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Discovery Of Possible Paleotsunami Deposits In Pangandaran And Adipala, Java, Indonesia Using Grain Size, Xrd, And 14C Analyses, Kevin L. Stuart 2018 Brigham Young University

Discovery Of Possible Paleotsunami Deposits In Pangandaran And Adipala, Java, Indonesia Using Grain Size, Xrd, And 14C Analyses, Kevin L. Stuart

All Theses and Dissertations

Grain size, 14C age, and X-ray diffraction (XRD) analyses of sediments indicate possible tsunami deposits on the southern coast of Java near Pangandaran and Adipala. Previous studies that have described known recent and paleotsunami deposits were used for comparison. Fining-upward grain size trends, interbedded sand and mud, sediment composition, and trends in heavy mineral abundances are among the characteristics used for tsunami deposit identification. At Batu Kalde, an archaeological site south of Pangandaran, a layer of aragonitic sand with marine fossils was found atop a layer of archaeological fragments at an elevation of ~2-5 m. It is likely this ...


Paleo-Environmental Interpretations And Weathering Effects Of The Mowry Shale From Geochemical Analysis Of Outcrop Samples In The Western Margin Of The Wind River Basin Near Lander, Wyoming, Trevor Robinson Tuttle 2018 Brigham Young University

Paleo-Environmental Interpretations And Weathering Effects Of The Mowry Shale From Geochemical Analysis Of Outcrop Samples In The Western Margin Of The Wind River Basin Near Lander, Wyoming, Trevor Robinson Tuttle

All Theses and Dissertations

The Cretaceous Mowry Shale is an organic-rich, siliceous marine shale, and as such is a known source rock in the Western United States. Studies have documented that total organic carbon (TOC) in the Wind River Basin, Wyoming increases to the southeast. These studies cover large areas with limited sample sets. In this study, over 250 samples were collected near Lander, Wyoming to address spatial heterogeneity of TOC within the Mowry Shale at a much finer scale than previously examined. Samples were collected along five vertical sections at three localities, and following correlation of the vertical sections, which was strongly aided ...


Experimental Study Of Gravitational Mixing Of Supercritical Co2, Dennis L. Newell, J. William Carey, Scott N. Backhaus, Peter Lichtner 2018 Utah State University

Experimental Study Of Gravitational Mixing Of Supercritical Co2, Dennis L. Newell, J. William Carey, Scott N. Backhaus, Peter Lichtner

Geology Faculty Publications

CO2 injection into saline aquifers for sequestration will initially result in buoyant supercritical (sc)CO2 trapped beneath the caprock seal. During this period, there is risk of CO2 migration out of the reservoir along wellbore defects or fracture zones. Dissolution of the scCO2 plume into brine results in solubility trapping and reduces this risk, but based on diffusion alone, this mechanism could take thousands of years. Gravitational (density-induced) mixing of CO2-saturated brine is shown to significantly accelerate this process in computational studies, but few experimental efforts have confirmed the phenomenon. Here, constant-pressure, 3-dimensional bench-scale ...


Stratigraphy Of The Upper Silurian To Middle Devonian, Southwestern Ontario, Shuo Sun 2018 The University of Western Ontario

Stratigraphy Of The Upper Silurian To Middle Devonian, Southwestern Ontario, Shuo Sun

Electronic Thesis and Dissertation Repository

The upper Silurian–Middle Devonian succession was dominated by carbonate and evaporite deposits, with minor siliciclastic sedimentation, and a significant hiatus across the Siluro-Devonian (S-D) boundary in southwestern Ontario. The stratigraphic units include, in ascending order: Late Silurian Bass Islands/Bertie formations and Salina G Unit, the Devonian Oriskany Formation, Bois Blanc Formation (including Springvale Member), Detroit River Group (including the Lucas, Amherstburg and Sylvania formations), Onondaga Formation, and Dundee Formation.

Below the S-D unconformity, the upper Silurian Bass Islands/Bertie formations are predominantly dolostone of peritidal-sabkha origin and episodic subaerial exposure. Revised stratigraphic correlation shows that the Bertie Formation ...


