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Zeng, FangyuHolocene environmental evolution in the Yellow River Delta
MS, Kent State University, 2017, College of Arts and Sciences / Department of Geology
The Yellow River is the second largest river in China, world-famous for its highly sediment-laden water. The Yellow River delta is located in the transitional zone of the river sea interaction, where land and sea interact intensely. This area not only is the sink of the materials from the Yellow River, but also the source of the Yellow River dispersal system into the Bohai Sea. The Yellow River experienced many instances of channel switching and formed ten superlobes during the latest Quaternary. From 8800 yr. cal. BP., the Yellow River has experienced three transgressions. According to the study of Yi et al. (2014), the Yellow River deltas switch and form a new superlobe about every 1500 year. This thesis studied three sediment cores by applying geostatistical analysis and grain size VPCA analysis. I confirmed the approximately 1500-year periodicity for new superlobes by applying VPCA to grain size spectra and by correlating sediment cores in order to build age models to identify the different facies and layers. Smaller crevasse-splay cycles occurred on much shorter cycles, on the order of several decades. The ~1500-yr cycle is probably caused by the interaction of the Eastern Asian Winter Monsoon, the Kuroshio Current, and the Arctic Oscillation. Sea level change is also a very important consideration. Most major river deltas have been found to exhibit a 1000 to 2000-year cycle, which has been attributed to variations in sea level change. However, during the late Holocene, after 6000 Cal yr. BP, when sea levels had essentially reached the modern elevation, the Yellow River delta became quiescent and the Bohai Sea was more stable. In the first chapter, I discuss the Yellow River’s history and geological background and describe previous studies on the Yellow River delta. Chapter 2 discusses the methods that have been used in the thesis, specifically the Malvern Mastersizer and geostatical methods including VPCA (varimax principal component analysis) and it describes how to build age models and the quantitative stratigraphic correlation method (Match-2.3.1 in Matlab). I found that VPCA analysis documents that silt and clay are dominant components for cores YDZ-1, YDZ-2, and YDZ-3. The third chapter describes and discusses the wavelet analysis on VPCA components, and demonstrates that the Yellow River delta has a 1500~ year periodicity for the sediment deposition. Less

Committee:

Joseph D. Ortiz (Committee Member); Alison J. Smith (Committee Member); Neil Wells (Committee Member)

Subjects:

Earth; Geomorphology; Paleoclimate Science; Sedimentary Geology

Keywords:

Holocene Yellow River Delta Superlobe sediment grain size age models wavelet analysis

Barczok, Maximilian RWater Cycle of Closed-basin Lakes in the Northern Great Plains: A Model-Based Approach
Master of Science, The Ohio State University, 2015, Geological Sciences
Powerful and new hydrological codes have been developed over the last 15 years to help simulate complex hydrological problems. In this study, ParFlow (Ashby and Falgout, 1996), one of these codes, is used to research lakes, or “potholes,” in the Prairie Pothole Region (PPR) of central North America. The PPR is of great importance to wildlife (Batt et al., 1989), but not well described due to its large size. These potholes fluctuate greatly throughout seasons and changing climates. ParFlow is used to study the behavior of these lakes in a prairie setting. The purpose and scope of this study is to better understand the role and patterns of surface and groundwater under changing climatic and geological settings. This work builds upon the classic studies of Winter (1978; 1983). These simplified representations of lakes do not represent the complexity of the PPR and this study aims to improve knowledge of these systems using ParFlow and improving upon the groundwork laid out by Winter. ParFlow, a less commonly used hydrological code, is also examined for strengths and weaknesses in this setting. To achieve these goals, a hypothetical model of a hill slope with a depression in the center, serving as the lake, was created with ParFlow. Climatic data from 1985 to 2005 was taken of the PPR region to simulate realistic climatic forcing. Four different trials are used to research these problems. The first three trials are concerned with the effect of different geological features on the lake. The last trial investigates the question of time lag between a precipitation event and the reaction a lake experiences. This study determines that closed basin lakes appear to be sensitive to the geological setting of the area. Small changes in this setting resulted in significant changes of the lake. The behavior of the unsaturated zone and moisture content adds a complex relationship between precipitation and the response of a lake. Disappearing storage in the shallow subsurface shifts the system to create more surface runoff. It was also determined that the response of the lake does not only depend on the strength of the precipitation event, but also on the precipitation in the preceding years. As a region experiences a wetter climate, the response to precipitation events increases. ParFlow was examined for weaknesses and strengths. Its ability to be coupled with the Common Land Model (CLM) to realistically simulate climatic forcing is impressive, but its inability to realistically simulate lakes and to deal with sinkholes represents a significant weakness in this study. It is my conclusion therefore that additional modifications to ParFlow are necessary before it can be considered for use in a lake study.

