No. 8 is currently where the cities of Nicholasville (Jessamine County, KY) and Lancaster (Garrard County, KY) draw their water ...


Peer Review Of Teaching Benchmark Portfolio- Geol 100: Introduction To Geology, Mindi Searls 2018 University of Nebraska-Lincoln

Peer Review Of Teaching Benchmark Portfolio- Geol 100: Introduction To Geology, Mindi Searls

UNL Faculty Course Portfolios

No abstract provided.


U-Pb And Hf Isotopic Evidence For An Arctic Origin Of Terranes In Northwestern Washington, Elizabeth R. Schermer, Eric A. Hoffnagle, Edwin H. Brown, George E. Gehrels, William C. McClelland 2018 Western Washington University

U-Pb And Hf Isotopic Evidence For An Arctic Origin Of Terranes In Northwestern Washington, Elizabeth R. Schermer, Eric A. Hoffnagle, Edwin H. Brown, George E. Gehrels, William C. Mcclelland

Geology Faculty and Staff Publications

New field, U-Pb, and Lu-Hf zircon data constrain the geologic history, age, and origin of the Yellow Aster Complex (YAC) in northwestern Washington, providing insight into the tectonic history of this and related Paleozoic arc terranes of the western North American Cordillera. Mapping shows that the oldest YAC rocks consist of quartzofeldspathic paragneiss (meta-arkose) and quartzose calc-silicate paragneiss (metacalcareous siltstone) in gradational contact. Paragneisses are cut by syn-tectonic and post-tectonic intrusions and faulted against granitic orthogneiss. U-Pb zircon results show that (1) maximum depositional ages of paragneisses are Silurian to Early Devonian (432– 390 Ma); (2) detrital zircons from quartzose ...


Biogenic Weathering: Solubilization Of Iron From Minerals By Epilithic Freshwater Algae And Cyanobacteria, George E. Mustoe 2018 Western Washington University

Biogenic Weathering: Solubilization Of Iron From Minerals By Epilithic Freshwater Algae And Cyanobacteria, George E. Mustoe

Geology Faculty and Staff Publications

A sandstone outcrop exposed to freshwater seepage supports a diverse assemblage of photosynthetic microbes. Dominant taxa are two cyanophytes (Oscillatoria sp., Rivularia sp.) and a unicellular green alga (Palmellococcus sp.). Less abundant taxa include a filamentous green alga, Microspora, and the desmid Cosmarium. Biologic activity is evidenced by measured levels of chlorophyll and lipids. Bioassay methods confirm the ability of these microbes to dissolve and metabolize Fe from ferruginous minerals. Chromatographic analysis reveals citric acid as the likely chelating agent; this low molecular weight organic acid is detectable in interstitial fluid in the sandstone, measured as 0.0756 mg/mL ...


Vegetation Responses To Sagebrush-Reduction Treatments Measured By Satellites, Aaron N. Johnston, Erik A. Beever, Jerod A. Merkle, Geneva Chong 2018 Northern Rocky Mountain Science Center

Vegetation Responses To Sagebrush-Reduction Treatments Measured By Satellites, Aaron N. Johnston, Erik A. Beever, Jerod A. Merkle, Geneva Chong

USGS Staff -- Published Research

Time series of vegetative indices derived from satellite imagery constitute tools to measure ecological effects of natural and management-induced disturbances to ecosystems. Over the past century, sagebrush-reduction treatments have been applied widely throughout western North America to increase herbaceous vegetation for livestock and wildlife. We used indices from satellite imagery to 1) quantify effects of prescribed-fire, herbicide, and mechanical treatments on vegetative cover, productivity, and phenology, and 2) describe how vegetation changed over time following these treatments. We hypothesized that treatments would increase herbaceous cover and accordingly shift phenologies towards those typical of grass-dominated systems. We expected prescribed burns would ...


Volcanogenic Pseudo-Fossils From The ~3.48 Ga Dresser Formation, Pilbara, Western Australia, David Wacey, Nora Noffke, Martin Saunders, Paul Guagliardo, David M. Pyle 2018 Old Dominion University

Volcanogenic Pseudo-Fossils From The ~3.48 Ga Dresser Formation, Pilbara, Western Australia, David Wacey, Nora Noffke, Martin Saunders, Paul Guagliardo, David M. Pyle

OEAS Faculty Publications

The ~ 3.48 billion-year-old Dresser Formation, Pilbara Craton, Western Australia, is a key geological unit for the study of Earth's earliest life and the habitats it occupied. Here, we describe a new suite of spheroidal to lenticular microstructures that morphologically resemble some previously reported Archean microfossils. Correlative microscopy shows that these objects have a size distribution, wall ultrastructure, and chemistry that are incompatible with a microfossil origin and instead are interpreted as pyritized and silicified fragments of vesicular volcanic glass. Organic kerogenous material is associated with much of the altered volcanic glass; variable quantities of organic carbon line or ...


