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Conduction Plus Convection Heat Flow Modeling For The Linga Complex, Peruvian Coastal Batholith, Luciano Uriel González Olivares 2017 Loma Linda University

Conduction Plus Convection Heat Flow Modeling For The Linga Complex, Peruvian Coastal Batholith, Luciano Uriel González Olivares

Loma Linda University Electronic Theses, Dissertations & Projects

Factors affecting the thermal evolution of the Linga magmatic intrusion in the Ica-Pisco area of the Peruvian Coastal Batholith were studied using field work, petrography, geochemistry data, and computer modeling. Field work and petrography involved collecting samples for geochemical analysis and documenting widespread propylitic and potassic hydrothermal alteration. Major element geochemistry was used to estimate rock density, viscosity, liquidus temperature, and water content. The δ18O values of seven fresh samples showed a slightly increasing west-east and old-young trend of approximately 7-8‰, indicating an increasing crustal component. The δ18O and δD values for eleven altered samples indicated that alteration came mostly ...


Collaborative Research: Facet: Quantifying The Topographic Response To Tectonic Processes In Southern Taiwan, Tammy M. Rittenour 2017 Utah State University

Collaborative Research: Facet: Quantifying The Topographic Response To Tectonic Processes In Southern Taiwan, Tammy M. Rittenour

Funded Research Records

No abstract provided.


Excess Silica In Omphacite And The Formation Of Free Silica In Eclogite, H. W. Day, Sean R. Mulcahy 2017 Western Washington University

Excess Silica In Omphacite And The Formation Of Free Silica In Eclogite, H. W. Day, Sean R. Mulcahy

Sean Mulcahy

Silica lamellae in eclogitic clinopyroxene are widely interpreted as evidence of exsolution during decompression of eclogite. However, mechanisms other than exsolution might produce free silica, and the possible mechanisms depend in part on the nature and definition of excess silica. ‘Excess’ silica may occur in both stoichiometric and non-stoichiometric pyroxene. Although the issue has been debated, we show that all common definitions of excess silica in non-stoichiometric clinopyroxene are internally consistent, interchangeable, and therefore equivalent. The excess silica content of pyroxene is easily illustrated in a three-component, condensed composition space and may be plotted directly from a structural formula unit ...


Anthropogenic Infilling Of A Bermudian Sinkhole And Its Impact On Sedimentation And Benthic Foraminifera In The Adjacent Anchialine Cave Environment, Jacquelyn N. Cresswell, Peter J. van Hengstum, Thomas M. Iliffe, Bruce E. Williams, Gil Nolan 2017 Texas A&M University at Galveston

Anthropogenic Infilling Of A Bermudian Sinkhole And Its Impact On Sedimentation And Benthic Foraminifera In The Adjacent Anchialine Cave Environment, Jacquelyn N. Cresswell, Peter J. Van Hengstum, Thomas M. Iliffe, Bruce E. Williams, Gil Nolan

International Journal of Speleology

In the mid-20th century, an inland brackish pond from Bermuda, known as Eve’s Pond, was filled with marine sediment from an adjacent coastal lagoon. At this time, an eyewitness reported “…sediment billowing out of the Green Bay Cave for days…”, which is a marine-dominated anchialine cave located proximal to the former location of Eve’s Pond (~200 m). The purpose of this study was to evaluate the potential impact of this infilling event on cave sedimentation and benthic meiofaunal communities, as proxied by the unicellular protists foraminifera that remain preserved in the sediment record. Eight sediment cores were ...


Holdrege: Nebraska's State Soil, University of Nebraska - Lincoln 2017 University of Nebraska - Lincoln

Holdrege: Nebraska's State Soil, University Of Nebraska - Lincoln

Conservation and Survey Division

No abstract provided.


Holdrege Nebraska State Soil, Nebraska Society of Professional Soil Scientists 2017 Nebraska Society of Professional Soil Scientists

Holdrege Nebraska State Soil, Nebraska Society Of Professional Soil Scientists

Conservation and Survey Division

No abstract provided.


