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Articles 23221 - 23250 of 29957

Full-Text Articles in Geology

Dendrochronological Analysis Of The Martin Cabin Oct 2015

Dendrochronological Analysis Of The Martin Cabin

Historic Structures

Dating historical structures using dendrochronology. The Historical Structures collection consists of reports that are the result of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: Bell, Brandon; Farr, Katherine; Wiesenberg, Nicholas; Wiles, Greg


Ua24 Mcicsl Newsletter - October 2015, Shannon R. Trimboli Education Coordinator Oct 2015

Ua24 Mcicsl Newsletter - October 2015, Shannon R. Trimboli Education Coordinator

MCICSL Newsletter

This issue includes the following:

Mercy Academy Begins Study of Mammoth Cave’s Aquatic Habitat

National Network of Research Learning Centers Releases New Strategic Framework

as well as education and research highlights, MCICSL symposium information and FY16 Education report


Mechanisms And Timing Of Pluton Emplacement In Taranaki Basin, New Zealand Using Three-Dimensional Seismic Analysis, Phillip C. Cammans Oct 2015

Mechanisms And Timing Of Pluton Emplacement In Taranaki Basin, New Zealand Using Three-Dimensional Seismic Analysis, Phillip C. Cammans

Theses and Dissertations

Several off-shore volcano-plutonic complexes are imaged in detail in the Parihaka 3D seismic survey in the Taranaki Basin of New Zealand. Three intrusions were analyzed for this study. Part of the Mohakatino Volcanic Centre (15 to 1.6 Ma), these intrusions have steep sides, no resolvable base reflectors, no internal stratification or structure, and they exhibit doming and faulting in the sedimentary strata above the intrusions. Deformation along the sides is dominated by highly attenuated, dipping strata with dips of 45° or higher that decrease rapidly away from the intrusions. Doming extends several hundred meters from the margins and produced many …


An Investigation Of Groundwater Flow In The Vicinity Of Patoka Dam, Indiana, Lee Anne Bledsoe Oct 2015

An Investigation Of Groundwater Flow In The Vicinity Of Patoka Dam, Indiana, Lee Anne Bledsoe

Masters Theses & Specialist Projects

Several dams throughout the United States have been built on karst terrains, where soluble limestone bedrock has been dissolved to form features such as caves, sinkholes, and underground rivers. In such karst regions, subsurface hydrology can play an integral role in the condition, operation, and safety of dams and should be considered during risk assessment. Patoka Dam, near Jasper, Indiana, is situated on a well-developed karst landscape/aquifer system, faces significant potential challenges, and recently underwent risk assessment. A groundwater flow investigation using multiple fluorescent tracer tests, analysis of water-table elevations, isopach mapping of the Glen Dean Limestone, and spring hydrograph …


Laboratory Manual For Introductory Geology, Bradley Deline, Randa Harris, Karen Tefend Oct 2015

Laboratory Manual For Introductory Geology, Bradley Deline, Randa Harris, Karen Tefend

Geological Sciences and Geography Open Textbooks

This textbook is a comprehensive lab manual for the core curriculum Introductory Geosciences classes with both informational content and laboratory exercises. Topics include basic laws and theories in Geology, the Earth's interior and plate tectonics, water and climate change, igneous rocks and volcanoes, and earthquakes.

Accessible files with optical character recognition (OCR) and auto-tagging provided by the Center for Inclusive Design and Innovation.


Effects Of Changes In Moisture Source And The Upstream Rainout On Stable Isotopes In Precipitation – A Case Study In Nanjing, Eastern China, Y. Tang, H. Pang, W. Zhang, Y. Li, Shuang-Ye Wu, S. Hou Oct 2015

Effects Of Changes In Moisture Source And The Upstream Rainout On Stable Isotopes In Precipitation – A Case Study In Nanjing, Eastern China, Y. Tang, H. Pang, W. Zhang, Y. Li, Shuang-Ye Wu, S. Hou

