Earth Sciences Commons^™

Partitioning Of Rare Earth And High Field Strength Elements Between Titanite And Phonolitic Liquid, Paul H. Olin, John A. Wolff

Geosciences Faculty Publications and Presentations

We present the results of a LA–ICPMS study of titanites and associated glasses from the mixed-magma phonolitic Fasnia Member of the Diego Hernández Formation, Tenerife, Canary Islands. We employ a method of identifying equilibrium mineral–melt pairs from natural samples using REE contents and a linear form of the lattice strain model equation (Blundy and Wood, 1994), where the Young's modulus (E_M) for the 7-fold coordinated site is an output variable. For felsic magmas that contain crystals potentially derived from a variety of environments within the system, this approach is more rigorous than the use of solely textural criteria …

Near-Surface Imaging Of A Hydrogeothermal System At Mount Princeton, Colorado Using 3d Seismic, Self-Potential, And Dc Resistivity Data, Andrew P. Lamb, Lee M. Liberty, Kasper Van Wijk, André Revil, Chuck Diggins

CGISS Publications and Presentations

The Upper Arkansas Valley in the Rocky Mountains of central Colorado is the northernmost extensional basin of the Rio Grande Rift(Figure 1). The valley is a half graben bordered to the east and west by the Mosquito and Sawatch ranges,respectively. The Sawatch Range is home to the Collegiate Peaks,which include some of the highest summits in the Rocky Mountains. Some Collegiate Peaks over 4250 m (14,000 ft) from north to south include Mount Harvard, Mount Yale, Mount Princeton,and Mount Antero. The Sawatch range-front normal fault strikes north-northwest along the eastern margin of the Collegiate Peaks and is characterized by a …

Hurricane Disturbance And Recovery Of Energy Balance, Co2 Fluxes And Canopy Structure In A Mangrove Forest Of The Florida Everglades, Jordan G. Barr, Vic Engel, Thomas J. Smith, José D. Fuentes

United States Geological Survey: Staff Publications

Eddy covariance (EC) estimates of carbon dioxide (CO2) fluxes and energy balance are examined to investigate the functional responses of a mature mangrove forest to a disturbance generated by Hurricane Wilma on October 24, 2005 in the Florida Everglades. At the EC site, high winds from the hurricane caused nearly 100% defoliation in the upper canopy and widespread tree mortality. Soil temperatures down to −50 cm increased, and air temperature lapse rates within the forest canopy switched from statically stable to statically unstable conditions following the disturbance. Unstable conditions allowed more efficient transport of water vapor and CO₂ from …

The Effect Of Dissolved Humic Acids On Aluminosilicate Formation And Associated Carbon Sequestration, Ashaki A. Rouff, Brian L. Phillips, Stacey G. Cochiara, Kathryn L. Nagy

Publications and Research

Allophane and imogolite neogenesis in soils may occur in the presence of organic matter. To understand this process under conditions relevant to soils, the influence of dissolved organic carbon (DOC) as humic acid (HA), on aluminosilicate formation was studied at 25◦C, pH 6, and low-DOC concentrations. For solutions with initial Al/Si ratios of 1–2.1, and 0–6mg/L DOC, precipitates recovered after 20h had Al/Si ratios of 2.2–2.7. The formation of allophane, imogolite-like material, and aluminosilicate gel was confirmed by XRD, FTIR, and NMR. The effect of DOC was to produce a small, but systematic increase in imogolite-like Si in the precipitate, …

Three-Dimensional Hydrostratigraphy Of The Sprague, Nebraska Area: Results From Helicopter Electromagnetic (Hem) Mapping For The Eastern Nebraska Water Resources Assessment (Enwra), Dana Divine, Jesse T. Korus

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

First Year Morphological Evolution Of An Artificial Berm At Fort Myers Beach, Florida, Katherine Brutsche, Ping Wang

Geology Faculty Publications

This Coastal and Hydraulics Engineering Technical Note (CHETN) documents the sediment characteristics and first year morphological evolution of an artificial berm placed just offshore in Fort Myers Beach, Florida, based on a series of field data collection periods during the first year after the berm construction.