Unlocking The Secrets Of Al-Tobermorite In Roman Seawater Concrete, Marie D. Jackson, Sejung R. Chae, Sean R. Mulcahy, Cagla Meral, Rae Taylor, Penghui Li, Abdul-Hamid Emwas, Juhyuk Moon, Seyoon Yoon, Gabriele Vola, Hans-Rudolf Wenk, Paulo J.M. Monteiro 2017 Western Washington University

Unlocking The Secrets Of Al-Tobermorite In Roman Seawater Concrete, Marie D. Jackson, Sejung R. Chae, Sean R. Mulcahy, Cagla Meral, Rae Taylor, Penghui Li, Abdul-Hamid Emwas, Juhyuk Moon, Seyoon Yoon, Gabriele Vola, Hans-Rudolf Wenk, Paulo J.M. Monteiro

Sean Mulcahy

Ancient Roman syntheses of Al-tobermorite in a 2000-year-old concrete block submerged in the Bay of Pozzuoli (Baianus Sinus), near Naples, have unique aluminum-rich and silica-poor compositions relative to hydrothermal geological occurrences. In relict lime clasts, the crystals have calcium contents that are similar to ideal tobermorite, 33 to 35 wt%, but the low-silica contents, 39 to 40 wt%, reflect Al3+ substitution for Si4+ in Q2 (1Al), Q3 (1Al), and Q3 (2 Al) tetrahedral chain and branching sites. The Al-tobermorite has a double silicate chain structure with long chain lengths in the b [020] crystallographic direction, and wide interlayer spacing, 11 ...


Crustal Shortening, Exhumation, And Strain Localization In A Collisonal Orogen: The Bajo Pequeno Shear Zone, Sierra De Pie De Palo, Argentina, Joshua M. Garber, Sarah M. Roeske, Jessica Warren, Sean R. Mulcahy, William C. McClelland, Lauren J. Austin, Paul R. Renne, Graciela I. Vujovich 2017 Western Washington University

Crustal Shortening, Exhumation, And Strain Localization In A Collisonal Orogen: The Bajo Pequeno Shear Zone, Sierra De Pie De Palo, Argentina, Joshua M. Garber, Sarah M. Roeske, Jessica Warren, Sean R. Mulcahy, William C. Mcclelland, Lauren J. Austin, Paul R. Renne, Graciela I. Vujovich

Sean Mulcahy

The Bajo Pequeño Shear Zone (BPSZ) is a lower-crustal shear zone that records shortening and exhumation associated with the establishment of a new plate boundary, and its placement in a regional structural context suggests that local- to regional-scale strain localization occurred with progressive deformation. A kilometer-scale field and analytical cross section through the ~80 m thick BPSZ and its adjacent rocks indicates an early Devonian (405–400 Ma) phase of deformation on the western margin of Gondwanan continental crust. The earliest stages of the BPSZ, recorded by metamorphic and microstructural data, involved thrusting of a hotter orthogneiss over a relatively ...


Structural Evolution Of A Composite Middle To Lower Crustal Section: The Sierra De Pie De Palo, Northwest Argentina, Sean R. Mulcahy, S. M. Roeske, W. C. McClelland, F. Jourdan, A. Iriondo, P. R. Renne, J. D. Vervoort, G. I. Vujovich 2017 Western Washington University

Structural Evolution Of A Composite Middle To Lower Crustal Section: The Sierra De Pie De Palo, Northwest Argentina, Sean R. Mulcahy, S. M. Roeske, W. C. Mcclelland, F. Jourdan, A. Iriondo, P. R. Renne, J. D. Vervoort, G. I. Vujovich

Sean Mulcahy

The Sierra de Pie de Palo of northwest Argentina preserves middle to lower crustal metamorphic rocks that were penetratively deformed during Ordovician accretion of the Precordillera terrane to the Gondwana margin. New structural, petrologic, and geochronologic data from a 40 km structural transect reveals that the Sierra de Pie de Palo preserves a middle to lower crustal ductile thrust complex consisting of individual structural units and not an intact ophiolite and cover sequence. Top-to-the-west thrusting occurred intermittently on discrete ductile shear zones from ∼515 to ∼417 Ma and generally propagated toward the foreland with progressive deformation. Ordovician crustal shortening and ...