Committee:

Frank Schwartz (Advisor); Durand Michael (Committee Member); Motomu Ibaraki (Committee Member)

Subjects:

Earth; Geology

Keywords:

ParFlow;groundwater;Nothern Great Plains;

chi, coppinger tReciprocity Among All Things: A Personal Endeavor in the Environmental Crisis
Bachelor of Fine Arts (BFA), Ohio University, 2016, Studio Art
We live in a world where climate change and water shortage threaten life. This text explores what it is to be an individual living in such a world. All things living are inevitably linked and dependent through a constant trading of energy. Each must give and receive in order to create a system that can sustain life. This is explored through text, art events and daily life.

Committee:

Duane McDiarmid (Advisor)

Subjects:

Aesthetics; Architecture; Art History; Design; Earth; Energy; Environmental Studies; Fine Arts; Performing Arts; Spirituality; Sustainability; Theoretical Physics

Keywords:

Life, Art, Climate Change, Water, Life Art, Tiny House, Performance Art

Chen, LinMEASUREMENTS OF AUTOCORRELATION FUNCTIONS USING A COMBINATION OF INTRA- AND INTER-PULSES
Master of Science, Miami University, 2015, Computational Science and Engineering
Incoherent scatter radar (ISR) is a versatile tool to study the ionosphere by measuring the autocorrelation function (ACF). Accurate ACF in the E-region is difficult to obtain because the relative short range limits the length of a pulse. The short correlation time of the ionosphere renders the correlation using the pulse-to-pulse technique useless. In the thesis, we study a method that combines intra-pulse and inter-pulse techniques and apply it to the data taken at Arecibo Observatory. We show simultaneously measured ACF’s at short and long lags and summarize the merits of ACF. Applications of ACF and its advantages are discussed. The technique used here will make the derivation of ionosphere parameters more accurate.

Committee:

Qihou Zhou (Advisor); Chi-Hao Cheng (Committee Member); Dmitriy Garmatyuk (Committee Member)

Subjects:

Aeronomy; Aerospace Engineering; Computer Engineering; Computer Science; Earth; Radiology

Keywords:

Incoherent scatter radar; ionosphere; E-region; parameters; autocorrelation function; accurate

Jeong, SeongsuTime Series Reconstruction of Surface Flow Velocity on Marine-terminating Outlet Glaciers
Doctor of Philosophy, The Ohio State University, 2015, Geodetic Science and Surveying
The flow velocity of glacier and its fluctuation are valuable data to study the contribution of sea level rise of ice sheet by understanding its dynamic structure. Repeat-image feature tracking (RIFT) is a platform-independent, feature tracking-based velocity measurement methodology effective for building a time series of velocity maps from optical images. However, limited availability of perfectly-conditioned images motivated to improve robustness of the algorithm. With this background, we developed an improved RIFT algorithm based on multiple-image multiple-chip algorithm presented in Ahn and Howat (2011). The test results affirm improvement in the new RIFT algorithm in avoiding outlier, and the analysis of the multiple matching results clarified that each individual matching results worked in complementary manner to deduce the correct displacements. LANDSAT 8 is a new satellite in LANDSAT program that has begun its operation since 2013. The improved radiometric performance of OLI aboard the satellite is expected to enable better velocity mapping results than ETM+ aboard LANDSAT 7. However, it was not yet well studied that in what cases the new will sensor will be beneficial, and how much the improvement will be obtained. We carried out a simulation-based comparison between ETM+ and OLI and confirmed OLI outperforms ETM+ especially in low contrast conditions, especially in polar night, translucent cloud covers, and bright upglacier with less texture. We have identified a rift on ice shelf of Pine island glacier located in western Antarctic ice sheet. Unlike the previous events, the evolution of the current started from the center of the ice shelf. In order to analyze this unique event, we utilized the improved RIFT algorithm to its OLI images to retrieve time series of velocity maps. We discovered from the analyses that the part of ice shelf below the rift is changing its speed, and shifting of splashing crevasses on shear margin is migrating to the center of the shelf. Concerning the concurrent disintegration of ice melange on its western part of the terminus, we postulate that change in flow regime attributes to loss of resistance force exerted by the melange. There are several topics that need to be addressed for further improve the RIFT algorithm. As coregistration error is significant contributor to the velocity measurement, a method to mitigate that error needs to be devised. Also, considering that the domain of RIFT product spans not only in space but also in time, its regridding and gap filling work will benefit from extending its domain to both space and time.