Department of Earth, Environment and Sustainability Faculty Publications

In the Asian monsoon region, variations in the stable isotopic composition of speleothems have often been attributed to the "amount effect". However, an increasing number of studies suggest that the "amount effect" in local precipitation is insignificant or even non-existent. To explore this issue further, we examined the variability of daily stable isotopic composition (δ18O) in precipitation from September 2011 to November 2014 in Nanjing, eastern China. We found that intra-seasonal variations of δ18O during summer were not significantly correlated with local rainfall amount but could be linked to changes in the moisture source location and rainout processes in the …


North-Central Nebraska Geology: Niobrara River Valley In Brown, Cherry, And Keya Paha Counties, R. M. Joeckel, L. M. Howard, S. T. Tucker Oct 2015

North-Central Nebraska Geology: Niobrara River Valley In Brown, Cherry, And Keya Paha Counties, R. M. Joeckel, L. M. Howard, S. T. Tucker

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Post-Mississippian Tectonic Evolution Of The Nemaha Tectonic Zone And Midcontinent Rift System, Se Nebraska And N Kansas, Caroline M. Burberry, R. Matthew Joeckel, Jesse T. Korus Oct 2015

Post-Mississippian Tectonic Evolution Of The Nemaha Tectonic Zone And Midcontinent Rift System, Se Nebraska And N Kansas, Caroline M. Burberry, R. Matthew Joeckel, Jesse T. Korus

Department of Earth and Atmospheric Sciences: Faculty Publications

The geologic structures of the central Midcontinent of the USA are largely buried and known only from geophysical datasets, coupled with sparse well control and limited outcrop. Such unconstrained geophysical models preclude a deeper assessment of possible continental interior seismic hazards, which have the potential to cause appreciable damage. Within the study area in southeastern Nebraska and northeastern Kansas is an area of elevated seismic risk, with a spatial relationship to the Nemaha Tectonic Zone and the Midcontinent Rift System. Using sequential restorations of three published cross sections within Nebraska and Kansas this study demonstrates that the Nemaha Tectonic Zone …


A Joint Receiver Function And Gravity Study Of Crustal Structure Beneath The Incipient Okavango Rift, Botswana, Youqiang Yu, Kelly H. Liu, Cory A. Reed, Moikwathai Moidaki, Kevin Mickus, Estella A. Atekwana, Stephen S. Gao Oct 2015

A Joint Receiver Function And Gravity Study Of Crustal Structure Beneath The Incipient Okavango Rift, Botswana, Youqiang Yu, Kelly H. Liu, Cory A. Reed, Moikwathai Moidaki, Kevin Mickus, Estella A. Atekwana, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Rifting incorporates the fundamental processes concerning the breakup of continental lithosphere and plays a significant role in the formation and evolution of sedimentary basins. In order to decipher the characteristics of rifting at its earliest stage, we conduct the first teleseismic crustal study of one of the world's youngest continental rifts, the Okavango Rift Zone (ORZ), where the magma has not yet breached the surface. Results from receiver function stacking and gravity modeling indicate that the crust/mantle boundary beneath the ORZ is uplifted by 4-5 km, and the initiation of the ORZ is closely related to lithospheric stretching. Possible decompression …


Eastern Tropical Pacific Climate And El Niño Variability During The Past Millennium, Gerald Thomas Rustic Sep 2015

Eastern Tropical Pacific Climate And El Niño Variability During The Past Millennium, Gerald Thomas Rustic

Dissertations, Theses, and Capstone Projects

The El Niño Southern Oscillation (ENSO) has been implicated in large-scale climate shifts of the past millennia, but paleoclimate records from the dynamically vital eastern equatorial Pacific Ocean (EEP) spanning the past millennium are sparse. This has limited our understanding of tropical Pacific dynamics, leaving questions regarding the source of ENSO variability unanswered. Here I seek to address some of these questions regarding relationship between ENSO and tropical Pacific mean state, and the relationship between the tropical Pacific and large-scale climate. Mean EEP sea surface temperature (SST) for the past millennium was reconstructed using Mg/Ca ratios in Globigerinoides ruber from …