Evidence For Cyclical Fractional Crystallization, Recharge, And Assimilation In Basalts Of The Kimama Drill Core, Central Snake River Plain, Idaho: 5.5-Million-Years Of Petrogenesis In A Mid-Crustal Sill Complex, Katherine E. Potter, John W. Shervais, Eric H. Christiansen, Scott K. Vetter 2018 Utah State University

Evidence For Cyclical Fractional Crystallization, Recharge, And Assimilation In Basalts Of The Kimama Drill Core, Central Snake River Plain, Idaho: 5.5-Million-Years Of Petrogenesis In A Mid-Crustal Sill Complex, Katherine E. Potter, John W. Shervais, Eric H. Christiansen, Scott K. Vetter

Geology Faculty Publications

Basalts erupted in the Snake River Plain of central Idaho and sampled in the Kimama drill core link eruptive processes to the construction of mafic intrusions over 5.5 Ma. Cyclic variations in basalt composition reveal temporal chemical heterogeneity related to fractional crystallization and the assimilation of previously-intruded mafic sills. A range of compositional types are identified within 1,912 m of continuous drill core: Snake River olivine tholeiite (SROT), low K SROT, high Fe-Ti, and evolved and high K-Fe lavas similar to those erupted at Craters of the Moon National Monument. Detailed lithologic and geophysical logs document 432 flow ...


An Assessment Of Concrete Over Asphalt Pavement Using Both The Ultrasonic Surface Wave And Impact Echo Techniques, Mengxing Li, Neil Lennart Anderson, Lesley Sneed, Xin Kang 2018 Missouri University of Science and Technology

An Assessment Of Concrete Over Asphalt Pavement Using Both The Ultrasonic Surface Wave And Impact Echo Techniques, Mengxing Li, Neil Lennart Anderson, Lesley Sneed, Xin Kang

Lesley Sneed, Ph.D., P.E.

A portable seismic property analyzer (PSPA) was used to simultaneously acquire both ultrasonic surface wave (PSPA-USW) and impact-echo (PSPA-IE) data at predetermined locations along a section of multi-layered pavement. The pavement consisted of a basal concrete layer (~220 mm), an intervening layer of hot-mix asphalt (~60 mm), and a concrete overlay (~220 mm). The section of multi-layered pavement was cored at multiple PSPA test locations for verification purposes. The conditions of the extracted cores were assessed visually, and the static elastic modulus, as well as the compressional wave velocity of each concrete overlay core, were measured in the laboratory. Results ...


Highway Construction Or Stream Destruction: A Water Quality Analysis In The Black Warrior Basin, Walker County, Alabama, Cayla Baughn 2018 Western Kentucky University

Highway Construction Or Stream Destruction: A Water Quality Analysis In The Black Warrior Basin, Walker County, Alabama, Cayla Baughn

Honors College Capstone Experience/Thesis Projects

In 2012, residents along Freeman Branch Creek in Eldridge, Alabama observed unusual orange discoloration along the stream and on stream vegetation; an unprecendented black veneer coating pebbles along the streambed; and life in the stream seemed to have vanished. Freeman Branch Creek is located in Walker County, Alabama, which is known for its production of coal and natural gas from the underlying Pennsylvanian-aged Pottsville Formation, which is the uppermost geologic layer within the the Black Warrior Basin. Concerns for environmental safety related to intensive mining operations include the concern that shallow aquifers will be contaminated by mining in deep reservoir ...


Evidence Of The 1762 Arakan And Prior Earthquakes In The Northern Sunda Subduction, Dhiman Ranjan Mondal 2018 The Graduate Center, City University of New York

Evidence Of The 1762 Arakan And Prior Earthquakes In The Northern Sunda Subduction, Dhiman Ranjan Mondal

All Dissertations, Theses, and Capstone Projects

The objective of this dissertation is to understand the seismic hazard associated with Arakan segment of the northern Sunda subduction along SE Bangladesh. In order to do that, it is necessary to document geologic evidence for the 1762 Arakan earthquake and prior events, to help estimate the recurrence interval (repeat time) for that earthquake. Historical records described that the 1762 earthquake caused extensive damage along the Arakan segment of the Sunda subduction system. But the geologic evidence for the earthquake farther north is necessary to better understand its associated seismic hazard to the densely populated nation of Bangladesh. This dissertation ...


