Senior Theses (SES)

Pressure-Temperature Conditions of Granulite Formation in Rogaland, SW Norway

2013-06-04T14:01:42Z

Pressure-Temperature Conditions of Granulite Formation in Rogaland, SW Norway Edwards, Katrina The geology of SW Norway is dominated by high-grade amphibolite to granulite facies gneisses with associated migmatites and anorthosite-magerite complexes. Previous work suggests that metamorphism consisted of two high temperature events at 1.45 Ga (MI) and 1.0 Ga (M2), followed by regional cooling and formation of retrograde assemblages (M3). Partial reequilibration of certain mineral phases has led to some uncertainty about the pressures of metamorphism and whether the retrograde assemblages represent a discrete metamorphic event. Pressure and temperature conditions of the M2 metamorphism of gneisses located near the osumilite-in isograd were constrained using gt-opx, opx-bt, cord-btgt, and gt-sill-qt-plag equilibria. Core compositions were used for all ferromagnesium phases to avoid the effects of Fe-Mg exchange during cooling. Results suggest that peak metamorphism occurred at pressures of 5-6 kb and temperatures of 71O-800°C. Rim temperatures and pressures were estimated at 490-550°C and 4-5 kb, suggesting retrograde metamorphism, and possibly implying isobaric cooling.

The evaluation of slope failure in Baldwin Hills, Los Angles County, California

2013-06-04T14:01:33Z

The evaluation of slope failure in Baldwin Hills, Los Angles County, California Spensiero, Scott D. The Baldwin Hills area has suffered widespread damage from slope failures in the past. The problems of slope instability are particularly severe in the area for two reasons. First, the development of the hills was prior to the enactment of grading codes by local government. Second, the terrain consisted of steep slopes underlain by soft sedimentary rocks. Slope failures in the Baldwin Hills have occurred in the form of landslides and erosion, associated with unusually heavy winter rainfall. The landslides are in form of mudslides with soil slips and mudflows. These failures are derived partly from the mantle of soil and slope wash that overlies the bedrock of clay-rich material on natural slopes. Slopes underlain by Culver sand are particularly vulnerable to erosion. In the most densely developed areas of Baldwin Hills that have suffered slope damage in the past, 345 (about 21%) of 1668 residential properties are known by the California Division of Mines and Geology (CDMG) to have been damaged by slope failure. Additionally, about 93% of the 1668 residential lots apparently have potential for at least minor damage from slope failure in the future, unless measures are taken to stabilize slopes that include or endanger these properties (Weber, 1982).

Late Pleistocene history and stratigraphy of Niagara Falls

2013-06-04T14:01:26Z

Late Pleistocene history and stratigraphy of Niagara Falls Kennedy, Raymond Niagara Falls owes its origin to Pleistocene glaciation. As the glaciers retreated northward a sequence of glacial lakes and outlets developed. With the opening of the Mohawk outlet to the Hudson, waters from glacial lake Algonquin subsided to below the Niagara Escarpment. This led to the formation of the Niagara River and gorge. The volume of water discharging through the river has varied considerably, ranging from 15% to 110% of present flow, with the opening or closing of alternate drainage outlets. The falls has receded 11.2 km up river from its point of origin, Lewiston N. Y.. The retreat of the falls is the result of the interaction of water with the undelying sedimentary rock. In the past the falls retreated at a rate of 0.9 - 1.8 meters per- year. Today, water is being diverted away from the falls for hydroelectric power and the rate of retreat has slowed to 0.3 - O.6 meters per year.

An investigation into the geomorphology of the Ohio Caverns

2013-06-04T14:01:19Z

An investigation into the geomorphology of the Ohio Caverns Berls, Norman J. The Ohio Caverns are located in north west Champaign County about four miles east of the town of West Liberty, Ohio on Route 245. The caverns are perhaps the most extensive in the entire state. The caverns wind through the rock in a particular configuration. This paper attempts to establish a relationship between this configuration and the joint patterns in the area. The caverns also have a particular internal configuration. This paper also attempts demonstrate how this internal configuration is a function of various geologic processes. It becomes involved in a consideration of the origin of the debris in the cave and the effects the debris had on the formation of the cave. It considers the effects the water table had on the cave as the water table retreated. This report also deals with present processes going on in the cave and attempts to relate them to the local geology.

A proposed stratigraphic package for filling a mid-Proterozoic rift basin under the Bellefontaine Outlier area, Ohio, and the consequences of the rift on the formation of the Outlier

2013-06-04T14:01:13Z

A proposed stratigraphic package for filling a mid-Proterozoic rift basin under the Bellefontaine Outlier area, Ohio, and the consequences of the rift on the formation of the Outlier Loveday, David C. The discovery of a mid-Proterozoic rift basin in the crystalline basement rocks under the Bellefontaine Outlier area, Ohio has had a number of consequences on our understanding of Precambrian tectonics and stratigraphy of western Ohio and the northcentral North American midcontinent. In this study, a new stratigraphic package has been proposed to fill the ancient rift basin and a geolbgical history of the area from the mid-Proterozoic to the Devonian, has been synthesized to study the consequences of this deep basement feature through time. Three new proposed rift basin-filling volcanic and sedimentary units encode the development, maturation, and termination of the rift. A fourth proposed sedimentary unit, lying above the basin-filling sequence, documents the initial changes of the region to a massive foreland basin in front of newly developed Grenvillian thrust sheets during the late-Proterozoic. The lower contact of the Middle Run Formation has also been extended to a much greater depth overlying the fourth proposed unit and represents welldeveloped foreland basin sediments. Another goal of this study considers tectonic events from the mid-Proterozoic initiation of rifting through the Devonian Acadian Orogeny, to explain the development and incomplete Paleozoic stratigraphy of the Bellefontaine Outlier. Compressive forces associated with the Grenville Orogeny may have propagated the rift-defining fault complexes up through the overlying late-Proterozoic strata and imposed significant structural weaknesses that could be exploited by the compressive forces of the Devonian Acadian Orogeny. During the Acadian, the Outlier block may have been exhumed by the reactivated faults and the Devonian Delaware Limestone and Olentangy Shale units, not present within the Outlier block, may have been syntectonically deposited in flanking basins during the exhumation.

A STUDY OF HIGH WALL DETERIORATION

2013-06-04T14:01:07Z

A STUDY OF HIGH WALL DETERIORATION Parsons, Kenneth

Interpretation of the Fresh Water/Brine Interface of the Devonian/Silurian Carbonates of Central Ohio

2013-06-04T14:00:59Z

Interpretation of the Fresh Water/Brine Interface of the Devonian/Silurian Carbonates of Central Ohio Compton II, Steven C. This thesis was conducted to determine the relation between the brine horizon and the beds of the Devonian/Silurian carbonate units known by the drillers' name, Big Lime. The relation can take three forms: A) the brine horizon dips parallel to its parent bed, B) the brine horizon dips at a steeper angle than its parent bed, or C) the brine horizon dips at a shallower angle than its parent bed. It is important to know this relation so that an approximate depth to brine can be determined during the drilling of oil and gas wells, which contain brine as a by-product, in addition to determining the depth at which brine can be found for the injection of waste brine. Data as to the depth to the "First Brine" of the Big Lime and the top of the Big Lime was determined using oil and gas "header cards" archived in the Geologic Records Section of the Ohio Department of Natural Resources Division of Geological Survey. The data were imported into SURFER for Windows and contour maps were made of the top of the Big Lime and the elevation of the First Brine Horizon. These maps were compared and the relation between the brine horizon and the top of the Big Lime was determined. This relation agrees with Scenario B above. Utilization of these findings makes it possible to determine the relative placement of the Big Lime's brine horizon compared to its upper surface. This information will aid drillers and environmental scientists in the determination of where brine will be encountered and where brine can be found for the disposal of petroleum-industry brines by injection.

SUBSURFACE AND PETROLEUM GEOLOGY OF ASHTABULA COUNTY, OHIO

2013-06-04T14:00:49Z

SUBSURFACE AND PETROLEUM GEOLOGY OF ASHTABULA COUNTY, OHIO Shoots, James W.