Melt Inclusion Evidence For Magma Evolution At Mutnovsky Volcano, Kamchatka, K. Robertson, A. Simon, T. Pettke, Sean R. Mulcahy, E. Smith, O. Selyangin, A. Kiryukhin, J. D. Walker 2017 Western Washington University

Melt Inclusion Evidence For Magma Evolution At Mutnovsky Volcano, Kamchatka, K. Robertson, A. Simon, T. Pettke, Sean R. Mulcahy, E. Smith, O. Selyangin, A. Kiryukhin, J. D. Walker

Sean Mulcahy

Mutnovsky Volcano, located in Kamchatka, Russia, is a young volcano that has formed a series of four overlapping stratocones over its approximately 80 ka history. Erupted products at Mutnovsky range in composition from basalts to dacites; basalts are the most common. In this study, melt inclusions from representative samples of all erupted compositions from all four eruptive centers were analyzed to investigate the causes of the compositional heterogeneity, melt evolution, and pre-eruptive magma dynamics. Melt inclusions from Mutnovsky were sampled in olivine, plagioclase, orthopyroxene, and clinopyroxene. The melt inclusion data represent a wide range of melt compositions, from basalt through ...


Multiple Migmatite Events And Cooling From Granulite Facies Metamorphism Within The Famatina Arc Margin Of Northwest Argentina, Sean R. Mulcahy, Sarah M. Roeske, William C. McClelland, Joshua R. Ellis, Fred Jourdan, Paul R. Renne, Jeffrey D. Vervoort, Graciela I. Vujovich 2017 Western Washington University

Multiple Migmatite Events And Cooling From Granulite Facies Metamorphism Within The Famatina Arc Margin Of Northwest Argentina, Sean R. Mulcahy, Sarah M. Roeske, William C. Mcclelland, Joshua R. Ellis, Fred Jourdan, Paul R. Renne, Jeffrey D. Vervoort, Graciela I. Vujovich

Sean Mulcahy

The Famatina margin records an orogenic cycle of convergence, metamorphism, magmatism, and extension related to the accretion of the allochthonous Precordillera terrane. New structural, petrologic, and geochronologic data from the Loma de Las Chacras region demonstrate two distinct episodes of lower crustal migmatization. The first event preserves a counterclockwise pressure-temperature path in kyanite-K-feldspar pelitic migmatites that resulted in lower crustal migmatization via muscovite dehydration melting at ∼12 kbar and 868°C at 461 ±1.7 Ma. The shape of the pressure temperature path and timing of metamorphism are similar to those of regional midcrustal granulites and suggest pervasive Ordovician migmatization ...


Phillipsite And Al-Tobermorite Mineral Cements Produced Through Low-Temperature Water-Rock Reactions In Roman Marine Concrete, Sean R. Mulcahy, Marie D. Jackson, Heng Chen, Yao Li, Piergiulio Cappelletti, Hans-Rudolf Wenk 2017 Western Washington University

Phillipsite And Al-Tobermorite Mineral Cements Produced Through Low-Temperature Water-Rock Reactions In Roman Marine Concrete, Sean R. Mulcahy, Marie D. Jackson, Heng Chen, Yao Li, Piergiulio Cappelletti, Hans-Rudolf Wenk

Sean Mulcahy

Pozzolanic reaction of volcanic ash with hydrated lime is thought to dominate the cementing fabric and durability of 2000-year-old Roman harbor concrete. Pliny the Elder, however, in first century CE emphasized rock-like cementitious processes involving volcanic ash (pulvis) “that as soon as it comes into contact with the waves of the sea and is submerged becomes a single stone mass (fierem unum lapidem), impregnable to the waves and every day stronger” (Naturalis Historia 35.166). Pozzolanic crystallization of Al-tobermorite, a rare, hydrothermal, calcium-silicate-hydrate mineral with cation exchange capabilities, has been previously recognized in relict lime clasts of the concrete. Synchrotron-based ...