Seismic Reflection Study Of The East Potrillo Fault, Southwestern Dona Ana County, New Mexico, Shane Alan Carley

Open Access Theses & Dissertations

The East Potrillo Mountains are located just north of the U.S.-Mexico border in southwestern Dona Ana County, New Mexico. Laramide and Rio Grande rift deformation has formed low-angle and high-angle Tertiary normal faults that are exposed in the area. Along the east flank of the range is the East Potrillo Fault identified on the surface as a north-striking scarp. Fault scarps associated with the East Potrillo Fault have been dated using slope degradation models and they range between 56 ka and 377 ka in age. Offset of geomorphic surfaces interpreted to be tectonic terraces records at least four earthquakes over …

Dynamic Earthquake Triggering In The Continental U.S., Ibrahim Cerda

Open Access Theses & Dissertations

Seismological studies have classified the changes in field stress required to trigger remote earthquakes into two basic types: static and dynamic triggering. Static triggering mainly originates from geological faults already present in certain tectonic environments and they could be originated due to continental crust, subduction zones or even from a highly seismicity zone. Dynamic triggering occurs when an event (earthquake) has been induced by the passing of seismic waves from a large main shock located at least two or more fault lengths from the epicenter of the main shock. This study investigates details of dynamic triggering not seen in previous …

Evaluating Hydrocarbon Source Rock For Unconventional Shale Oil Play From Seismic And Well Log Data; Kingak Shale, North Slope, Alaska, Sarah Elisabeth Leedberg

Open Access Theses & Dissertations

It has been proposed that Acoustic impedance (AI) responses can be used to estimate total organic carbon (TOC) within thick, clay rich shale. The purpose of this work is to evaluate the effectiveness of the AI inversion technique, and establish a methodology that can be applied to other basins. The Kingak Formation (lower Jurassic to early Cretaceous), located on the North Slope of Alaska, has been extensively evaluated for its unconventional potential. The Kingak is shale and is known to have greater than 30 percent clay. Because clay has ductile properties it makes it difficult to stimulate a well through …

Constraints On The Structure Of The Border Ranges Fault System, South-Central Alaska From Integrated 3d Inversion Of Gravity/Magnetic Data, Niti Mankhemthong

Open Access Theses & Dissertations

I use updated gravity data, available aeromagnetic data, and other geophysical information as constraints to develop 2D and 3D structural models of density and magnetic susceptibility to better locate and determine the shape of the Border Ranges fault system (BRFS), the Border Range ultramafic and mafic assemblages and other forearc-arc boundary structures in south-central Alaska, that have previously been studied in only limited detail. There are three geophysical research projects that form the chapters of the dissertation. First, I estimated near-surface density variations in the central Kenai Peninsula based on the adaptation of the Nettleton (1939)-Parasnis (1952) method using Tarantola …

Numerical Modeling Of Tectonics And Fault Activity Of Icy Satellites, John Olgin

Open Access Theses & Dissertations

Enceladus, one of the satellites of Saturn, exhibits evidence of recent fault activity, which may be due to gravitational fluctuations, or tidal stresses, generated by its orbit around Saturn. Recent Cassini spacecraft observations of Enceladus reveal water-ice plume activity at the south polar region, originating from locations that correlate with four geologically young, linear fracture-like features, named the "tiger stripes". It is the goal of this investigation to determine the ideal geophysical and geological factors (e.g., fault depths, frictional coefficients, ice layer thickness, ocean layer thickness, tidal stress sources) that support fault activity on Enceladus. The core of this work …

Constrained Optimization Schemes For Geophysical Inversion Of Seismic Data, Uram Anibal Sosa Aguirre

Open Access Theses & Dissertations

Many experimental techniques in geophysics advance the understanding of Earth processes by estimating and interpreting Earth structure (e.g., velocity and/or density structure). These techniques use dierent types of geophysical data which can be collected and analyzed separately, sometimes resulting in inconsistent models of the Earth depending on data quality, methods and assumptions made. This dissertation presents two approaches for geophysical inversion of seismic data based on constrained optimization. In one approach we expand a one dimensional (1-D) joint inversion least-squares (LSQ) algorithm by introducing a constrained optimization methodology. Then we use the 1-D inversion results to produce 3-D Earth velocity …

Isotope Geochemistry And Geochronology Of Lavas From The Line Islands Chain, Central Pacific Basin: Insight Into The Origin Of The Line Islands, Lauren Storm