The Regional Oceanography of the Kara Sea and Examination of core C-93/134 from the East Novaya Zemlya Trough, Russia

2013-06-04T14:00:38Z

The Regional Oceanography of the Kara Sea and Examination of core C-93/134 from the East Novaya Zemlya Trough, Russia Walker, Laura J. The Kara Sea is a shallow epicontinental sea located in the Russian Arctic. Dominant currents of the Kara Sea change seasonally; dense bottom waters in the winter and surface riverine controlled currents in summer. North Atlantic derived intermediate waters enter the Kara Sea through deep troughs. The East Novaya Zemlya Trough runs roughly parallel and east of the Novaya Zemlya archipelago, the location of core C-93/134. Magnetic susceptibility, bulk densities, color, continuous laminations, and sand, silt and clay percentages reflect the homogeneity of depositional environment of unit 1A. Unit 1B is interpreted as a turbidite or mass slumping event due to the anomalous percentage sand and biota. Fecal pellets, present in the upper 40 cm of the core, result in the possible misrepresentation of sand percentages for the intervals sampled in the upper 40 cm. Sedimentation in the East Novaya Zemlya Trough is dominated by pelagic input and at selected times gravity driven processes.

Origin of Enigmatic Hills in the Ross Sea, Antarctica

2013-06-04T14:00:24Z

Origin of Enigmatic Hills in the Ross Sea, Antarctica Magee, William R.

Application of LAS files in a Reservoir Characterization study to investigate Geologic Sequestration and Enhanced Oil Recovery in the East Canton oil field, Ohio

2013-06-03T19:31:26Z

Application of LAS files in a Reservoir Characterization study to investigate Geologic Sequestration and Enhanced Oil Recovery in the East Canton oil field, Ohio Cronin, Mickey With growing need for energy resources and mitigation of carbon dioxide emissions, there is increased interest in enhanced oil recovery (EOR) as a potential solution. Many oil fields with declining pressure and production still have the potential to produce millions of barrels of oil. Understanding oil-reservoir geology is important in determining how the formation will react to and sequester injected CO₂ as a method of EOR and mitigation. In this correlation study of reservoir stratigraphy within the producing interval of the East Canton field, geophysical wireline well logs and LAS file applications were used. This method allows for the gathering of large amounts of publically-available subsurface data to use in geologic interpretations. Many stratigraphic cross sections were created using LAS (Log ASCII Standard) applications; two representative cross sections are applied here. Through these cross sections, subtle and apparent changes in lithologic character, depositional environment, and continuity were observed for the producing interval, which is a series of complex sandstone lenses known as the “Clinton” sandstones. These cross sections and interpretations will add to an ongoing investigation by the Ohio Division of Geological Survey leading to the potential recovery of valuable energy resources along with the mitigation of an anthropogenic greenhouse gas.

A Reinterpretation of Bedrock Contours Using Glacial Deposits

2013-06-04T14:00:13Z

A Reinterpretation of Bedrock Contours Using Glacial Deposits Reese, Jeff L.

Spatial Distribution of Visible Desert Salts in the McMurdo Region, Antarctica

2013-05-02T06:22:45Z

Spatial Distribution of Visible Desert Salts in the McMurdo Region, Antarctica Bisson, Kelsey Desert environments are distinctive in that they are the only landscapes that accumulate salts in measureable quantities. The McMurdo Dry Valleys in Antarctica are classified as a polar desert, as they maintain very low relative humidities by the sweeping katabatic winds that descend upon the continent and produce very little (<3cm annual) precipitation. Salts are abundant and a notable feature of the soils. Surficial salt crusts were sampled in the top 2 cm of soils in the Dry Valleys and on Ross Island in the area surrounding McMurdo Station to determine their source for formation, as well as to identify spatial trends in the data. Unlike previous salt studies, this one focuses on visible, surface salt crusts with soil depth possibly through sequential evaporation of groundwater as it moves to the surface. Using structural and textural criteria, 2 types of salt crusts may be distinguished: (1) widespread surface crusts with little structure; and (2) thicker salt crusts with amorphous shape that form near boulders. Subsurface soluble salts and stratified salt crusts were not sampled in this study. Chemical analysis of the major ions indicates conflicting trends in major marine ions, suggesting that the marine influence in salt formation is not as significant as was hypothesized. Sodium is the major cation, averaging 70-90% of all major cations measured. Chloride and sulfate are the major anions in the salts, with chloride being the most abundant (<70%) in Taylor Valley surface salts, though it is less abundant at McMurdo station. Higher elevation coastal areas have abundant calcium, up to 60 meq/kg sediment sampled. Statistical analysis reveals that salt chemistries are not significantly different with respect to their sampling elevation, location, and proximity to a water source. Qualitative comparisons of salt chemistries show an influence of formation “type,” as salts accumulated under large particle faces are chemically distinct from those that were found alongside streambeds.

Analysis of Potential Methane Hydrate Accumulations in a Block 857 Alaminos Canyon Well Site, Gulf of Mexico

2013-05-02T06:22:48Z

Analysis of Potential Methane Hydrate Accumulations in a Block 857 Alaminos Canyon Well Site, Gulf of Mexico Crock, Abigail The Gulf of Mexico has long been an area of extensive scientific study as a basin of geologic interest. The Gulf is in close proximity to the U.S. and the extensive gas hydrate that has been found during drilling operations there make it an attractive option for a potential continuous energy source long after gas and oil supplies have diminished. In this study, a well in the Alaminos Canyon Block 857 (API no. 608054002300), Gulf of Mexico, was examined using logging data, core records, and heatflow maps to determine if methane hydrate was potentially present in this area. Resistivity, API gravity, gamma ray, hydrocarbon fluorescence and bottom-simulating reflectors were all compared to seek markers that may suggest hydrate accumulations. This well, in an interval from 10240-10725 feet below the rig floor, shows the most promising indications of hydrate. Saturation values along this length averaged fifty-nine percent which was calculated using Archie’s equation. After further analysis, gas condensate presence seemed more likely than hydrate but the saturation values calculated are still applicable. Future work should focus on repeating this process across other wells in Alaminos Canyon to determine the volume of methane hydrate that may exist, remaining careful to distinguish between hydrate and condensate concentrations. Ultimately, a distinct consensus on the amount of gas hydrate in the Gulf of Mexico will clarify the economic practicality of hydrates as an energy source.

Carbon isotope variations on ancient carbonate platforms: The roles of organic carbon burial and sea level

2013-05-01T06:22:02Z

Carbon isotope variations on ancient carbonate platforms: The roles of organic carbon burial and sea level Trigg, Cody Positive delta 13C trends in ancient carbonate rocks are commonly interpreted to reflect increases in the burial of organic carbon in sediments. An alternative model to explain positive delta 13C trends in shelf carbonate rocks is related to mixing with open ocean water during transgression that floods the carbonate platform. Rock samples from two age-correlated, stratigraphic sections from the Arbuckle Mountains, Oklahoma and Clear Spring, Maryland of Middle to Upper Ordovician age were measured and sampled for delta 13C and delta 18O. The delta 13C curves reveal 3-4 per mil positive shifts in the upper Darriwilian to lower Sandbian stages (C. sweeti to gerdae conodont zones). Lithological analysis indicates transgressive events (shallow to deeper marine) associated with the positive delta 13C shifts in the Appalachian foreland basin but indicates a transgressive-regressive sequence in the upper portions of the Arbuckle Mountains. Plots of delta 13C versus delta 18O reveal minimal covariance, potentially invalidating diagenetic explanations for the trend. Because delta 13C does not show an obvious correlation with water depth or diagenesis, these results suggest that the positive delta 13C positive trends of both sections may be closely related to global changes in organic carbon burial.