Chemical And Pb Isotope Composition Of Phenocrysts From Bentonites Constrains The Chronostratigraphy Around The Cretaceous-Paleogene Boundary In The Hell Creek Region, Montana, Ryan B. Ickert, Sean R. Mulcahy, Courtney J. Sprain, Jessica F. Banaszak, Paul R. Renne 2017 Western Washington University

Chemical And Pb Isotope Composition Of Phenocrysts From Bentonites Constrains The Chronostratigraphy Around The Cretaceous-Paleogene Boundary In The Hell Creek Region, Montana, Ryan B. Ickert, Sean R. Mulcahy, Courtney J. Sprain, Jessica F. Banaszak, Paul R. Renne

Sean Mulcahy

An excellent record of environmental and paleobiological change around the CretaceousPaleogene boundary is preserved in the Hell Creek and Fort Union Formations in the western Williston Basin of northeastern Montana. These records are present in fluvial deposits whose lateral discontinuity hampers long-distance correlation. Geochronology has been focused on bentonite beds that are often present in lignites. To better identify unique bentonites for correlation across the region, the chemical and Pb isotopic composition of feldspar and titanite has been measured on 46 samples. Many of these samples have been dated by 40Ar/39Ar. The combination of chemical and isotopic compositions of ...


Estimation Of Total Dissolved Solid In Groundwater Using Multiple Linear Regression Analysis Around Igando Dumpsites In Lagos, South-West, Nigeria, Anthony A. Ameloko, Elijah A. Ayolabi 2017 Convenant University, Ota, Nigeria

Estimation Of Total Dissolved Solid In Groundwater Using Multiple Linear Regression Analysis Around Igando Dumpsites In Lagos, South-West, Nigeria, Anthony A. Ameloko, Elijah A. Ayolabi

Confluence Journal of Environmental Studies (CJES), Kogi State University, Nigeria

This study presents a multiple linear regression (MLR) TDS model that relates the TDS data obtained from groundwater samples to the geophysical data obtained from Electromagnetic (EM) data, as an alternative approach to mapping and monitoring the impact of TDS in groundwater. The predictive power of the developed MLR TDS model was appraised to determine the feasibility of using the TDS model to predict groundwater TDS around the study area. Although, the accuracy of the developed TDS model is site specific, the EM data around the area can be applied to the model to determine TDS concentration in groundwater, thus ...


In Situ Dating Of Multiple Events In Granulite-Facies Rocks Of The Larsemann Hills, Prydz Bay, East Antarctica Using Electron Microprobe Analysis Of Monazite, Steven K. Spreitzer 2017 University of Maine

In Situ Dating Of Multiple Events In Granulite-Facies Rocks Of The Larsemann Hills, Prydz Bay, East Antarctica Using Electron Microprobe Analysis Of Monazite, Steven K. Spreitzer

Electronic Theses and Dissertations

The metamorphic rocks exposed along the southeast coast of Prydz Bay were affected by several metamorphic and plutonic events associated with collision in the Neoproterozoic and Cambrian. Critical units exposed in the Larsemann Hills and nearby ice-free areas include (1) basement Søstrene Orthogneiss, (2) cover sequence Brattstrand Paragneiss and (3) anatectic pegmatites intrusive into the Brattstrand Paragneiss. Zircon U-Pb data from previous studies yielded a maximum depositional age of 1023 ± 19 Ma for the Brattstrand Paragneiss, but only approximate ca. 900 Ma to ca. 1000 Ma and ca. 530 Ma ages for two metamorphic events. In order to constrain the ...