Committee:

Ian Howat, Dr. (Advisor); Alper Yilmaz, Dr. (Committee Member); Michael Durand, Dr. (Committee Member)

Subjects:

Climate Change; Earth; Geography; Remote Sensing

Keywords:

glaciology; remote sensing; Greenland; Antarctica; glacier flow; Landsat

Kornecki, Krystyna MariaCRETACEOUS CONFLUENCE IN THE COON CREEK FORMATION (MAASTRICHTIAN) OF MISSISSIPPI AND TENNESSEE, USA: TAPHONOMY AND SYSTEMATIC PALEONTOLOGY OF A DECAPOD KONSENTRAT-LAGERSTATTE
MS, Kent State University, 2014, College of Arts and Sciences / Department of Geology
The Late Cretaceous (Maastrichtian) Coon Creek Formation of Mississippi and Tennessee possesses a diverse and abundant assemblage of decapods including lobsters, ghost shrimp, and crabs. The formation lies in a temporally and paleogeographically significant location, situated between the Atlantic Coastal Plain and the Western Interior Seaway, shortly before the closing of the seaway and the K-Pg Mass extinction. Coon Creek decapods have been little studied since the fauna was first described in the 1920’s. A large collection of specimens, ranging in preservation from poor to excellent, has recently become available for study. Because of the visible variation in preservation, the abundant material, and the paucity of cuticular data of this type of preservation, an investigative study of elemental composition of the sediment and cuticle of six species of decapod from six families (Palinuridae, Nephropidae, Callianassidae, Dakoticancridae, Raninidae, and Retroplumidae) is conducted using material collected at the Blue Springs Locality in Mississippi. Cuticle, concretions, decapod burrow, and sediment from the site are analyzed with X-Ray Florescence and Elemental Reflectance for preliminary elemental composition and subsequent mineral composition. Concretions and the burrow were observed in thin section and were mapped for elemental distribution using Energy-dispersive X-Ray spectroscopy and dot mapping. The six species of decapod were analyzed using the same techniques. Taphonomic data supports preservation ranging from well preserved phosphatization to secondary alteration to silica-rich exterior and weathering clay minerals. Because the silica is not replacing the phosphatized exocuticle and microscopic structure of cuticle in cross section is not preserved in the silica layer, the cause of this alteration is uncertain. This preservation is un-like the decapod cuticle preservation of the concretions of the Bearpaw Shale Formation (Late Cretaceous) of Montana. Species of the Coon Creek Formation were re-assessed and assigned to modern taxonomic schemes. Sixteen species are identified and two new species are described including Hoploparia tennesseensis, Hoploparia mcnairyensis, Linuparus new species, Linuparus sp., Palaeopetrochirus enigmus, Seorsus wadei, Bournelyreidus new species, Cristipluma mississippiensis, Hoploparia georgeana, Mesostylus mortoni, Tetracarcinus subquadratus, Avitelmessus grapsoideus, Cretacoranina testacea, New genus new species (Carcineretidae), Dakoticancer australis, Prehepatus harrisi, and Latheticocarcinus atlanticus. This decapod assemblage shares common species with correlative units of the Western Interior Seaway, the Gulf Coastal Plain, and the Atlantic Coastal Plain, supporting the hypothesis that the Mississippi Embayment is an ecotone for North American decapods.