Open Access Theses & Dissertations

Geochemical compositions of melts produced in the Earth's mantle provide key data for understanding Earth's internal structure. Particularly, the compositions of unusually large outpourings of basaltic lavas in large igneous provinces involve substantial source volumes, thereby contributing to our understanding of mantle structure and dynamics. Although the origin of such lavas remains enigmatic, geochemically they may originate from Earth's oldest and deepest mantle reservoir, transported by a mantle plume or by entrainment in passive upwelling beneath a fast spreading center. The Pacific Ocean basin hosts several large igneous provinces that formed near a triple junction of three oceanic plates, and …

Implications Of Decade Time Scale Arctic Plant Community Change On Ecosystem Function, Mark Jason Lara

Open Access Theses & Dissertations

Almost half the global soil organic carbon pool is found in northern high latitudes. The majority of this soil carbon is stored in a greenhouse inert state within permafrost. As pronounced warming of high northern latitudes ensues, there is a strong likelihood that this substantial soil organic carbon pool will be mobilized to the atmosphere where it is likely to positively enhance greenhouse warming. Modeling studies suggest this positive feedback could alter future climate states of the Arctic and the globe, and affect how humans may need to adapt to climate change. Accordingly, understanding the patterns and controls and the …

Variability In The Mass Flux Of The Ross Sea Ice Streams, Antarctica, Over The Last Millennium, Ginny Catania, Christina L. Hulbe, Howard Conway, Ted A. Scambos, C. F. Raymond

Geology Faculty Publications and Presentations

We synthesize previously published remote-sensing observations, radar data and model output to obtain a ~1000 year ice flow history for the Siple Coast ice-stream system in West Antarctica to investigate the timing and magnitude of changes in mass flux. The synthesized history shows significant short-term variability in ice-stream shear margin and grounding line position due to internal variability of the coupled system. The chronology highlights the interplay between adjacent ice streams, which implies that the behavior of any individual ice stream should not be examined in isolation. Furthermore, individual events cannot be fully interpreted without an understanding of the broad-scale, …

Late Pleistocene And Holocene Aged Glacial And Climatic Reconstructions In The Goat Rocks Wilderness, Washington, United States, Joshua Andrews Heard

Dissertations and Theses

Eight glaciers, covering an area of 1.63 km2, reside on the northern and northeastern slopes of the Goat Rocks tallest peaks in the Cascades of central Washington. At least three glacial stands occurred downstream from these glaciers. Closest to modern glacier termini are Little Ice Age (LIA) moraines that were deposited between 1870 and 1899 AD, according to the lichenometric analysis. They are characterized by sharp, minimally eroded crests, little to no soil cover, and minimal vegetation cover. Glacier reconstructions indicate that LIA glaciers covered 8.29 km2, 76% more area than modern ice coverage. The average LIA equilibrium line altitude …

New Methods For The Discovery And Characterization Of Lunar Lava Tubes Using Lunar Reconnaissance Orbiter Data, Jonathan Arthur Meyer

Open Access Theses & Dissertations

Lava tubes have the potential to serve as a sustainable solution to long-term lunar habitation by providing protection from radiation and micrometeorite bombardment while potentially providing resources in the form of trapped water ice. They also pose compelling science targets in their own right. While the potential benefits of utilizing lunar lava tubes is clear, their discovery is less straightforward. Formation processes for lava tubes do not always result in a surface expression, making their discovery using remotely sensed imagery difficult. Furthermore, there is the potential for lava tubes to be covered by secondary lava flows, impact ejecta, or other …

Vertical Deformation Along The San Andreas Fault, Garrett Thornton

Open Access Theses & Dissertations

There have been numerous M 6+ earthquakes along the San Andreas Fault System (SAFS) (Schwartz et al., 1984) (Figure. 1.1) in the historical past. These rupture events have created millions of dollars worth of damage, and have been responsible for multiple lives lost. An improved understanding of the motions and crustal characteristics along the SAFS can lead to better hazard mitigation (Bakun et al., 2005). Horizontal crustal motions of the SAFS have been widely studied and applied to seismic hazard models (WGCEP, 2007), however vertical motions are not often utilized due to their complicated origin and sometimes large uncertainties. This …

Impervious Surface Area Change In Arkansas From 2001 To 2006, D. E. Long Ii, R. C. Weih Jr.