Elastic Geothermobarometry: Corrections For The Geometry Of The Host-Inclusion System, M. L. Mazzucchelli, Pamela Burnley, R. J. Angel, S. Morganti, M. C. Domeneghetti, F. Nestola, M. Alvaro 2018 University of Pavia

Elastic Geothermobarometry: Corrections For The Geometry Of The Host-Inclusion System, M. L. Mazzucchelli, Pamela Burnley, R. J. Angel, S. Morganti, M. C. Domeneghetti, F. Nestola, M. Alvaro

Geoscience Faculty Publications

Elastic geothermobarometry on inclusions is a method to determine pressure-temperature conditions of mineral growth independent of chemical equilibrium. Because of the difference in their elastic properties, an inclusion completely entrapped inside a host mineral will develop a residual stress upon exhumation, from which one can back-calculate the entrapment pressure. Current elastic geobarometric models assume that both host and inclusion are elastically isotropic and have an ideal geometry (the inclusion is spherical and isolated at the center of an infinite host). These conditions do not commonly occur in natural rocks, and the consequences for inclusion pressures can only be quantified with ...


Discovery And Geology Of The Guinness World Record Lake Copper, Lake Superior, Michigan, Theodore J. Bornhorst, Robert Barron 2018 Michigan Technological University

Discovery And Geology Of The Guinness World Record Lake Copper, Lake Superior, Michigan, Theodore J. Bornhorst, Robert Barron

Theodore J. Bornhorst

No abstract provided.


Genuine Faculty-Mentored Research Experiences For In-Service Science Teachers: Increases In Science Knowledge, Perception, And Confidence Levels, Christine E. Cutucache, Heather D. Leas, Neal F. Grandgenett, Kari L. Nelson, Steven N. Rodie, Robert Duncan Shuster, Chris Schaben, William E. Tapprich 2018 University of Nebraska at Omaha

Genuine Faculty-Mentored Research Experiences For In-Service Science Teachers: Increases In Science Knowledge, Perception, And Confidence Levels, Christine E. Cutucache, Heather D. Leas, Neal F. Grandgenett, Kari L. Nelson, Steven N. Rodie, Robert Duncan Shuster, Chris Schaben, William E. Tapprich

Biology Faculty Publications

The overall purpose of this multifocused study was to explore how participation in genuine mentored scientific research experiences impacts in-service science teachers and the knowledge and skills needed for their own science teaching. The research experiences resulted from a partnership between the University of Nebraska at Omaha and the Omaha Public School District. This Teacher- Researcher Partnership Program facilitated opportunities in inquiry, science content, interaction with laboratory instrumentation and technologies, critical discussion of literature, and dissemination of findings for participating in-service science teacher professional development utilizing an inquiry-based theoretical framework wherein we examined science teacher preparation via inquiry-based methods in ...


Eccentricity Modulation Of Precessional Variation In The Earth’S Climate Response To Astronomical Forcing: A Solution To The 41-Kyr Mystery, Rajarshi Roychowdhury 2018 University of Massachusetts Amherst

Eccentricity Modulation Of Precessional Variation In The Earth’S Climate Response To Astronomical Forcing: A Solution To The 41-Kyr Mystery, Rajarshi Roychowdhury

Doctoral Dissertations

The 41,000-year variability of Earth’s glacial cycles during the late Pliocene-early Pleistocene is usually attributed to variations in Earth’s obliquity (axial tilt). However, a satisfactory explanation for the lack of precessional variation in marine d18O records, a proxy for ocean temperature and ice-volume, remains contested. Here, a physically based climate model is used to show that the climatic effect of precession is muted in global isotope records due to two different mechanisms, with each dominating as a function of eccentricity. At low eccentricities (e0.019), the time-integrated summer insolation and number of positive degree-days impacting ...


Review Of The Ends Of The World: Volcanic Apocalypses, Lethal Oceans, And Our Quest To Understand Earth's Past Mass Extinctions By Peter Brannen, Robert F. Diffendal, Jr. 2018 University of Nebraska - Lincoln

Review Of The Ends Of The World: Volcanic Apocalypses, Lethal Oceans, And Our Quest To Understand Earth's Past Mass Extinctions By Peter Brannen, Robert F. Diffendal, Jr.