Committee:

Rodney Feldmann, Dr. (Advisor)

Subjects:

Earth; Geology; Paleoecology; Paleontology

Keywords:

Decapoda Cretaceous Maastrichtian Taphonomy Systematic Paleontology Paleobiogeography Lobster Crab Taxonomy Preservation Palinuridae Nephropidae Callianassidae Dakoticanceridae Raninidae Retroplumidae Majidae

Wilbur, Cricket C.A History of Place: Using Phytolith Analysis to Discern Holocene Vegetation Change on Sanak Island, Western Gulf of Alaska
Ph.D., Antioch University, 2013, Antioch New England: Environmental Studies
This study investigated a terrestrial climate proxy, phytoliths, as a complimentary approach to documenting the dynamics of present and past vegetation on Sanak Island, the largest island in a small island group in the eastern Aleutian archipelago, and as a new basis by which to interpret Holocene environmental variability in Alaska. A phytolith reference collection was established from 59 selected plant species of maritime tundra belonging to 27 families. The grass species and a sedge species produced abundant phytolith forms whereas the majority of dicotyledons in this study were trace producers of phytoliths. A paleoenvironmental reconstruction from fossil phytoliths recovered from a continuous lake sediment core indicates that sedges and cool season grasses were present on this landscape throughout most of the Holocene suggesting the long-term dominance of maritime climate on island vegetation. Adaptation and resilience of the modern vegetation on Sanak Island to a warming climate is suggested by the densities of silicified stomata recovered from six species of grasses, one species of fern, and one species of horsetail when compared to the paleoenvironmental reconstruction. The changes in stomata frequency in the plants on Sanak Island today may have connections to future changes in regional and global climate through the water cycle. Our changing climate is forcing ecosystems to migrate, acclimate or go extinct demonstrating that new insights into ecosystem responses to present and past environmental variation, and forecasting future ecological change are especially relevant today for ecologic and economic sustainability. The electronic version of this Dissertation is at OhioLink EDT Center, www.ohiolink.edu/etd.

Committee:

James W. Jordan, PhD (Committee Chair); Charles G. Curtin, PhD (Committee Member); Deborah M. Pearsall, PhD (Committee Member)

Subjects:

Archaeology; Botany; Climate Change; Conservation; Earth; Ecology; Environmental Science; Freshwater Ecology; Geology; Limnology; Native Americans; Natural Resource Management; Paleobotany; Paleoclimate Science; Paleoecology; Plant Biology; Pollen

Keywords:

Paleolimnology; Phytoliths; Phytolith Analysis; Aleutian Islands; Sanak Island; Western Gulf of Alaska; Stomata; Maritime tundra; Grasses; Dicotyldons; Arctic ecosystems; Climate change; Paleoenvironmental reconstruction; Holocene; Lake sediment

Shears, Andrew B.Hurricane Katrina and New Orleans: Discursive Spaces of Safety and Resulting Environmental Injustice
PHD, Kent State University, 2011, College of Arts and Sciences / Department of Geography
On August 29, 2005, a large tropical cyclone, named Hurricane Katrina, made landfall on the Gulf Coast of the United States. Despite following a track that mostly missed New Orleans, Katrina drowned this city by causing the failure of a protective levee infrastructure that surrounded population portions of the metropolitan area. In this majority African-American city, with a large number of impoverished people, Katrina caused over 900 deaths, tens of thousands of injuries, and left hundreds of thousands of residents displaced. However, the injustices of Katrina can be traced to the founding of New Orleans in 1718, when various government entities worked to alter the city's hazardous natural environment to promote development, beginning with French prison labor in the colony's earliest days, maintaining through a period of Spanish rule, and continuing to contemporary times under the administration of the United States. Indeed, the various infrastructural improvements serve as a discourse of safety, promoting capitalist development and residential settlement of a risky place. By the time Katrina struck, most of these residents, who took these discourses of safety very seriously, were generally of socioeconomically oppressed classes and least able to endure the consequences of that discourse's broken promise.

Committee:

James Tyner, PhD (Advisor); Mandy Munro-Stasiuk, PhD (Committee Member); Scott Sheridan, PhD (Committee Member); Robert Schwartz, PhD (Committee Member)

Subjects:

American History; American Studies; Area Planning and Development; Civil Engineering; Earth; Environmental Economics; Environmental Engineering; Environmental Justice; Environmental Studies; Geography; History; Land Use Planning; Modern History; Physical Geography; Pol

Keywords:

infrastructure; Hurricane Katrina; New Orleans; levees; flooding; environmental justice; hurricane; urban; mitigation; natural hazards; disaster