Journal of the Arkansas Academy of Science

Impervious Surface Area (ISA) is a measurement used to determine stream quality as well as urban sprawl. ISA was calculated as part of the National Land Cover Dataset (NLCD) using Landsat imagery by the Multi-Resolution Land Characteristics Consortium (MRLC) in both 2001 and 2006. ISA for each of the 75 counties in Arkansas was taken from the NLCD for both 2001 and 2006. Using the ISA data, percent imperviousness was determined for each county in each time period as well as the difference between the two periods. These data were also compared to census projections for the two time periods …

Surface Lineaments And Lithofacies Distribution Of The Tyler Formation In Southwestern North Dakota, Nicolas Beltran Guerrero

Earth & Environmental Sciences Theses - Archive

The purpose of this study is to investigate whether a correlation exists between surface lineaments and lithofacies distribution of the Pennsylvanian Tyler Formation in the southwest portion of North Dakota of the Williston Basin. If a cost-effective technique to locate preserved fluvial sandstone bodies can be developed, the Tyler Formation has the potential to be a productive hydrocarbon exploration target. Many intercratonic sedimentary basins, such as the Williston Basin, exhibit nearly orthogonal surface lineaments. In the case of the Cooper Basin in Australia, lineament analysis helped locate areas where Proterozoic rocks are fractured and filled with quartz veins containing precious …

Al-In-Hornblende Thermobarometry And Sr-Nd-O-Pb Isotopic Compositions Of The Early Miocene Alaçam Granite In Nw Anatolia (Turkey), Altuğ Hasözbek, Burhan Erdoğan, Muharrem Satir, Wolfgang Siebel, Erhan Akay, Güllü Deni̇z Doğan, Heinrich Taubald

Turkish Journal of Earth Sciences

During and after the closure of the Neo-Tethyan Ocean and progressive collision of the Tauride-Anatolide Platform with the Sakarya Continent, widespread magmatism occurred in NW Anatolia. This magmatism is manifested in a NW-trending belt along the northern border of the Menderes Massif. Due to the complex geodynamic setting of this region, the exact emplacement depth of the granitoids is still a matter of debate. Here we present Al-in-hornblende barometrical data and Sr-Nd-Pb isotope compositions of the Early Miocene Alaçam granite. The results imply a shallow emplacement depth of this granite (4.7±1.6 km) in contrast to previous studies which suggested emplacement …

Stable Isotope Composition Of Hydrothermally Altered Rocks And Hydrothermal Minerals At The Los Azufres Geothermal Field, Mexico, Ignacio S Torres Alvarado, Muharrem Satir, Daniel Perez Zarate, Peter Birkle

Turkish Journal of Earth Sciences

The Los Azufres geothermal field is the second most important geothermal field for electricity production in Mexico, with a total installed capacity of 188 MW. Hydrothermal alteration studies have been an important tool for geothermal exploration and development of the field, but little attention has been given to the geochemical and isotopic characterization of hydrothermal minerals. \delta^1^8O, \delta^2H, and \delta^1^3C systematics at Los Azufres geothermal field were investigated using whole rock samples, as well as hydrothermal minerals separates, obtained from different depths in the wells Az-26 and Az-52. Most \delta^1^8O values reproduce well the present in-situ field temperatures and isotopic …

Kinematics And Basin Formation Along The Ezinepazar-Sungurlu Fault Zone, Ne Anatolia, Turkey, Mehmet Korhan Erturaç, Okan Tüysüz

Turkish Journal of Earth Sciences

The Ezinepazar-Sungurlu Fault (EzSF) is a major offshoot of the dextral North Anatolian Fault (NAF) zone, which bifurcates from the main fault strand around the Niksar pull-apart basin (37°E) and strikes through the Central Anatolian Block for 200 km to the west (34°E). The easternmost segment of the EzSF, the Ezinepazar Fault (EzF), which ruptured during the 1939 Erzincan earthquake (Mw= 7.8), has a very remarkable expression as a single-strand fault. Micromammal dating of young sediments along this segment indicate that the EzF was initiated during the Middle Pleistocene (0.7-1 Ma) and propagated westward accumulating 6.5±0.5 km maximum morphological offset. …

Palaeozoic Formations From Dobrogea And Pre-Dobrogea – An Overview, Antoneta Seghedi

Turkish Journal of Earth Sciences

No abstract provided.