Effects Of Aerial Exposure On Preservation Of Low-Temperature Calothrix Biosignatures In Silica Sinter From Queen's Laundry, Yellowstone National Park, Usa, Shana Kendall Sep 2015

Effects Of Aerial Exposure On Preservation Of Low-Temperature Calothrix Biosignatures In Silica Sinter From Queen's Laundry, Yellowstone National Park, Usa, Shana Kendall

Dissertations and Theses

Mineral-depositing hydrothermal ecosystems, such as the hot springs in Yellowstone National Park, provide an unparalleled opportunity to document how microbial biosignatures form and contribute to the body of evidence indicative of the microbial inhabitants of active hot springs. Mineralization of microbial communities in silica-depositing hot springs can result in the preservation of microbial biofacies in the geologic record. To determine the effects of prolonged aerial exposure on the preservation potential of mid-to-low temperature cyanobacteria dominated microbial communities that are typically permineralized in the siliceous sinter, modern biofacies samples of such communities were collected from the active and inactive parts of …


Effects Of Aerosol On Cloud Water Path: Statistical Method A Potential Source For Divergence In Observation-Based Correlative Studies, Ousmane Sy Savane Sep 2015

Effects Of Aerosol On Cloud Water Path: Statistical Method A Potential Source For Divergence In Observation-Based Correlative Studies, Ousmane Sy Savane

Dissertations, Theses, and Capstone Projects

Divergence between correlative studies involving aerosol and cloud proxies has been thought of in the past as the results of varying physical mechanisms. Although models have supported the existence of variable correlations, from an observational standpoint it is difficult to attribute with confidence the correlations to specific physical mechanisms. We explore a methodology to assess the correlation between cloud water path (CWP) and aerosol optical depth (AOD) using MODIS Aqua retrieved aerosol and cloud properties for regions dominated by different types of aerosol: Non Absorbing Aerosol Dominated Region over land (NAADR_Land), Non Absorbing Aerosol Dominated Region over Ocean (NAADR_Marine), Absorbing …


A Multilevel Analysis Of Neighborhood Socioeconomic Effect On Preterm Births In Georgia, Usa, Wei Tu, Jun Tu, Stuart H. Tedders Sep 2015

A Multilevel Analysis Of Neighborhood Socioeconomic Effect On Preterm Births In Georgia, Usa, Wei Tu, Jun Tu, Stuart H. Tedders

Earth, Environment & Sustainability: Faculty Publications

This study estimates the neighborhood socioeconomic status (SES) effect on the risk of preterm birth (PTB) using multilevel regression (MLR) models. Birth data retrieved from year 2000 and 2010 Georgia Vital Records were linked to their respective census tracts. Principle component analysis (PCA) was performed on nine selected census variables and the first two principal components (Fac1 and Fac2) were used to represent the neighborhood-level SES in the MLR models. Two-level random intercept MLR models were specified using 122,744 and 112,578 live and singleton births at the individual level and 1613 and 1952 census tracts at the neighborhood level, for …


A New Microenvironment For The Formation Of Clay Minerals: The Example Of Authigenic Halloysite-7Å And Gibbsite In A Stalactite From Agios Georgios Cave, Kilkis, North Greece, Elena Ifandi, Basilios Tsikouras, Dimitrios Papoulis, Konstantin Hatzipanagiotou, Aspasia Antonelou Sep 2015

A New Microenvironment For The Formation Of Clay Minerals: The Example Of Authigenic Halloysite-7Å And Gibbsite In A Stalactite From Agios Georgios Cave, Kilkis, North Greece, Elena Ifandi, Basilios Tsikouras, Dimitrios Papoulis, Konstantin Hatzipanagiotou, Aspasia Antonelou

International Journal of Speleology

An unusual authigenic origin for halloysite and gibbsite is reported in a stalactite from Agios Georgios Cave, Kilkis. This speleothem includes mostly pure calcite whereas minor areas of Mg-rich calcite and scarce dolomite are present in four growth phases. Abundant pores are created due to imperfect coalescence of the calcite crystals. Several of them contain detrital muscovite, which was presumably transferred from the dripping water, during the formation of speleothem and has been variably altered to halloysite. Several pores in the stalactite contain different mineral assemblages that we interpret as in situ: halloysite-7Å, halloysite + silica, gibbsite + silica and …