Da Silva, Ralston A.Green Computing – Power Efficient Management in Data Centers Using Resource Utilization as a Proxy for Power
Master of Science, The Ohio State University, 2009, Computer Science and Engineering
Many organizations are working towards reducing the carbon footprint of their data centers; i.e. reducing their power consumption. Server virtualization is used to decrease power consumption by consolidating multiple servers onto a few physical machines. Virtualization provides increased flexibility by providing a means to dynamically move virtual machines from one physical machine to another. Using resource utilization as a proxy for power, we build models of power consumption for individual server types, and use this information along with business value and SLA information, to efficiently allocate virtual machines to physical machines

Committee:

Rajiv Ramnath, PhD (Advisor); Jay Ramanathan, PhD (Committee Member); Sivilotti Paul, PhD (Committee Member)

Subjects:

Computer Science; Earth; Energy; Engineering; Industrial Engineering; Information Systems; Management; Technology

Keywords:

green computing; data center; power optimization; carbon footprint; resource utilization as a proxy for power; hardware profiling; application profiling; data center management architecture; power manager;

Klingensmith, Brandon C.GIS Based Biogeography of Cincinnatian (Upper Ordovician) Brachiopods with Special Reference to Hebertella
Master of Science (MS), Ohio University, 2011, Geological Sciences (Arts and Sciences)

Geographic ranges of type-Cincinnatian brachiopod species were reconstructed using Geographic Information Systems in order to analyze geographic distributions through space and time. Area polygons were digitized around species occurrence points plotted on the Cincinnatian outcrop belt (Ohio, Kentucky, Indiana), resulting in almost 100 individual maps spanning four depositional sequences. Individual species displayed patterns of habitat tracking as well as range expansion and contraction in response to regional sea level fluctuations. Statistical results show that species that established large geographic ranges preferentially survived the influx of extra-basinal species during the Richmondian Invasion.

A systematic revision of the North American articulated brachiopod genus Hebertella Hall and Clarke is proposed. Specimens representing 13 species were coded for morphologic character analysis. A single most parsimonious tree produced from analysis of character data shows the evolution of characters. Biogeographic patterns derived from the cladogram as well as those analyzed in the previous study suggest east to mid-continent dispersal of Hebertella species from the Middle to Late Ordovician.

Committee:

Alycia Stigall, PhD (Advisor); Elizabeth Gierlowski-Kordesch, PhD (Committee Member); David Kidder, PhD (Committee Member)

Subjects:

Biological Oceanography; Earth; Environmental Geology; Environmental Science; Geobiology; Geographic Information Science; Geological; Geology; Oceanography; Paleontology

Keywords:

Paleobiogeography; Cincinnatian; GIS; Ordovician; Invasive Species; Richmondian Invasion; Richmondian; Maysvillian; Hebertella; Stigall; Klingensmith

Khadka, Mitra B.Variation in Trace Metal Concentrations in A Fluvial Environment, Ottawa River, Toledo, Ohio
Master of Science (MS), Bowling Green State University, 2010, Geology
Surface sediment samples were collected from a 1000 m meander reach of the Ottawa River, Ohio and analyzed for trace metals (Zn, Pb, Sr, Mn, Cu, Cr, Co, Ba, Ti, Cd, and Hg) by Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES) to determine the local variability in their concentrations between geomorphic features. Eight metals (Zn, Pb, Sr, Mn, Cu, Cr, Co, and Ba) show significantly different concentrations between five fluvial geomorphic features namely, flood plains, point bars, lateral bars, pools, and riffles. Among the features, flood plains and lateral bars are places where flows are decelerated due to surface roughness and vegetation cover, promoting the deposition of fine-grained sediments and organic matter. Thus, flood plains and lateral bars consistently exhibit the highest metal concentrations. The lowest metal concentrations in point bars are attributed to relatively coarse-grained sediment and low organic matter content. The difference in mean metal concentration between flood plains and point bars ranges from 5 times for Co to 12.5 times for Pb. It was found that Zn, Sr, Mn, Cu, Cr, Co, and Ba are influenced by similar transport and interaction processes, and possibly have common sources, while Pb shows a weak to non-significant association with other metals indicating either a different mode of transport or separate anthropogenic sources. The concentrations of all metals in 89% of the samples are below the Threshold Effect Level (TEL) and the Probable Effect Level (PEL), and thus sediment contamination issues are to be minor concern in this section of the river. The finding that flood plains serve as sediment-associated metals sink can have important implications for monitoring and regulation, impact assessment, and remediation of contaminated sediments in metal contaminated section of the Ottawa River or for other rivers having similar geomorphological, hydrological, and sedmentological characters.