Crust-Magma Interactions of the Hengill Volcanic Complex in Iceland

2013-05-01T06:21:46Z

Crust-Magma Interactions of the Hengill Volcanic Complex in Iceland Gress, Nathan This research has determined the relationship between magma evolution and pressures of partial crystallization at the Hengill volcanic complex in Iceland. Petrologic studies determined pressure, therefore depth, of partial crystallization to complement seismic studies which have difficulty providing details of crustal structure at depths greater than 9km due to resolution. This research has explored implications of petrologic results to provide information about the magma plumbing system beneath Hengill. Hengill is located in SW Iceland in the western rift zone and is the site of a mid ocean ridge intersecting with a transform margin marked by the South Iceland Seismic Zone. Previous work by Tronnes, and by Gurenko and Sobolev, provide analyses of basaltic glasses representing quenched magmas. Tronnes divided the analyses into 4 groups, based on chemical composition and occurrence of various clinopyroxene phenocrysts and xenocrysts. Two of the groups contain clinopyroxene xenocrysts that show clear evidence for resorbtion. Gurenko and Sobolev’s study involved glass samples in gabbroic xenoliths with resorbed clinopyroxene at the contact between the xenocryts and magma. Variations in chemical composition shown by these analyses were used to study the evolution of Hengill’s magmas and to calculate pressures of partial crystallization. Nearly all available glass analyses were used in this study. A small number of samples were filtered out of the data set because they have anomalously high silica contents, anomalous aluminum contents, or anomalous concentrations of other elements (see Kelly and Barton, 2008, for discussion). Plots of oxide concentrations versus MgO indicate samples that contain the resorbed clinopyroxenes do not follow the same trends as the other glass samples. The latter samples are the results of the processes of crystallization and, therefore, the different trends show the effects of crust and magma interacting with each other (clinopyroxene assimilation) in the samples containing resorbed clinopyroxene. Calculated pressures of partial crystallization are used to infer a magma chamber depth of approximately 15km. This is slightly deeper but similar to that of Kelley and Barton’s calculation of 12km and Gurenko and Sobolev’s 10km. Interpretation of these calculations is not straightforward. Resorbed clinopyroxenes and evidence for crustal contamination may lead to anomalous results and skew the pressure data if not taken into account, appearing to generate pressures that can be far lower than the actual conditions that caused their compositions at the time of crystallization.

Nutrient Geochemistry in North Central Ohio Lakes

2013-05-01T06:20:31Z

Nutrient Geochemistry in North Central Ohio Lakes Michalak, John C. Eight lakes in north central Ohio have been sampled to review their nutrient chemistry. Analysis was also done to compare the variation in nutrient concentration at primary locations of recharge and discharge. Five of the lakes have primary inlet and outlet stations which have also been sampled. The three reservoirs only have lake sampling measurements. The samples were collected starting in December of 2010 and continued through September of 2012. The lakes would be classified as small and the largest of them is 1350 acres. All of the water samples collected were run through a Skalar nutrient analyzer and tested for PO43- , NH4- , and NO3-+NO2-. Once the data was compiled, graphs showed all eight lakes/reservoirs with the variations in chemistry of the three nutrients. Based on the average nutrient concentrations of the lakes studied, they are considered to be in poor biological condition. The data also shows that the lakes are acting as a sink for nitrogen based on the variation of inlet and outlet concentrations. Cyanobacteria decomposition was an important factor in the concentration of ammonium concentrations at various locations sampled in the lakes.

Evaluating Anthropogenic Impact on Water Quality of Ohio Rivers Over Time

2013-04-30T06:22:45Z

Evaluating Anthropogenic Impact on Water Quality of Ohio Rivers Over Time Dailey, Kelsey Natural and anthropogenic factors affect the geochemistry of rivers and streams in both rural and urban areas. Much of the impact on fresh water in the U.S. comes from non-point sources, with population and land use playing an important role. Two major anthropogenic inputs to surface waters are chloride and sodium, derived mostly from urban contributions such as road salt. Additionally, nitrate represents another large input, primarily from agricultural sources such as fertilizers. Many water quality studies exist for rivers and streams in parts of the Northeastern U.S., which have yielded increases in chloride concentration over time. Concerns in central Ohio arising from road salt application and storage practices have developed in the past few years, including potential chemical effects on local wildlife in streams and road salt’s role in polluting Ohio drinking water. Historical data on fresh water quality exist for many Ohio rivers but haven’t been further utilized to observe ion concentration trends over past decades. Past data were tabulated from the United States Geological Survey and The Ohio State University School of Earth Sciences to identify long-term trends in ion concentrations in rivers at multiple locations throughout the greater Columbus and central Ohio area. In June 2012 and March 2013, a number of sites were sampled for major ions and nutrients and compared to previous data. Comparing the 2012-2013 samples to those from same sites in the past, identifiable trends showing general increases in ion concentration over time were found in the river locations with complete historical data sets. The time series of some localities are not complete due to many gaps in data collection over the past 40-50 years. Analysis of chloride to bromide mass ratios in the Ohio surface waters revealed that the source of chloride was likely halite, or road salt.

Ocean oxygenation during the Middle Ordovician: links to biodiversification?

2013-04-30T06:22:44Z

Ocean oxygenation during the Middle Ordovician: links to biodiversification? Diamond, Charles During the Ordovician period, biological diversity experienced a threefold increase (Great Ordovician Biodiversification Event). This expansion took place in several steps, with one of the largest pulses of diversification occurring in the Middle Ordovician (Darriwilian). This study presents paired carbon isotope data from carbonate and organic matter from the Antelope Valley Limestone of Meiklejohn Peak, Nevada, a Darriwilian carbonate sequence. A correlation is established between this section and two Estonian drill cores in which the MDICE has been previously reported. This correlation, based on carbon isotope stratigraphy, is supported by paleontological evidence. These data represent the first documentation of the Mid-Darriwilian Carbon Isotope Excursion (MDICE) from western Laurentia. The paired results of this study show a stepwise increase of approximately 3‰ in photosynthetic fractionation through the early stages of the MDICE, consistent with an increase in atmospheric oxygen of up to 18% (i.e. an increase from a starting atmospheric oxygen concentration of 10% to 28%). Increases in atmospheric oxygen are thought to have played a critical role in key evolutionary developments throughout time, such as the rise of animals at the end of the Precambrian and the gigantism seen in arthropods of the Permo-Carboniferous. The timing of the pulse of oxygen observed in the Darriwilian coincides with the timing of rapid biodiversification, suggesting that the two may have been intimately linked.

An Exploratory Study of Ephemeral Snow Cover in the Midwest and the Potential Hydrologic Impacts on the Great Lakes with a Warming Climate

2013-04-30T06:20:01Z

An Exploratory Study of Ephemeral Snow Cover in the Midwest and the Potential Hydrologic Impacts on the Great Lakes with a Warming Climate Rine, Matthew Snow cover in the Midwest is a primary contributor to the hydrologic cycle and has significant surface energy balance, biogeochemical, ecological, and societal impacts. This exploratory study addresses some of these issues and looks at some of the primary drivers that affect a snow cover in the Midwest. Much of this region is dominated by an ephemeral snow cover, so the first issue to be addressed is to define what is meant by ephemeral snow and where exactly it transitions into an all-winter (seasonal) snow cover in the Midwest. An ephemeral snow cover is one that comes and goes throughout the winter months, having no seasonal duration. For example in Columbus, Ohio winter average temperature is 2° Celsius, and snow cover has a typical duration of less than 15 days. How well can average winter temperature be used to predict duration of snow cover throughout the winter months? I found that when comparing snow duration to average winter temperatures it is seen that there is an 11 day increase with each degree Celsius decrease. The third and final issue is a look at how the hydrology of the Great Lakes region will be affected by a temperature increase of 2° Celsius. My research shows that as much as 25 percent of the snow cover in the Great Lakes Basins will shift from a seasonal to an ephemeral snow pack with a 2° increase. There is a transition zone at an average winter air temperature of -4° to -6° Celsius where the seasonal pattern shifts from a seasonal snow cover to more of an ephemeral pattern. If we were to experience a 2° increase, the areas on this border of a seasonal snow cover would inevitably shift from a seasonal to ephemeral snow, and would have 15 to 20 days fewer of snow cover a year. These ‘at risk’ areas would have implications on the Great Lakes if they were to begin to provide runoff throughout the winter as opposed to having a single spring melt event yearly. First place at the 2013 Denman Research Forum