Stratigraphy And Some Structural Features Of The İstanbul Paleozoic, Necdet Özgül

Turkish Journal of Earth Sciences

Palaeozoic rocks crop out across large areas in the İstanbul region. The Palaeozoic sequence starts with the Lower Ordovician fluviatile and lacustrine deposits (Kocatöngel and Kurtköy formations). The area was transgressed by the sea during the Late Ordovician-Early Silurian, represented by the feldspathic quartzwacke and quartz-arenites of the Kınalıada and Aydos formations. The basin became progressively deeper and more stable during the Silurian and Devonian. In this period, micaceous siltstones and sandstones of the Yayalar Formation (Upper Ordovician (?)-Lower Silurian), shelf-type carbonates of the Pelitli Formation (Lower Silurian-Lower Devonian), fossil-rich micaceous shales with rare limestone intercalations representing a low-energy open …

Model Ordinance For Development On Karst In Kentucky: Guidance For Construction On Karst Terrain And The Reduction Of Property Damage And Threat To Human Health Resulting From Karst Geologic Hazard, James C. Currens

Information Circular--KGS

I have dealt with hundreds of incidents of karst-related geohazards; some have caused major damage to buildings and infrastructure. Although cases are largely limited to the ground surface being made unusable, a significant number of structures are damaged by karst flooding or cover collapse each year, which is devastating to families who have lost their homes. Most of these events should never have happened, because the karst hazard could have been avoided by selecting a better building site or designing the building to withstand the damage from the hazard. Furthermore, most of the planning authorities I have had experience with …

Mines And Minerals Of The Western Kentucky Fluorspar District, Warren H. Anderson, Thomas N. Sparks

Map and Chart--KGS

This map shows all the known and identified mines, mineral prospects, and igneous intrusions (dikes or sills) in the Western Kentucky Fluorspar District, compiled from thousands of maps and files, creating an up-to-date, comprehensive catalog for the district. The district has been extensively mined for more than 120 years and was once the largest producer of fluorspar (fluorite) in the United States.

Millions of tons of vein ore minerals (fluorite, zinc, lead, and barite) has been produced from these mines, and substantial reserves still remain. New mining and exploration activity has renewed interest in the district, and the industry will …

Geodynamic Constraints On The Flow Of Samoan-Plume Mantle Into The Northern Lau Basin, Nathan Katsiaficas

Honors Theses

The northernmost portion of the Lau basin, South Pacific, features numerous geochemical and geophysical anomalies. These include: (1) a strong latitudinal gradient in the trace element and isotopic (Sr-Nd-Pb) enrichment of basalts erupted along the various back-arc spreading centers (BASCs) within the basin, (2) high 3He/4He (up to 28 times RA, where RA, the ratio in Earth's atmosphere, is 1.4 x 10-6) in basalts erupted along some portions of the BASCs (e.g., Rochambeau Bank), and (3) the presence of trench-parallel shear-wave splitting near the Tonga arc. The occurrence of these anomalies has been attributed to the southward flow of mantle …

Examination Of Spatial Variations In Recrystallization Mechanisms In Quartz, Emma N. Beck

Honors Theses

S-C mylonites form as a result of non-coaxial deformation in ductile shear zones. Planes of weakness develop and delineate two domains, the S and the C Each of these domains accommodates variable amounts of strain. Sample WMSZ-188 exhibits subgrain rotation (SGR) recrystallization in the C domains, and grain boundary migration (GBM) recrystallization in the S domains. This partitioning of recrystallization mechanisms indicates either: (1) strain-rate partitioning during a single deformation event; or (2) a second, lower-temperature deformation event that over-printed the C domains. This study tests these two hypotheses. Optical and EBSD analyses were used to look for evidence of …

Assessing Satellite-Based Rainfall Estimates In Semiarid Watersheds Using The Usda-Ars Walnut Gulch Gauge Network And Trmm Pr, Eyal Amitai, Carl L. Unkrich, David C. Goodrich, Emad Habib, Bryson Thill

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The rain gauge network associated with the Walnut Gulch Experimental Watershed (WGEW) in southeastern Arizona provides a unique opportunity for direct comparisons of in situ measurements and satellite-based instantaneous rain rate estimates like those from the Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR). The WGEW network is the densest rain gauge network in the PR coverage area for watersheds greater than 10 km(2). It consists of 88 weighing rain gauges within a 149-km(2) area. On average, approximately 10 gauges can be found in each PR field of view (similar to 5-km diameter). All gauges are very well synchronized with …