Geologic Development And Ongoing Activity Of The Van Zandt Landslide Complex, Northwest Wa, Usa, Geoffrey Malick 2018 Western Washington University

Geologic Development And Ongoing Activity Of The Van Zandt Landslide Complex, Northwest Wa, Usa, Geoffrey Malick

WWU Graduate School Collection

Geomorphic mapping based on high-resolution lidar data indicates that the Van Zandt Landslide Complex (VZLC) has multiple crosscutting debris lobes (up to 51.4 x 106 m3) with long runouts (H/L= 0.14; 0.21) typical of catastrophic rock avalanches. AMS 14C dates from in situ logs and lake sediment cores yield overlapping ages for emplacement of Debris Lobe 2 (1330-1285 cal. yrs. B.P) and Debris Lobe 3 (1300-1285 cal. yrs. B.P.) Although Debris Lobe 3 overlies a portion of Debris Lobe 2, it is possible that emplacement of the two deposits was nearly ...


Modeling The Effects Of Climate Change On Stream Temperature In The Nooksack River Basin, Stephanie E. Truitt 2018 Western Washington University

Modeling The Effects Of Climate Change On Stream Temperature In The Nooksack River Basin, Stephanie E. Truitt

WWU Graduate School Collection

Stream temperatures in mountain streams in the western Cascade Mountains are heavily influenced by factors such as discharge, air temperature, and as in the case of the Nooksack River Basin in northwest Washington State; snow and glacial melt. The Nooksack basin is sensitive to warming climates due to the regions moderate Pacific maritime climate. Previous modeling studies in the upper Nooksack basins indicate a reduction in snowpack and spring runoff, and a recession of glaciers into the 21st century due to global climate change. How stream temperatures will respond to these changes is unknown. We use the Distributed Hydrology ...


Evidence For Ephemeral Middle Eocene To Early Oligocene Greenland Glacial Ice And Pan-Arctic Sea Ice, Aradhna Tripati, Dennis Darby 2018 Old Dominion University

Evidence For Ephemeral Middle Eocene To Early Oligocene Greenland Glacial Ice And Pan-Arctic Sea Ice, Aradhna Tripati, Dennis Darby

OEAS Faculty Publications

Earth's modern climate is defined by the presence of ice at both poles, but that ice is now disappearing. Therefore understanding the origin and causes of polar ice stability is more critical than ever. Here we provide novel geochemical data that constrain past dynamics of glacial ice on Greenland and Arctic sea ice. Based on accurate source determinations of individual ice-rafted Fe-oxide grains, we find evidence for episodic glaciation of distinct source regions on Greenland as far-ranging as ~68°N and ~80°N synchronous with ice-rafting from circum-Arctic sources, beginning in the middle Eocene. Glacial intervals broadly coincide with ...


Visible-To-Near-Infrared Spectral Variability Of Hydrated Sulfates And Candidate Mars Landing Sites: Implications For The Mastcam-Z Investigation On Nasa’S Mars-2020 Rover Mission, Darian Dixon 2018 Western Washington University

Visible-To-Near-Infrared Spectral Variability Of Hydrated Sulfates And Candidate Mars Landing Sites: Implications For The Mastcam-Z Investigation On Nasa’S Mars-2020 Rover Mission, Darian Dixon

WWU Graduate School Collection

The Mars-2020 rover mission will explore an astrobiologically relevant ancient environment on Mars, establish geologic context of the region, assess past habitability, and cache rocks for a future sample return. The Mastcam-Z instrument is a stereoscopic, zoom-enabled multispectral imager that will be critical to these objectives. As one of the mission’s primary reconnaissance tools, Mastcam-Z’s two cameras will acquire red-green-blue (RGB) true-color images and visible-to-near-infrared (VNIR) images with 11 narrowband filters from ~400-1100 nm. Mastcam-Z’s new ~975 nm spectral filter will help characterize the ~950-1000 nm absorption band in hydrated minerals, which has not been resolvable by ...


Biomonitoring In Seattle: Spatial Variation And Source-Determining Of Airborne Pollutants In High-Traffic Areas, Saba Asefa 2018 Western Washington University

Biomonitoring In Seattle: Spatial Variation And Source-Determining Of Airborne Pollutants In High-Traffic Areas, Saba Asefa

WWU Graduate School Collection

Although transportation is a large source of air particulate pollution in the U.S., air quality is currently not routinely monitored on the street level or using methods that could routinely determine particulate composition. In this study, we will use biomonitoring- using biological organisms (in this case tree leaves) as sample collectors- and magnetic characterization of particulate matter (PM) to provide a simple and inexpensive alternative air quality monitoring apparatus that is at the human spatial level, can collect micron-sized particles, and can be found in closely-spaced locations, so that there is a dense area collection network. Magnetic methods such ...