A morphometric and alignment analysis of volcanic seamounts to determine stress directions, northwestern Ross Sea, Antarctica

2013-04-30T06:21:43Z

A morphometric and alignment analysis of volcanic seamounts to determine stress directions, northwestern Ross Sea, Antarctica Rosenbeck, Loren Linear arrangements of monogenetic volcanic vents represent important sources for stress and strain data. These volcanic alignments form in platform volcanic fields due to separated eruptions along the trend of fissures fed by subsurface feeder dikes. Subsurface feeder dikes and their surface volcanic vents form alignments parallel to the maximum horizontal stress direction and perpendicular to the minimum horizontal stress in the upper crust, either due to formation of new, magmatically-induced cracks or by the exploitation of suitably oriented preexisting fractures. This research focuses on mapping volcanic vent alignments of a platform volcanic field on the Ross Sea floor in Antarctica. A new method for systematic mapping of vent alignments and elongate vents using multibeam bathymetry is developed. A morphometric analysis of each volcanic vent was completed to provide constraints for mapping the trend of the underlying fissure. Parameters including the measurement of the axial ratio of vent base shape, standard deviation of orthogonal distances from the best fit line connecting vents, standard angular deviation of the vent long axes from the trend of the best fit line, and the average distance between cones were used to test the reliability of each alignment. Mapped alignments have a dominant NE-SW trend, documenting a regional NW-SE orientation of the minimum horizontal stress. This stress direction is not compatible with the orientation of rift structures in the region, suggesting that this is a younger stress regime.

A Study of the Rose Run Sandstone and its oil and gas potential at the Knox Unconformity in Ohio

2013-04-24T19:36:11Z

A Study of the Rose Run Sandstone and its oil and gas potential at the Knox Unconformity in Ohio Griffith, Michael R.

A Study of the Magma Chamber Depths Along the Reykjanes Ridge

2013-04-01T17:26:35Z

A Study of the Magma Chamber Depths Along the Reykjanes Ridge Strecker, Elise The research conducted determined the depth of the magma chambers along the Reykjanes ridge. The magma that is being ejected from the chambers along the Reykjanes ridge contains elements important to determining the depth of the chambers, such as MgO, Fe2O3, and CaO. These elements are characteristic of certain minerals that crystallize during the cooling of the magma. By determining when and specifically what minerals begin to crystallize it will then be able to be determined at what average depth the chamber is located, along the ridge. This research is being done because there has not been significant research along the Reykjanes ridge. The research was conducted by gathering the data from other papers, and a public database website, it was then placed into an excel spreadsheet and was graphed by using a computer program called CoHort. Once the graphs were created and interpreted, the pressures were calculated using an excel spreadsheet that was created for this specific reason. Looking at the Cohort graphs and interpreting the trends it could be seen at what rate and pressure the specific minerals were crystallizing during the cooling of the magma along the Reykjanes ridge.

Spatial and Temporal Variations of Water Quality in Hellbranch Run: A Historical Perspective

2013-01-01T07:23:01Z

Spatial and Temporal Variations of Water Quality in Hellbranch Run: A Historical Perspective Volk, John M. The Big Darby Creek west of Columbus, Ohio is a National Scenic River and is highly protected by governmental and nongovernmental agencies. A watershed tributary, Hellbranch Run, drains land that has recently seen conversion from agricultural land to urban. Urbanization can degrade streams due to increased impervious surfaces in the watershed which create pulses of sediments and pollutants to flow to streams during storm events. Study objectives are to determine and interpret the temporal and spatial dynamics of major nutrient and total suspended solids concentrations from four sites along Hellbranch Run. Sites represent different land-use catchments and upstream/downstream on the mainstem of the stream. Land-use records from 1992, 2001 and 2006 were used to compare changes in nutrient loads overtime to land-use changes. Bimonthly sampling took place from Nov. 2009 to Nov. 2010. Sampling involves measuring temperature, pH and TDS in situ in the stream. Samples were analyzed for major nutrients, including nitrate+nitrite-N, ammonium, total nitrogen, phosphate and total phosphorus concentrations. Results show total phosphorus having very high concentrations: median 398 ug/L and range (66.8 to 1,773 ug/L), whereas ammonium is closer to an environmentally acceptable level: median 52.8 ug/L, range (11.7 to 1623 ug/L). Additionally, Hamilton Ditch, a headwater draining cultivated crop, tends to have the highest concentrations of all nutrients, whereas the larger urban headwater streamreach showed lower values. Seasonal shifts exhibited a strong control on nitrate with highest values in the winter and lowest in the summer, while phosphorus shows a weaker trend with highest values in the fall. Suspended solids ranges from 4.4-612 with mean 38.5 mg/L and has lower values upstream and highest just downstream of the confluence of the two headwaters. Historical flow, nutrients and TSS data was used to estimate daily loads using the program LOADEST and the resulting time series shows an estimated decrease in nitrate loads over the last 18 years. Knowing the current state of the water quality along Hellbranch Run is important in understanding the effects that local land-use has on it and will aid land management policy-makers.

Pressures and Depths of Crystallization of the FAMOUS Region Magmas

2012-12-14T07:48:38Z

Pressures and Depths of Crystallization of the FAMOUS Region Magmas Bastawros, Mark The FAMOUS region is between the Mid-Atlantic Ridge and the rift valley which is < 3,000-21,000 ±6,000 years old. This study used analyses of basalt glass from the FAMOUS region. The depth of crystallization is calculated from estimated pressures. To do so we filtered the data by removing any glasses with anomalous chemical compositions or samples that had estimated pressures that were obviously incorrect. The results for 65 glasses indicate that FAMOUS region magmas crystallize over a relatively wide range of pressures from 0 - 228.5MPa, corresponding to depths of 0-8.04 km with an average of 1.42km. Information of the depths of chambers and pressures of crystallization is important for understanding magma evolution, magma plumbing systems, and predicting volcanic activity.

Holocene Glacial Variability Recorded in Lake Sediments from Nevado Huaguruncho, Peru

2012-12-13T07:32:02Z

Holocene Glacial Variability Recorded in Lake Sediments from Nevado Huaguruncho, Peru Sedlak, Christopher Glaciers and lakes are recorders of high altitude climate changes, and these archives are important in our understanding of past global changes. This study aims to provide further insight into how temperature and precipitation varied in the past, and combined to drive glacial variability in the tropical Andes of South America. A percussion core was taken in the field at Lake Yanacocha located in the watershed of Nevado Huaguruncho, Peru. Bulk density was measured along the profile of core and the chronology was determined by measuring radiocarbon on macrofossil samples within the sediments. The core geochemistry was analyzed using scanning X-Ray Fluorescence (XRF), Inductively Coupled Plasma Mass Spectrometry (ICP-MS), and coulometry. Changes in clastic sediment concentrations in the Yanacocha sediment core are represented by shifting values of Ti, K, bulk density, organic carbon, and residual flux. High clastic sediment values characterize the early Holocene, followed by low values during most of the early stages of the mid-Holocene, at a time the lake sediments suggest there was a period of more arid conditions. There is a notable increase in clastic sediments starting at the end of the mid-Holocene, and again during the late Holocene. This study, when paired with other similar research, further improves our knowledge of the timing and causes of climate variability in the tropical Andes, and suggests that glaciers during the Holocene advanced at times of both colder and wetter conditions.