Slip Pulse And Resonance Of The Kathmandu Basin During The 2015 Gorkha Earthquake, Nepal, John Galetzka, Walter Szeliga Sep 2015

Slip Pulse And Resonance Of The Kathmandu Basin During The 2015 Gorkha Earthquake, Nepal, John Galetzka, Walter Szeliga

All Faculty Scholarship for the College of the Sciences

Detailed geodetic imaging of earthquake ruptures enhances our understanding of earthquake physics and associated ground shaking. The 25 April 2015 moment magnitude 7.8 earthquake in Gorkha, Nepal was the first large continental megathrust rupture to have occurred beneath a high-rate (5-hertz) Global Positioning System (GPS) network. We used GPS and interferometric synthetic aperture radar data to model the earthquake rupture as a slip pulse ~20 kilometers in width, ~6 seconds in duration, and with a peak sliding velocity of 1.1 meters per second, which propagated toward the Kathmandu basin at ~3.3 kilometers per second over ~140 kilometers. The smooth slip …


Hydrogeologic Investigation Of A Pumice Aquifer, Fremont/Winema National Forest, Oregon, Jonathan Michael Weatherford Sep 2015

Hydrogeologic Investigation Of A Pumice Aquifer, Fremont/Winema National Forest, Oregon, Jonathan Michael Weatherford

Dissertations and Theses

The middle Holocene cataclysmic eruption of Mount Mazama blanketed Walker Rim, in south central Oregon, with 270 cm to 300 cm of pumice, causing capture of surface water systems by groundwater, stream relocation, and the formation of biologically diverse fens and seasonal wetlands. The pumice aquifer at Round Meadow, an 8.6 km2 basin, hosts both a fen and seasonally ponded wetlands. The Round Meadow watershed lies within a closed basin between the upper Klamath and Deschutes river basins. As the highest meadow at Walker Rim, it is a relatively well-constrained system to study the effects of hydrological disruption.

A …


Ua24 Mcicsl Newsletter - September 2015, Shannon R. Trimboli Education Coordinator Sep 2015

Ua24 Mcicsl Newsletter - September 2015, Shannon R. Trimboli Education Coordinator

MCICSL Newsletter

This issue includes the following:

Citizen Scientists Contribute Over $46,700 of Labor to Mammoth Cave National Park

Federal Agencies Directed to Advance Citizen Science

as well as education and research highlights,and MCICSL strategic planning.


Clustering Data Of Mixed Categorical And Numerical Type With Unsupervised Feature Learning, Dao Lam, Mingzhen Wei, Donald C. Wunsch Sep 2015

Clustering Data Of Mixed Categorical And Numerical Type With Unsupervised Feature Learning, Dao Lam, Mingzhen Wei, Donald C. Wunsch

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Mixed-type categorical and numerical data are a challenge in many applications. This general area of mixed-type data is among the frontier areas, where computational intelligence approaches are often brittle compared with the capabilities of living creatures. In this paper, unsupervised feature learning (UFL) is applied to the mixed-type data to achieve a sparse representation, which makes it easier for clustering algorithms to separate the data. Unlike other UFL methods that work with homogeneous data, such as image and video data, the presented UFL works with the mixed-type data using fuzzy adaptive resonance theory (ART). UFL with fuzzy ART (UFLA) obtains …


Late Quaternary Speleogenesis And Landscape Evolution In A Tropical Carbonate Island: Pango La Kuumbi (Kuumbi Cave), Zanzibar, Nikos Kourampas, Ceri Shipton, William Mills, Ruth Tibesasa, Henrietta Horton, Mark Horton, Mary Prendergast, Alison Crowther, Katerina Douka, Patrick Faulkner, Llorenç Picornell, Nicole Boivin Aug 2015