Testing ¹⁰Be Exposure Dating Of Holocene Cirque Moraines Using Glaciolacustrine Sediments In The Sierra Nevada, California, William Cary 2018 Western Washington University

Testing ¹⁰Be Exposure Dating Of Holocene Cirque Moraines Using Glaciolacustrine Sediments In The Sierra Nevada, California, William Cary

WWU Graduate School Collection

An ongoing study attempting to date boulders from Neoglacial moraines across the Sierra Nevada mountain range, CA using high precision cosmogenic radionuclide (CRN) exposure dating has yielded ages that contradict historical records and prior research in the range. To test whether these CRN ages have glacial significance or are merely a function of geomorphic processes that promote inheritance, I collected glaciolacustrine sediment cores to document independent glacier chronologies for the Lyell and Maclure glaciers in Yosemite National Park and the Price glaciers in the Desolation Wilderness. The Lyell glaciolacustrine cores indicate glacial advances from ~1830-1230 cal yr BP and ~610-80 ...


Climate-Change-Driven Accelerated Sea-Level Rise Detected In The Altimeter Era, R. S. Nerem, B. D. Beckley, J. T. Fasullo, B. D. Hamlington, D. Masters, G. T. Mitchum 2018 Old Dominion University

Climate-Change-Driven Accelerated Sea-Level Rise Detected In The Altimeter Era, R. S. Nerem, B. D. Beckley, J. T. Fasullo, B. D. Hamlington, D. Masters, G. T. Mitchum

CCPO Publications

Using a 25-y time series of precision satellite altimeter data from TOPEX/Poseidon, Jason-1, Jason-2, and Jason-3, we estimate the climate-change-driven acceleration of global mean sea level over the last 25 y to be 0.084 ± 0.025 mm/y2. Coupled with the average climate-change-driven rate of sea level rise over these same 25 y of 2.9 mm/y, simple extrapolation of the quadratic implies global mean sea level could rise 65 ± 12 cm by 2100 compared with 2005, roughly in agreement with the Intergovernmental Panel on Climate Change (IPCC) 5th Assessment Report (AR5) model projections.


Metamorphic Evolution Of The Sierra De Maz: Implications For The Timing Of Terrane Accretion On The Western Margin Of Gondwana, Andrew Tholt 2018 Western Washington University

Metamorphic Evolution Of The Sierra De Maz: Implications For The Timing Of Terrane Accretion On The Western Margin Of Gondwana, Andrew Tholt

WWU Graduate School Collection

The Mesoproterozoic MARA terrane of South America has been interpreted to collide and subduct beneath the Gondwana margin of South America in the Cambrian. To test the proposed tectonic model, I combine metamorphic petrology and geochronology along with quantitative thermobarometry to constrain metamorphic events and peak conditions within the Sierra de Maz of the MARA terrane and the adjacent Sierra de Ramaditas. Foliations within the Sierra de Maz are steeply east dipping, with a major sinistral reverse shear zone separating the two major units (Zaino and Maz Complexes) of the northern range. Garnet Lu-Hf records a single metamorphic event in ...


Explaining The Difference In Freeze-Thaw Resistance Of Two Similar “High-Quality” Limestone Aggregates, Evelyn Hussey 2018 Iowa State University

Explaining The Difference In Freeze-Thaw Resistance Of Two Similar “High-Quality” Limestone Aggregates, Evelyn Hussey

Graduate Theses and Dissertations

Several hundred quarries throughout Iowa mine carbonate bedrock for aggregate, which is used in the construction of pavement and structures, as granular surface materials (i.e., “gravel roads”), or as rip rap to prevent erosion. This study focuses on coarse aggregate used in concrete pavement. The Iowa Department of Transportation employs a set of tests to predict the durability of pavement constructed with these aggregates. These tests factor in the bulk elemental chemistry of the carbonate (calcium-rich, magnesium-rich, or a mixture), the alumina percentage (a proxy for clay content), and the pore system (the volume of “micropores”). While these tests ...


Refinement And Utilization Of The Marine Climate Proxy Arctica Islandica: An Ideal Replication Strategy For Stable Isotope Studies And An Investigation Into The Shell Growth And Hydrographic Variability Of Georges Bank (Northwestern Atlantic), Jared Daniel Brenzink Ballew 2018 Iowa State University

Refinement And Utilization Of The Marine Climate Proxy Arctica Islandica: An Ideal Replication Strategy For Stable Isotope Studies And An Investigation Into The Shell Growth And Hydrographic Variability Of Georges Bank (Northwestern Atlantic), Jared Daniel Brenzink Ballew

Graduate Theses and Dissertations

This thesis presents two studies that discuss the further refinement and utilization of the marine climate proxy Arctica islandica. The first study uses a Monte Carlo simulation to examine the relationship between replication and uncertainty for climate reconstructions utilizing oxygen isotopes, carbon isotopes and temperature estimates (derived from the modified Grossman and Ku [1986] equation) from the climate proxy A. islandica. An uncertainty within the 95% confidence interval occurred when using two or three shells. An increase to four shells further reduced the uncertainty to within the 99% confidence interval. Studies that utilize stable isotope ratios from A. islandica shells ...


Deformation Of Fine-Grained Quartz Aggregates By Mixed Diffusion And Dislocation Creep, Caleb Holyoke, Junichi Fukuda 2017 University of Akron

Deformation Of Fine-Grained Quartz Aggregates By Mixed Diffusion And Dislocation Creep, Caleb Holyoke, Junichi Fukuda

Caleb Holyoke

No abstract provided.


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