Characterization of the Upper Cambrian and Lower Ordovician Formations for CO2 Sequestration, Scioto County, Ohio

2012-08-09T06:27:28Z

Characterization of the Upper Cambrian and Lower Ordovician Formations for CO2 Sequestration, Scioto County, Ohio Hull, Brad Carbon dioxide sequestration into porous rock intervals beneath the Earth’s surface is an emerging technique of reducing the amounts gaseous CO2 emitted by energy production through the burning of coal/peat. Target intervals of rock must have sufficient pore space, permeability, thickness, depth from the surface, and must be located beneath an impermeable geologic seal to serve as a reservoir for the sequestration of supercritical CO2. The Upper Cambrian-Early Ordovician Knox Supergroup including the Copper Ridge Dolomite, Rose Run Sandstone, and Beekmantown Dolomite formations found within the Aristech Well in Scioto County, Ohio may have all the necessary requirements to serve as a viable combination of CO2 reservoir and geologic seal. This research seeks to characterize samples drawn from these formations on the basis of petrography, porosity, pore size and distribution, permeability, bulk mineralogy, and brine chemistry to distinguish suitable sequestration horizons in conjunction with an overlying caprock. Light microscopy, scanning electron microscopy, mercury porosimetry, and x-ray diffraction analyses established a porous and permeable reservoir interval including the upper Copper Ridge and entire Rose Run overlain by the impermeable Beekmantown Dolomite. The Rose Run Sandstone was the most favorable for CO2 storage, while vertical heterogeneity within the Copper Ridge Dolomite limited the reservoir thickness. Porosity measurements for the reservoir were between 3 and 8%, permeability was 16-50 mDarcies, while the caprock porosity was 1% and permeability of 7 mDarcies. Porosity and pore size distribution between and within samples is controlled by mineralogy, mineral nucleation, diagenesis, and heterogeneity. Volumetric estimations show that the Copper Ridge/Rose Run reservoir could hold up to 5.6 million metric tonnes of supercritical CO2 under the most favorable conditions.

Dinosaur Eggshell and Bird Eggshell Comparison using Scanning Electron Microscopy

2012-06-11T12:17:11Z

Dinosaur Eggshell and Bird Eggshell Comparison using Scanning Electron Microscopy Martin, Lee Eggshell fragments from four extant birds and two Cretaceous dinosaurs were studied for their chemical components. Eggs from the birds yielded high C, O, Mg, Al, and Na values. Dinosaur eggs from the Two Medicine Formation of Montana and the Xiaxia Formation of Henan, China, shared high values of Si, Al, O, Ca, Mg, K, and Na. In addition, material from Henan, China, shared high values of Ce and V. Compositional differences between the bird eggs and the dinosaur eggs are attributed largely to diagenetic factors affecting the fossils.

Characterization of the Mt. Simon Sandstone in Southwest Ohio for CO2 Sequestration

2012-06-08T06:17:53Z

Characterization of the Mt. Simon Sandstone in Southwest Ohio for CO2 Sequestration Leeper, Nicholas CO2 sequestration in deep subsurface environments has been proposed as an innovative strategy to lessen the impact of burning fossil fuels on Earth’s atmosphere. In order for CO2 sequestration to be effective, the target formation must have sufficient porosity, permeability, depth and thickness to store CO2. The Mt. Simon Sandstone, a Cambrian arenite to arkosic sandstone in western Ohio may provide appropriate physical and mineralogical properties for effective CO2 sequestration. The goal of this research is to evaluate the Mt. Simon sandstone’s volumetric capacities including connected porosity, pore size and pore volume, as well as to determine mineralogy and digenetic processes, to assess the formation’s suitability for CO2 sequestration. Samples and measurements were performed on the ODGS 2627 Warren well, and on the ODGS 2843 Armco well to evaluate spatial continuity and vertical heterogeneity. Porosity and pore size distribution measurements were determined using mercury porosimetry and BET gas sorption. Grain size measurements were determined through the use of light microscopy. Results show a porosity range of 1-25%, a connected pore size range of 5-1612 nm, and a decrease in grain size from the base of the Mt. Simon Sandstone through the overlying Eau Claire Formation. Variations in porosity and pore size show that the formation is heterogeneous, changing substantially on a macro scale. Changes in grain size are representative of a transgressive depositional system. Mineralogical characterization of the target Mt. Simon Sandstone and surrounding formations used powder X-ray diffraction, SEM, and polarized light microscopy to show lithologic variations from arenite to feldspathic sandstone, with cementation that included quartz, illite, chlorite, carbonate, iron and titanium oxides, and iron sulfides. Results show heterogeneity in each formation that occurs laterally. Comparison of lithology and pore space reveals that mineralogy and diagenetic processes are the main factors controlling available pore space, and that clean quartz arenite provide the greatest porosity. CO2 storage calculations show that the Warren well location could hold up to 61.0 million metric tons, however this would not provide enough storage space to sustain a long term coal fire power plant.

Intraplate Seismicity: Implications and Uses of the Ohio Seismic Network

2012-12-28T23:59:30Z

Intraplate Seismicity: Implications and Uses of the Ohio Seismic Network Phillips, Zachary R. The Ohio Seismic Network (OhioSeis) was founded in 1999; this study was conducted to look in to the possibilities of working with the available data from their online database and to familiarize others with the procedures behind finding magnitudes of earthquakes based on a seismogram. To study these possibilities, the data, the seismogram viewer and magnitude calculation program will be tested for accuracy. To educate those unfamiliar with the Ohio Seismic Network, a walkthrough of the stations will be given and data will be analyzed as an example to help better understand the process that goes with analyzing a seismic record. The goal at the end of the walkthrough is for anyone to be able to step in and calculate the magnitude of any given event available on the database and understand what that calculation means. To test the data of the database, seismograph data will be collected and analyzed using the same methods used by the volunteers who work for Ohioseis. The results of this test will display any possible problems with the data, acquisition process, data manipulation, or calculation process. Data suggest that there are problems within the processes of calculating magnitudes of earthquakes in Ohio, and that more investigation is necessary in order to overcome these inconsistencies.

Grimsvotn: Pressure of Crystallization and Magma Chamber Depth

2012-06-07T06:18:00Z

Grimsvotn: Pressure of Crystallization and Magma Chamber Depth Rawson, Kyle Volcanoes in Iceland pose an enormous threat to not only the environment but a large portion of the population due to the sheer number and potential destruction that lies under each one. Grimsvötn, being the most frequently erupting volcano in Iceland, is a great locality to develop more of an understanding into how these volcanoes actually work and what we can do to better prepare ourselves for future events. Basaltic glass samples were taken and analyzed using various methods in order to determine partial pressures of crystallization. From this we can deduce magma chamber depth and interpret through various petrological methods, a possible system which lies beneath the volcanoes. As a result of completing this procedure we have concluded that the data are best explained by the presence of a complex plumbing system, consisting of both a shallow and deep chamber, and plexus of small chambers at various depths, or a deep chamber linked to the surface by dikes. Similar models have been proposed for the plumbing systems beneath other volcanoes in Iceland.

Total Organic Carbon Variability in The Utica Shale of Northwest Ohio

2012-12-28T23:39:20Z

Total Organic Carbon Variability in The Utica Shale of Northwest Ohio Cox, Kyle The Utica Shale is an Ordovician age rock unit found throughout most of Ohio and much of the Northeastern United States. Recently, the Utica’s potential as a source and reservoir for hydrocarbons (oil and natural gas) has become an important topic in Ohio. If the Utica contains large amounts producible of oil and gas, the economic impact on the state could be very significant. Due to its hydrocarbon generating potential, there is a great amount of ongoing research focusing on the Utica. Most of this investigation targets the Utica in Eastern Ohio since geologic factors in the area (history of oil and gas production, the unit resides within a window of ideal formation depth below the surface) and preliminary explorations indicate a high likelihood that producible amounts of hydrocarbon reside in the formation in that part of the state. Similar factors (though not as ideal) may exist in the Northwestern portion of the state, however little research has considered this area. The purpose of this study was to investigate the hydrocarbon potential of the Utica Shale in Northwestern Ohio by measuring TOC values of rock samples from the area, and investigating how these values vary throughout the area. Total Organic Carbon, more commonly referred to as TOC, is one important indicator of a geologic units potential as a source rock. It is a measurement of the concentration of organic material in a rock which is necessary for the generation of hydrocarbons. TOC measurements from the Utica in Northwest Ohio were obtained by acidifying rock samples from the Utica in the study area to remove Inorganic Carbon from the samples followed by combusting them in an Elemental Analyzer which measured the remaining, and thus organic, Carbon. 34 samples were obtained from 16 wells in 10 counties of Northwest Ohio. Results showed limited hydrocarbon potential for the area. The average TOC was 1.38% and the 34 samples ranged from 0.73 to 2.75% TOC with the majority of samples falling between 1 and 2%. No strong trends in the variability of the TOC by location were identified. Future research following the same methodology with a larger sample area or a closer-spaced sample frequency across the study area could reveal trends that were too broad or narrow to be identified by measuring the sampled wells.