Robert F. Diffendal, Jr., Publications

In his new best-selling book, Peter Brannen, award-winning science writer, takes you on a fascinating trip through the run-up to the endCretaceous extinction event and the K-Pg (Cretaceous/ Paleogene) boundary, formerly called the K -T (Cretaceous/Tertiary) boundary. ... Brannen interviewed many scientists who studied these events and went on field trips with them to major Cretaceous sites and to those where earlier and later extinction events happened. He presents clear explanations of what is known and not known about all of these events in a largely error-free book. Brannen details the other four big extinction events in geologic history: the ...


An Overview Of Anorthosite-Bearing Layered Intrusions In The Archaean Craton Of Southern West Greenland And The Superior Province Of Canada: Implications For Archaean Tectonics And The Origin Of Megacrystic Plagioclase, Ali Polat, Fred J. Longstaffe, Robert Frei 2018 University of Windsor

An Overview Of Anorthosite-Bearing Layered Intrusions In The Archaean Craton Of Southern West Greenland And The Superior Province Of Canada: Implications For Archaean Tectonics And The Origin Of Megacrystic Plagioclase, Ali Polat, Fred J. Longstaffe, Robert Frei

Earth Sciences Publications

Anorthosite-bearing layered intrusions are unique to the Archaean rock record and are abundant in the Archaean craton of southern West Greenland and the Superior Province of Canada. These layered intrusions consist mainly of ultramafic rocks, gabbros, leucogabbros and anorthosites, and typically contain high-Ca (>An70) megacrystic (2–30 cm in diameter) plagioclase in anorthosite and leucogabbro units. They are spatially and temporally associated with basalt-dominated greenstone belts and are intruded by syn-to post-tectonic granitoid rocks. The layered intrusions, greenstone belts and granitoids all share the geochemical characteristics of Phanerozoic subduction zone magmas, suggesting that they formed mainly in a suprasubduction ...


Petrogenetic And Geodynamic Origin Of The Neoarchean Doré Lake Complex, Abitibi Subprovince, Superior Province, Canada, Ali Polat, Robert Frei, Fred J. Longstaffe, Ryan Woods 2018 University of Windsor

Petrogenetic And Geodynamic Origin Of The Neoarchean Doré Lake Complex, Abitibi Subprovince, Superior Province, Canada, Ali Polat, Robert Frei, Fred J. Longstaffe, Ryan Woods

Earth Sciences Publications

The Neoarchean (ca. 2728 Ma) anorthosite-bearing Doré Lake Complex in the northeastern Abitibi subprovince, Quebec, was emplaced into an association of intra-oceanic tholeiitic basalts and gabbros known as the Obatogamau Formation. The Obatogamau Formation constitutes the lower part of the Roy Group, which is composed of two cycles of tholeiitic-to-calc-alkaline volcanic and volcaniclastic rocks, siliciclastic and chemical sedimentary rocks, and layered mafic-to-ultramafic sills. In this study, we report major and trace element results, and Nd, Sr, Pb and O isotope data for anorthosites, leucogabbros, gabbros and mafic dykes from the Doré Lake Complex and spatially associated basalts and gabbros of ...


Petrology And Geochemistry Of The Tasse Mantle Xenoliths Of The Canadian Cordillera: A Record Of Archean To Quaternary Mantle Growth, Metasomatism, Removal, And Melting, Ali Polat, Robert Frei, Fred J. Longstaffe, Derek J. Thorkelson, Eyal Friedman 2018 University of Windsor

Petrology And Geochemistry Of The Tasse Mantle Xenoliths Of The Canadian Cordillera: A Record Of Archean To Quaternary Mantle Growth, Metasomatism, Removal, And Melting, Ali Polat, Robert Frei, Fred J. Longstaffe, Derek J. Thorkelson, Eyal Friedman

Earth Sciences Publications

Mantle xenoliths hosted by the Quaternary Tasse alkaline basalts in the Canadian Cordillera, southeastern British Columbia, are mostly spinel lherzolite originating from subcontinental lithospheric mantle. The xenoliths contain abundant feldspar veins, melt pockets and spongy clinopyroxene, recording extensive alkaline metasomatism and partial melting. Feldspar occurs as veins and interstitial crystal in melt pockets. Melt pockets occur mainly at triple junctions, along grain boundaries, and consist mainly of olivine, cpx, opx and spinel surrounded by interstitial feldspar. The Nd, Sr and Pb isotopic compositions of the xenoliths indicate that their sources are characterized by variable mixtures of depleted MORB mantle and ...