Late Quaternary Speleogenesis And Landscape Evolution In A Tropical Carbonate Island: Pango La Kuumbi (Kuumbi Cave), Zanzibar, Nikos Kourampas, Ceri Shipton, William Mills, Ruth Tibesasa, Henrietta Horton, Mark Horton, Mary Prendergast, Alison Crowther, Katerina Douka, Patrick Faulkner, Llorenç Picornell, Nicole Boivin

International Journal of Speleology

Kuumbi Cave is one of a group of caves that underlie a flight of marine terraces in Pleistocene limestone in eastern Zanzibar (Indian Ocean). Drawing on the findings of geoarchaeological field survey and archaeological excavation, we discuss the formation and evolution of Kuumbi Cave and its wider littoral landscape. In the later part of the Quaternary (last ca. 250,000 years?), speleogenesis and terrace formation were driven by the interplay between glacioeustatic sea level change and crustal uplift at rates of ca. 0.10-0.20 mm/yr. Two units of backreef/reef limestone were deposited during ‘optimal’ (highest) highstands, tentatively correlated with MIS 7 and …


An Investigation Into Transitions In Clay Mineral Chemistry On Mars, Seth Gainey Aug 2015

An Investigation Into Transitions In Clay Mineral Chemistry On Mars, Seth Gainey

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation is comprised of three studies investigating clay mineralogy on, or near the martian surface, with an introductory chapter, introducing and linking the three studies. Chapter two is on the subject of clay mineral synthesis, including Fe/Mg clay minerals which have been detected at multiple locations across the southern highlands. These Fe/Mg clay minerals have been previously interpreted as forming in anoxic/reducing environments, conducive to the preservation of organic matter. The results of this study suggest that the previous interpretation of Fe/Mg-rich clay as requiring anoxic/reducing conditions may not be accurate, as the minor presence of Mg (below what …


The Science And Practice Of River Restoration, Ellen E. Wohl, Stuart N. Lane, Andrew C. Wilcox Aug 2015

The Science And Practice Of River Restoration, Ellen E. Wohl, Stuart N. Lane, Andrew C. Wilcox

Geosciences Faculty Publications

River restoration is one of the most prominent areas of applied water-resources science. From an initial focus on enhancing fish habitat or river appearance, primarily through structural modification of channel form, restoration has expanded to incorporate a wide variety of management activities designed to enhance river process and form. Restoration is conducted on headwater streams, large lowland rivers, and entire river networks in urban, agricultural, and less intensively human-altered environments. We critically examine how contemporary practitioners approach river restoration and challenges for implementing restoration, which include clearly identified objectives, holistic understanding of rivers as ecosystems, and the role of restoration …


Shaw T. & Alenka ČUk, 2015. Slovene Karst And Caves In The Past, Arrigo A. Cigna Aug 2015

Shaw T. & Alenka ČUk, 2015. Slovene Karst And Caves In The Past, Arrigo A. Cigna

International Journal of Speleology

No abstract provided.


Black Carbon Concentrations In Snow At Tronsen Meadow In Central Washington From 2012 To 2013: Temporal And Spatial Variations And The Role Of Local Forest Fire Activity, Ian Delaney, Susan D. Kaspari, Matthew Jenkins Aug 2015

Black Carbon Concentrations In Snow At Tronsen Meadow In Central Washington From 2012 To 2013: Temporal And Spatial Variations And The Role Of Local Forest Fire Activity, Ian Delaney, Susan D. Kaspari, Matthew Jenkins

Geological Sciences Faculty Scholarship

Characterizing black carbon (BC) concentrations in the seasonal snowpack is of interest because BC deposition on snow can reduce albedo and accelerate melt. In Washington State, USA snowmelt from the seasonal snowpack provides an important source of water resources, but minimal work has been done characterizing BC concentrations in snow in this region. BC concentrations in snow were monitored over two winters (2012 and 2013) at Tronsen Meadow, located near Blewett Pass in the eastern Cascade Mountains in Central Washington, to characterize spatial and temporal variations in BC concentrations, and the processes affecting BC concentrations in the snowpack. BC concentrations …