Volcanism of the Canary Islands: An overview with petrologic characteristics

2012-06-06T06:16:02Z

Volcanism of the Canary Islands: An overview with petrologic characteristics Modlich, Mitchell The study of the volcanic activity that surrounds and builds ocean islands may yield evidence of thermal and chemical anomalies within Earth’s mantle. Although not the most typical or famous of ocean islands, the Canaries archipelago is of importance in the understanding of ocean island volcanism and mantle dynamics. The Canary Islands lie in the Atlantic Ocean off the Northwest coast of Africa. The geologic setting is that of an archipelago within a slow-moving tectonic plate close to a passive continental margin. It has been suggested that the islands are the products of “hot spot” volcanism, i.e. the result of a mantle plume. However, more recently it was proposed that the origin of the Canary Islands is likely the result of a sheet-like mantle thermal anomaly aided by regional tectonics and structural geology. Existing geochemical data were analyzed for differences in major oxides among the seven islands and numerous volcanoes of the Canaries. Interpretation of the data yields conclusions about the composition of the mantle source region and the processes of magma evolution. Comparisons are drawn to existing intra-plate oceanic volcanism such as the Hawaiian Islands. This project aims to achieve a better understanding of the dynamics of the Canary Islands and their origin.

Glacial Deposits of South-Central Fayette County, Ohio

2012-05-01T14:45:39Z

Glacial Deposits of South-Central Fayette County, Ohio Johnson II, Harold Everett Glacial deposits are common and varied across Ohio. These deposits chiefly include lodgment till, ablation till, and outwash. All of these sediment types can be found by drilling into the subsurface of Fayette County, Ohio. The study region, located in the south-central portion of Fayette County (along Miami Trace Road), was examined for glacial deposits using data collected from water well logs and drilling reports. Additional data sources including topographic maps, open-file bedrock geology maps, and open-file bedrock topography maps were used and a cross-section constructed. Variations in bedrock topography record effects of the Teays Stage drainage and the Deep Stage drainage, which in turn influences the thickness of drift. The overlying glacial sediments consistently show an upward pattern of hardpan, sand, and oxidized clay loam in both the ground moraine and end moraine landforms. This sequence is interpreted to record a glacial advance, an increase in meltwater, and the deposition of the uppermost layer either from supraglacial/englacial debris or by a second advance of the Wisconsinan ice sheet.

Controls on soil development and carbon storage on the high-standing island of Taiwan

2012-04-27T06:18:34Z

Controls on soil development and carbon storage on the high-standing island of Taiwan Von Bargen, Justin Studies on weathering rates of high standing islands (HSIs) have shown high observed rates of chemical weathering. However, attempts to correlate these rates to sources have often suffered due to a lack of sufficient soil geochemical data. Furthermore, few studies have attempted to determine a relationship between soil organic carbon content, storage, and seq uestration with uplift and erosion rates. Taiwan sits on top of a highly active convergent plate boundary between the Eurasian and Philippine Sea Plate, which results in intense uplift, creating the orogenic mountains that make up the island. The plate margin has uplift rates >10 mm/yr and contains erosional features dominated by mass-wasting. The island also contains three of the nine rivers in the world which have average sediment concentrations >10 g/l (Milliman and Syvitski, 1992). This study determined organic carbon, inorganic carbon, and a relative amount of weathering in soils between three locations on Taiwan with different lithology and seismicity and with various rates of uplift, runoff, and erosion. Soils exhibited relatively higher concentrations of organic carbon and more developed soil profiles in areas where these erosional factors play a limited role. 3rd place at the Denman Undergraduate Research Forum and Sigma Gamma Epsilon’s Austin A. Sartin Award at GSA

Pressures of Crystallization and Depth of Magma chambers beneath Hawai'ian Volcanoes

2012-04-27T06:18:28Z

Pressures of Crystallization and Depth of Magma chambers beneath Hawai'ian Volcanoes Ditkof, Julie The Hawai’ian Emperor Seamount Chain was formed by a mantle plume beginning about 80 Ma. The crust is raised by the heat of the plume while continuous eruptions of magma formed by decompression melting of the plume form the islands. The Hawai’ian Emperor Seamount Chain formed as the Pacific plate moved to the north and northwest across the nearly stationary plume. As the islands begin to slide off the plume, they subside back to the sea floor, forming seamounts. There are currently more than 80 undersea volcanoes stretching from the Aleutian Trench to the newly formed Loi’hi Seamount. Eight major islands, all of volcanic origin, make up the state of Hawai’i. Seismic and other geophysical data have been used previously to determine the depth of magma chambers beneath Hawai’ian Volcanoes. Yang et al (1996) created a method in which three equations are used to calculate liquid compositions along the pressure-dependent olivine-plagioclase-clinopyroxene coetectic. I used chemical analyses of glasses, which represent quenched liquid compositions, to calculate the pressure and temperature at which these liquids crystallize the minerals olivine, plagioclase, and clinopyroxene. The depth of crystallization can be calculated from these pressures. I filtered the data, removing any glasses with anomalous chemical compositions or with compositions that yielded pressures associated with unacceptably large errors. Plots of CaO versus MgO, P versus MgO, T versus MgO, and depth versus MgO for the filtered results reveal similar trends for Mauna Loa, Mauna Kea, three localities associated with Kilauea, and Loi’hi. The pressures range from 0.1 to 526 MPa and average 78 MPa. These results agree with geophysical data, and show that the magma chambers lie at shallow depths, about 10km with average depths between 3.5 x 10-6 and 11.28 km. Knowledge of the depths of chambers and pressures of crystallization is important for a number of reasons including understanding magma evolution, magma plumbing systems, and predicting when an eruption will occur.

Transport of organic carbon from the tropical volcanic island of Dominica, Lesser Antilles

2013-02-13T21:14:29Z

Transport of organic carbon from the tropical volcanic island of Dominica, Lesser Antilles Mondro, Claire Small rivers on high-standing islands (HSIs) around the world provide a substantial contribution to the total amount of carbon delivered to the global ocean. Dominica is a volcanic island, with little organic carbon found in the bedrock, making it a highly suitable natural laboratory to investigate the delivery of organic carbon solely from soils. A study comparing total carbon fluxes from 11 rivers on Dominica investigates the dissolved organic carbon (DOC) and particulate organic carbon (POC) yields from different regions of the island to determine a possible relation between carbon transport and geographic and environmental characteristics of the rivers. Results show DOC and POC yields that range from 0.2 to 3.67 t km-2 yr-1, ranking among the highest carbon yields to date worldwide. Phosphate concentrations are low (< 5 ppb) to non-detectable, suggesting a phosphate-limited nutrient system affected by chemical weathering. A strong correlation of DOC values with watershed area and silicate weathering yields indicates the importance of volcanic active margin terrains to the annual global carbon cycle.

Denaturing Gradient Gel Electrophoresis Analysis of Microbial Community Variation in Bleached and Non-bleached Montastraea faveolata

2012-04-13T12:48:21Z

Denaturing Gradient Gel Electrophoresis Analysis of Microbial Community Variation in Bleached and Non-bleached Montastraea faveolata Ringwald, Maximilian Previous studies have shown that coral maintain a symbiotic relationship between themselves, algal zooxanthellae, and bacteria. Although the role of bacteria in coral health is not fully understood, it is believed that some bacteria fix nitrogen for the zooxanthellae (Lema 2012), making the health of the microbial community very important to the overall health of the coral. As ocean temperatures continue to rise, bleaching has come to be a major cause of coral mortality. This study utilizes denaturing gradient gel electrophoresis (DGGE) to analyze the microbial communities of Montastraea faveolata under normal and bleached condition to determine what effects bleaching has on these microbial communities. After fragments were collected from nine parent colonies taken from three locations, half were exposed to heat stress in order to induce bleaching before analysis. Although much of the microbial community was conserved between samples, differences were found between fragments taken from different locations and those exposed to different treatments. In addition, a divergence was found between bleached fragments with similar beginning compositions which has not been found in previous studies.