Continued Monitoring Of The Effects Of Two Dam Removals On The Middle Cuyahoga River Summit County, Ohio, Connor Estes 2018 The University of Akron

Continued Monitoring Of The Effects Of Two Dam Removals On The Middle Cuyahoga River Summit County, Ohio, Connor Estes

Honors Research Projects

In order to improve water quality of the middle Cuyahoga River, the Munroe Falls and Lefever Dams were removed in 2005, and 2013, respectively. These dam removals have provided an opportunity to quantify how rivers respond to dam removal. This thesis research extends eleven years of river morphology monitoring by measuring channel sedimentologic properties of sediment samples as well as geomorphic transects in 2016 and determined the volume of impoundment sediment prior to the removal of the Munroe Falls Dam.

In the three years following the removal of the Munroe Falls Dam, flow energy increased and the sediment in the ...


Fight And Air Exposure Times Of Caught And Released Salmonids From The South Fork Snake River, Curtis J. Roth, Daniel J. Schill, Michael C. Quist 2018 University of Idaho

Fight And Air Exposure Times Of Caught And Released Salmonids From The South Fork Snake River, Curtis J. Roth, Daniel J. Schill, Michael C. Quist

USGS Staff -- Published Research

Catch-and-release regulations are among the most common types of fishing regulations. In recent years, concerns have arisen regarding the exposure of fish to air during catch-and-release angling. The purpose of our study was to quantify the length of time angled fish were exposed to air by anglers in a typical catch-and-release fishery and relate it to the lengths of time reported to produce negative effects. In total, 312 individual anglers were observed on the South Fork Snake River, Idaho, from May through August 2016. Fight time varied from 1.1 s to 230.0 s, and average fight time was ...


Winter Rain Versus Snow In Headwater Catchments: Responses Of An Unconfined Pumice Aquifer, South-Central Oregon, Usa, Michael L. Cummings, David A. Eibert 2018 Portland State University

Winter Rain Versus Snow In Headwater Catchments: Responses Of An Unconfined Pumice Aquifer, South-Central Oregon, Usa, Michael L. Cummings, David A. Eibert

Geology Faculty Publications and Presentations

Winter precipitation in two headwaters catchments (elevation ~1600 m) in the rain shadow of the Cascades volcanic arc in south-central Oregon normally falls as snow. However, in water year 2015, winter precipitation fell mainly as rain. An eight year study of the unconfined pumice aquifer allowed inter-annual comparison of groundwater recharge during the freshet and discharge during the growing season. During these water years precipitation ranged from 67% (WY2014) to 132% (WY2017) of the 30 year average, and included the rain dominated winter of WY2015 when precipitation during the water year was 98% of the 30 year average. Change in ...


Geology Of The Purgatory Saddle 7.5 Minute Quadrangle, And Gravity And Magnetic Analysis Of Accreted Terrane Boundary, Western Idaho, Sourav Krishna Nandi 2018 Missouri State University

Geology Of The Purgatory Saddle 7.5 Minute Quadrangle, And Gravity And Magnetic Analysis Of Accreted Terrane Boundary, Western Idaho, Sourav Krishna Nandi

MSU Graduate Theses

Western Idaho (USA) contains deformation associated with the Mesozoic accretion of volcanic island arc terranes of the Blue Mountains Province to Laurentia. The near vertical boundary between the accretionary orogeny and Precambrian North America is represented by the transpressional western Idaho shear zone, which lies east of metamorphic rocks in the Salmon River suture zone. The Blue Mountains Province in western Idaho contains four accreted crustal blocks: the Wallowa, Olds Ferry, Baker, and Izee terranes. The purpose of this study is to understand the structural relationship of the pre-accretionary, syn-accretionary and post-accretionary tectonic features along the accreted terrane boundary in ...


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