Sulfur-Based Speleogenesis In The Cumberland Plateau, Usa, Lee J. Florea 2017 Ball State University

Sulfur-Based Speleogenesis In The Cumberland Plateau, Usa, Lee J. Florea

Lee J Florea, PhD, P.G.

No abstract provided.


Soputan Volcano, Indonesia: Petrological Systematics Of Volatiles And Magmas And Their Bearing On Explosive Eruptions Of A Basalt Volcano, Syegi Lenarahmi Kunrat 2017 Portland State University

Soputan Volcano, Indonesia: Petrological Systematics Of Volatiles And Magmas And Their Bearing On Explosive Eruptions Of A Basalt Volcano, Syegi Lenarahmi Kunrat

Dissertations and Theses

Soputan volcano is one of the few basaltic volcanoes among 127 active volcanoes in Indonesia. It is part of the Sempu-Soputan volcanic complex located south of Tondano Caldera, North Sulawesi and commonly produces both explosive eruptions with VEI 2-3 and effusive lava dome and flow eruptions. Over the last two decades, Soputan had thirteen eruptions, the most recent in 2016. Most eruptions started explosively, followed by dome growth and in some cases pyroclastic flows. Our study focuses on understanding the magmatic system of Soputan and what processes are responsible for its highly explosive eruptions, which are typically uncommon for a ...


The Dynamic Relationship Between The Bear River, Quaternary Basaltic Center, Normal Faults, And The Resulting Rearrangement Of Rivers In The Northeast Edge Of The Great Basin, Southeast Idaho, Brady Utley 2017 Utah State University

The Dynamic Relationship Between The Bear River, Quaternary Basaltic Center, Normal Faults, And The Resulting Rearrangement Of Rivers In The Northeast Edge Of The Great Basin, Southeast Idaho, Brady Utley

All Graduate Plan B and other Reports

The objective of this research project in Gem Valley graben, southeast Idaho is to identify the location, age and history of the Quaternary diversion of the Bear River into paleo-Lake Thatcher, and then into the Lake Bonneville basin from the Columbia River basin. Mapping, geochemical analysis, cross-cutting relationships, and five new age determinations, together with prior published research, shed new light on the complex history of interaction between the volcanic rocks, rivers, lakes, and faults in Gem Valley. Research goals were to test the hypothesis that local faulting and volcanism drove the diversion of the Bear River and controlled the ...


On The Pursuit Of Relevance In Standards-Based Curriculum Development: The Ccny Approach, Angelo Lampousis 2017 CUNY City College

On The Pursuit Of Relevance In Standards-Based Curriculum Development: The Ccny Approach, Angelo Lampousis

Publications and Research

The Society for Standards Professionals (SES) has a significant history of documenting the use of standards in research and academia. For instance, during the 62nd Annual SES Conference in 2013 in Savannah, Georgia, the author participated in such a session highlighting examples of relationships between academic institutions, government, and standards developing organizations. In this article, we attempt to capture the current advances made from similar relationships specific to our home institution, the City College of New York (CCNY) of the City University of New York (CUNY.) These advances have become possible through a grant issued under the Standards Services Curricula ...


Near Surface Geophysics For Lithostratigraphic Interpretation At Pedro, Benton County, Arkansas, Matthew David Ruggeri 2017 University of Arkansas, Fayetteville

Near Surface Geophysics For Lithostratigraphic Interpretation At Pedro, Benton County, Arkansas, Matthew David Ruggeri

Theses and Dissertations

The roadcut on highway 412 near Pedro, Benton County, Arkansas (MArkUP site L15), has been of geological interest since its excavation in the 1980s. The roadcut is located within the Springfield Plateau and displays formations of Lower Mississippian age. The roadcut contains three mound-like features believed to be olistoliths. This thesis research work adds geophysical evidence to the geological exposure at the site. The purpose of this research is to answer the question of whether near surface seismic methods can be used to extend information at the Pedro outcrop below the ground surface. Specifically, can the top of the Middle ...


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