Fossil Fuels: Examination and Prediction of Future Tends

2012-04-13T12:50:23Z

Fossil Fuels: Examination and Prediction of Future Tends Doherty, Joseph The accumulation of fossil fuels is a process that took hundreds of millions of years, yet in just the last few hundred years we have depleted a large percentage of the total amount formed. The future trends of fossil fuels are difficult to predict because of the many different factors that affect the production and consumption of each fossil fuel. To present accurate predictions about coal, oil, natural gas, and other energy sources like uranium, factors such as human population growth, the energy requirements in developing countries vs. developed countries, use of comparable fossil and renewable fuels, and environmental concerns and responses must be considered. By using conversion factors, the numerical energy values for each resource are equalized based on the thermal energy of oil. By this conversion the total amount of energy producible from the total reserves of each resource can be compared against one another. Taking into account these many variables, predictions results may accurately reflect the trends these fossil fuels will take in the future.

Detailed Stratigraphic Study of the Rose Run Sandstone in Coshocton, Holmes and Tuscarawas Counties, Ohio: A Potential Carbon Dioxide Injection Horizon

2012-03-07T07:17:19Z

Detailed Stratigraphic Study of the Rose Run Sandstone in Coshocton, Holmes and Tuscarawas Counties, Ohio: A Potential Carbon Dioxide Injection Horizon Flood, Joshua This study focused on using geophysical well logs to analyze the Rose Run sandstone, a member of the Knox group, as a possible candidate for carbon sequestration. The three main members of the Knox group are the Beekmantown dolomite, which overlies the Rose Run sandstone, which overlies the Copper Ridge dolomite. In Holmes, Coshocton, and Tuscarawas counties the Knox dolomite is truncated by an unconformity and overlaid by the Wells Creek shale. The Rose Run sandstone in the study area has a sufficient capacity of porosity (4%) to allow for injection and migration of supercritical brine. The thickness of the Rose Run is sufficient to act as a natural storage unit. The overlying Wells Creek dolomite is at least 10 feet thick and impermeable making it an excellent cap rock, preventing upward migration of CO2.

Geochemical Characteristics of Volcanism on the Azores

2011-12-02T07:18:23Z

Geochemical Characteristics of Volcanism on the Azores Ferritto, Mark Ocean islands are ideal research areas for petrologists because of their volcanic origins and the geochemical information they reveal of the mantle underneath. The Azores archipelago is no exception, lying within a unique geological setting which contains a mantle plume as well as tectonic plate boundary movement. Supported by these facts, the islands are an interesting and valuable place to study igneous petrology. By using major oxide data from the separate Azores, variation diagrams can be produced to display trends between different chemical ratios. Differences or similarities seen can be attributed to magma mixing, the complex plumbing system of the mantle plume, and the geographic placement of the islands near major tectonic features.

Phase stability of iron-nickel alloy at extreme pressures and temperatures: Implications for the Earth's core

2011-06-08T06:18:21Z

Phase stability of iron-nickel alloy at extreme pressures and temperatures: Implications for the Earth's core Hawrylak, Matthew The Earth’s core is primarily composed of iron, alloyed with 5-20% nickel. Interpretation of the history and evolution of the Earth’s inner core requires understanding of the properties of solid iron-nickel alloys under the high pressures and temperatures of the Earth’s interior. Each solid phase of iron is capable of producing seismic anisotropy if crystal lattices are preferentially aligned. Pure iron is hexagonally close packed (hcp) under core conditions. Incorporation of nickel shifts the crystallographic phase boundaries, raising the possibility that the core may not be purely hcp. Accordingly, this experiment determines how nickel concentration affects phase relations and elastic properties, as they would affect seismic wave speeds and the maximum possible anisotropy. X-ray diffraction patterns of compressed and heated samples of two iron alloys, one with 15% Ni and one with 5% Ni, were obtained from within a laser-heated diamond anvil cell. Within the pressure and temperature range of this experiment (20-45 GPa, 1200-2400 K), both fcc and hcp phases are present. Nickel partitions into the face centered cubic (fcc) phase with increasing temperature. This suggests, therefore, that higher nickel content will stabilize the fcc structure relative to the hcp structure at moderate pressures and temperatures. However, the nickel content of the core is not likely sufficient to stabilize fcc.

Geochemistry of Surface Water and Groundwater on the Campus of The Ohio State University

2011-06-21T17:52:21Z

Geochemistry of Surface Water and Groundwater on the Campus of The Ohio State University Westervelt, Claire This study determined the elemental and isotopic composition and origin of the water that is present in Mirror Lake, the Olentangy River, and the groundwater found on the south campus of The Ohio State University and investigated potential surface water and groundwater interaction. Samples were collected of local precipitation, Mirror Lake, the Olentangy River, and south campus well waters from October 2009 to May 2010. Samples obtained during the Autumn of 2009 have also been analyzed for nutrient (nitrogen and phosphorus) concentrations. The Olentangy River waters have much higher nitrate concentrations than Mirror Lake, with the groundwater being of intermediate concentration. Nitrogen is an indicator of anthropogenic activities influencing the chemical composition of natural waters (Rakowsky, 2000). Total nitrogen was highest in the river, reflecting drainage from agriculturally dominated land north of Columbus. The highest total phosphorus was found in the groundwaters. The highest dissolved silica levels were observed in the groundwaters, indicating that these waters have undergone more extensive silicate mineral weathering than the other waters. Stable isotope ratios of 18O/16O and 3H/2H were also analyzed in these samples, and the data indicated a much larger variation in the surface water than in the groundwater. Chloride concentrations were most variable in the Olentangy and highest in the South Campus Well (Gardner and Carey, 2004). This could be a result of road and sidewalk salt running off into the groundwater. Potassium concentrations were nearly constant both annually and between the samples. Calcium concentrations were highest in the South Campus well, possibly a result of water-rock interaction between the groundwater and Columbus Limestone underlying the sample location. Concentrations of sodium were significantly higher in both the South Campus Well and the Olentangy River than in Mirror Lake. This could be a result of road and sidewalk salt runoff. Graduation with Research Distinction

Strontium and Neodymium Isotope Stratigraphy of the Middle Ordovician and Implications for Appalachian Weathering

2012-04-26T22:58:41Z

Strontium and Neodymium Isotope Stratigraphy of the Middle Ordovician and Implications for Appalachian Weathering Howard, Amanda Regional tectonic events may alter the lithology and age of material weathered from the continents, leaving an imprint on the 143Nd/144Nd and 87Sr/86Sr compositions of seawater. Because of the long residence time of Sr compared to Nd, seawater 87Sr/86Sr changes should be globally synchronous and slow whereas 143Nd/144Nd changes may be rapid and regional. In the Ordovician, major stratigraphic shifts in both Sr (~ 0.001) and Nd (~ 10 epsilon units) have been documented. In the case of Sr, the global shift has been broadly attributed to changes in plate tectonics. For Nd, the shift has specifically been attributed to the uplift of the Appalachian Mountains (Taconic orogeny). However, no studies have been conducted that specifically address whether these changes in Sr and Nd are linked. Because the oceanic inventory of Nd is not balanced by seafloor hydrothermal input, the shift could be due to changes in continental weathering or ocean circulation patterns. A large seawater Nd shift that is due to enhanced continental weathering of young crustal rocks in the uplifted Appalachian Mountains may also be predicted to increase the flux of nonradiogenic Sr into the oceans. We have begun to test this hypothesis by producing the first integrated stratigraphic records of changes in seawater 87Sr/86Sr and 143Nd/144Nd. Our initial high-resolution curves were generated using bulk carbonate dissolved in acid and analyzed on a thermal ionization mass spectrometer, although we have also begun analyses with conodont apatite. These results from outcrops at Rocky Gap, Virginia and Roaring Spring and Union Furnace, Pennsylvania indicate a broad correlation of the initiation of Sr and Nd shifts in the upper Darriwilian to lower Sandbian stages (Middle-Late Ordovician transition). Other sections further west (e.g., Nevada) will be analyzed to compare the timing of Sr and Nd shifts in different epeiric sea water masses.