Dendrochronological Analysis Of The Mann Homestead Aug 2015

Dendrochronological Analysis Of The Mann Homestead

Historic Structures

Dating historical structures using dendrochronology. The Historical Structures collection consists of reports that are the result of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: Wiesenberg, Nicholas


Dendrochronological Analysis Of The Crowe Barn Aug 2015

Dendrochronological Analysis Of The Crowe Barn

Historic Structures

Dating historical structures using dendrochronology. The Historical Structures collection consists of reports that are the result of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: Wiesenberg, Nicholas


Glacier Change On The Three Sisters Volcanoes, Oregon: 1900-2010, Justin George Ohlschlager Aug 2015

Glacier Change On The Three Sisters Volcanoes, Oregon: 1900-2010, Justin George Ohlschlager

Dissertations and Theses

A glacier responds to changes in climate by subsequent retreat and advance as a result of changes in snow inputs and outputs. Understanding these changes is important because shrinking glaciers limit and diminish local water resources. They contribute to alpine runoff in the late-summer months by delaying the maximum runoff until late in the melt season. A comprehensive glacier and perennial snowfield inventory has not been completed for the Three Sisters in Central Oregon. Using aerial photography, Digital Elevation Models (DEMs), previous studies, and historical ground based photographs these glacier and perennial snowfields were defined and their surface area change …


Using Data Visualization Software To Aid In The Analysis Of Geographical Data, Matthew R. Evers, Inzamam Rahaman Aug 2015

Using Data Visualization Software To Aid In The Analysis Of Geographical Data, Matthew R. Evers, Inzamam Rahaman

STAR Program Research Presentations

NASA Web World Wind (Web WW) is designed to visualize and manage geographical data. As a first implementation of visualization and analysis, we designed an application to map earthquake data onto the globe. Portions of this code were merged with application monitoring magnetic field anomalies possibly associated with earthquake precursor activity. Web WW enabled the visualization of the directional vectors from this data to point to the source location of the earthquake. We also developed a prototype urban management application which utilizes OpenStreetMaps to provide simple features such as route navigation, geographical and services information in an area of interest. …


Identifying Glacial Movement Through Fluvial Sediment Analysis, Alexis D. Freeman Aug 2015

Identifying Glacial Movement Through Fluvial Sediment Analysis, Alexis D. Freeman

STAR Program Research Presentations

The primary purpose of this study is to better understand how climate affects river dynamics. It is also important to understand the relationship between glaciers and the transportation of sediments, as this allows us to study changes in transport through time. The studied sediments were gathered from outcrops located in Fresno Ca, off of Friant road. The origin of these sediments are the Sierra Nevada Mountains. Mesozoic metasedimentary and metavolcanic sediments are derived from the foothills, while the granitic sediments are derived from higher up in the mountains. The sediments are characterized by both their degree of rounding, and their …


Ua24 Mcicsl Newsletter - August 2015, Shannon R. Trimboli Education Coordinator Aug 2015

Ua24 Mcicsl Newsletter - August 2015, Shannon R. Trimboli Education Coordinator

MCICSL Newsletter

This issue includes the following:

Bat Night was a success for education and research

MCICSL participated in national network strategic planning

as well as Summer research opportunities


Geo-Needs Focus Group Meetings Report Executive Summary, Heather L. Petcovic, Sheldon P. Turner, Emily Geraghty Ward, Tina Cartwright, Nicole Ladue, David Mogk, Andrew P.K. Bentley, Xai Her Aug 2015

Geo-Needs Focus Group Meetings Report Executive Summary, Heather L. Petcovic, Sheldon P. Turner, Emily Geraghty Ward, Tina Cartwright, Nicole Ladue, David Mogk, Andrew P.K. Bentley, Xai Her

Geological and Environmental Sciences Reports

Geo-Needs Stakeholder Needs Assessment for Broadening Participation in the Geoscience Workforce. Executive summary. The full meeting report is available at http://scholarworks.wmich.edu/geology_reports/1/