Image Processing of Petrographic and SEM Images

2011-06-02T23:20:56Z

Image Processing of Petrographic and SEM Images Gonsiewski, James Image processing software is used in many ways but as far as I have seen, it has not been used to analyze SEM or petrographic thin sections. This use will be very beneficial at the very least as a compliment to current mineral and lithologic studies but the potential is limitless with the right programming. The goal of my thesis was to test for the potential of using standard image processing software, IDL and ENVI, to analyze these thin sections. I have found it to be very feasible to use software packages already available for topographic and satellite image analysis. Isolating pixels and adjusting the display colors have proven to be a relatively simple tasks that can be put to use by someone with very little experience using this software. Though, more work will need to be done to put this to greater use, these programs have demonstrated a great deal of potential for this use in the field.

Natural Variability of Minor and Trace Elements in Two Species of Western Pacific Sclerosponges

2012-04-26T22:54:31Z

Natural Variability of Minor and Trace Elements in Two Species of Western Pacific Sclerosponges Borg, Dana Elemental proxies are used to reconstruct oceanic conditions that pre-date modern records. Such proxies have been established in corals, but few attempts have been made in sclerosponges. Acanthocheatetes wellsi (high Mg-calcite, collected from Palau and Saipan) and Astrosclera willeyana (aragonite, collected in Saipan) were stained in situ and left to grow on the reef for two years. We measured P, Pb, Sr and Ba (standardized to Ca) in two-year bulk samples from all specimens and 0.5mm high-resolution samples from two A. wellsi from Palau, one A. wellsi and one A. willeyana from Saipan. Interspecific differences in bulk P/Ca, Pb/Ca Sr/Ca, and Ba/Ca are likely due to mineralogical effects. Bulk sclerosponge P/Ca was higher, and Pb/Ca was lower, in Palau than in Saipan suggesting that these elements are sensitive to regional oceanographic conditions. At high-resolution, only P/Ca signatures were highly reproducible within and among species indicating that sclerosponges reliably record these elemental ratios in their skeletons. Furthermore, the apparent relationship between P/Ca, temperature, rainfall, and nutrient concentrations in Saipan indicates that sclerosponge P/Ca could be a paleonutrient recorder.

The effects of single and repeat bleaching on photosynthesis, respiration, and feeding rates in three species of Caribbean coral

2012-04-26T22:56:54Z

The effects of single and repeat bleaching on photosynthesis, respiration, and feeding rates in three species of Caribbean coral Baumann, Justin Bleaching events are predicted to increase in frequency and intensity as a result of rising sea surface temperatures. Paired fragments of the Caribbean corals Montastraea faveolata, Porites astreoides, and Porites divaricata were experimentally bleached (treatment) or nonbleached (control) in outdoor flow-through seawater tanks. Half of the fragments were immediately collected, and half were returned to the reef to recover for one year at ambient temperature, followed by repeat bleaching the following summer. Our findings show that the mounding coral P. astreoides is the most tolerant, and the branching coral P. divaricata is the least tolerant, of single bleaching. Unexpectedly, it is the branching P. divaricata that appears to be the most tolerant of repeat bleaching and indicates that the underlying mechanisms for bleaching resilience are fundamentally different in repeat bleached corals compared to singly bleached corals. This study provides insight into how coral species’ diversity and abundance could shift on Caribbean coral reefs in the coming decades.

Estimating Earthquake Risk in Northeast Ohio

2011-06-02T06:18:19Z

Estimating Earthquake Risk in Northeast Ohio Bennett, Bradley Other than isolated cases such as Charleston, South Carolina in 1886 and New Madrid in 1911-12, mid-continent earthquakes are not studied as much as plate boundary earthquakes. However, the Ohio Seismic Network monitors earthquakes in Ohio, and a high magnitude earthquake centered in the Northeast Ohio Seismic Zone could cause extensive damage. Maximum expected magnitude, expected depth, and site class for Ohio were studied and compared to results from the 1935 Timiskaming, Canada, 1989 Loma Prieta, California, 2009 L’Aquila, Italy, and 2010 Oaxaca, Mexico earthquakes. Based on the locations of greatest damage resulting from these earthquakes and the surficial geology in Ohio, the Northeast Ohio Seismic Zone is at a high risk area for earthquakes.

Influence of Natural Reductants on the Abiotic Reduction of Pentachloronitrobenzene in Prairie Pothole Lakes

2012-12-13T23:24:32Z

Influence of Natural Reductants on the Abiotic Reduction of Pentachloronitrobenzene in Prairie Pothole Lakes Voyles, Joseph Nitroaromatic compounds such as pentachloronitrobenzene (C6Cl5NO2) were once widely used as fungicides and pesticides in the United States and some (trifluralin and pendamethilin) are still in circulation. These compounds can contaminate natural systems including surface waters and sediments through overland runoff. In this study, the abiotic reduction of PCNB was examined in controlled laboratory systems containing natural wetland pore waters collected from the Prairie Pothole Lakes (PPL) in North Dakota. The PPL region is dominated by agricultural land use, which can impact the water quality of the lakes due to overland runoff containing organic contaminates. High levels of dissolved organic matter (DOM) and possible reduced sulfur species in pore waters could make the PPL reactive towards organic contaminates entering the system. Reduction of pentachloronitrobenzene to pentachloroaniline was observed by reaction with natural reductants in PPL pore waters. Iron analysis of the natural pore waters revealed a Fe(II) concentration of 14 μM, which makes it a relatively unimportant reductant. Even when compared to high concentration Fe(II)-only controls , natural pore waters degraded pentachloronitrobenzene at a faster rate. This indicates that the degradation in natural pore waters possibly occurred by reaction with other electron donors such as bisulfide or polysulfides in the presence of dissolved organic matter. Future work is necessary to elucidate the nature of the reductant and the precise role of DOM in the reduction of pentachloronitrobenzene.

Orientation Patterns of Bedding, Faults, and Veins in AND-1B Sedimentary Rock Core, McMurdo Ice Shelf Project: Significance for Terror Rift Evolution, Western Ross Sea, Antarctica

2013-06-03T19:45:14Z

Orientation Patterns of Bedding, Faults, and Veins in AND-1B Sedimentary Rock Core, McMurdo Ice Shelf Project: Significance for Terror Rift Evolution, Western Ross Sea, Antarctica Baumgartner, Lauren Renee The McMurdo Ice Shelf project recovered 1285 m of Neogene sedimentary rock core from the Victoria Land rift basin, Antarctica. The core contains over 1475 natural fractures of faults, veins, and clastic dikes. This study measured and mapped the attitudes and locations of bedding and natural fractures in select intact core intervals of AND-1B core to determine structure orientation. Whole-core scanned images were loaded into DMT CoreBase® software and manipulated to create digital intact intervals of core, joining core run breaks and correcting misfits that occurred during scanning. CoreBase® was used make independent orientation measurements of bedding and natural fractures within the core by drawing a ‘best fit’ sinusoid to each structure. Stereoplots were made for each intact interval to show whether there were systematic orientations of bedding and of each fracture type. The digital measurements were then compared with hand-measured orientations of the same structural features made during core logging. Twenty-four intact core intervals were analyzed and compared. Analysis of bedding orientation revealed that dip angle steepens with depth. Bedding within oriented intervals may be used to orient more core segments in the future. Results of comparing the two structural measurement methods indicate that both have strengths and weaknesses. Measurements during core logging can be made on fractures that are small and lack visible vein fill. These fracture types are not observable on digital images in the CoreBase® software. However, core logging methods can not measure the overall attitude of irregular veins and measurements on fractures exposed on the blue-scribed side of the core were commonly in error. Using the CoreBase® software, measurements are made viewing the whole core surface, giving a better overall attitude measurement. Weaknesses in CoreBase® methods are associated with the low resolution of the digital images once they are loaded into the software. This results in a smaller fracture population, missing many of the faults in particular, because they are not visible and therefore can’t be measured within CoreBase®. This comparison will help to guide future core-based fracture logging studies.