Committee:

Sheila J. Roberts (Advisor); James E Evans (Committee Member); Enrique Gomezdelcampo (Committee Member)

Subjects:

Earth; Environmental Science; Geochemistry; Geology; Hydrology

Keywords:

trace metal; fluvial geomorphology; sediment contamination; environment; ottawa river; flood plain

Zhu, LingxiaoHydrological Crustal Loading Deformation in Ohio
Master of Science (MS), Bowling Green State University, 2017, Geology
Yuning Fu, Advisor The aim of this study is to verify ground deformation caused by hydrological loading can be detected by GPS or GRACE measurement. The hypothesis of this research is both GPS and GRACE measured ground deformation are significantly influenced by hydrological loading deformation. Result indicates that the annual component of GPS measurements are about the same as modeled hydrological loading deformation and phase difference between them are as low as 0.15. Deeper research found out that GRACE modeled vertical displacements show clear spatial distribution rule when compared with hydrology data. Due to its limited spatial resolution, GRACE models long wavelength deformations while GPS reveal more local effecting elements. Both GRACE and GPS shows that area with more snow loading will have lower phase difference. In time domain, however, GRACE phase difference with hydrology suffered from missing measurements in 2013. Since GPS measured vertical deformation agrees well with hydrological data in that year, we think that it is possible to use GPS and hydrology data to interpolate the missing GRACE measurements. In years with smaller hydrology amplitude, both GPS and GRACE data showed smaller annual amplitude with hydrological data and phase difference between GPS and GRACE data are smaller. So as the years with larger annual amplitude of hydrological data.

Committee:

Yuning Fu, Dr. (Advisor); Sheila Roberts, Dr. (Committee Member); Peter Gorsevski, Dr. (Committee Member)

Subjects:

Earth; Geology

Keywords:

GPS; GRACE; deformation; hydrological loading

Treiber, Katie MDeepwater Channel Systems in the Orca and Choctaw Basins, Northern Gulf of Mexico
Master of Science, The Ohio State University, 2017, Earth Sciences
Turbidite channels are important conduits of clastic sediments into the deep ocean, with coarser-grained deposits creating potential reservoirs for hydrocarbons. In this study, three-dimensional seismic data and borehole logs from three industry wells were used to interpret channel systems, lithology, and overall depositional trends in the Orca and Choctaw mini-basins, located on the outer continental slope in the Gulf of Mexico in ~1645-2470 m (5400-8400 ft) of water. These mini-basins have previously been shown to have strong indications of gas hydrate in core samples and geophysical data, and the primary goal of this study was to identify coarse-grained sediments within channel systems that could serve as potential hydrocarbon reservoirs. To accomplish this, thirty-five channels were mapped in the ~2900 m (9500 ft) of sediment between the seafloor and top of salt. Channels were grouped into two broad morphological types to predict where coarse-grained sediments within each system were likely to occur. Basin depositional trends were also assessed to show how progressive salt withdrawal impacts channel occurrence by shifting topographic lows, in turn influencing where coarse-grained sediments are ultimately deposited. This research provides a detailed assessment of the turbidite channel systems in the Orca and Choctaw basins, and serves as model for future studies using seismic and well log analysis to interpret turbidite channel systems in deepwater basins.

Committee:

Derek Sawyer (Advisor); Ann Cook (Committee Member); Mike Wilkins (Committee Member)

Subjects:

Earth; Geological; Geology; Geomorphology; Geophysical; Geophysics

Keywords:

Seismic interpretation; Turbidite channels; Deepwater channels; Orca Basin; Choctaw Basin; geomorphology; Gulf of Mexico; Salt-withdrawal mini-basins

Matheny, Ashley MichelleDevelopment of a Novel Plant-Hydrodynamic Approach for Modeling of Forest Transpiration during Drought and Disturbance
Doctor of Philosophy, The Ohio State University, 2016, Civil Engineering
Land-surface and ecosystem models classify trees into functional types by phenology, leaf traits, and bioclimatic limits, while excluding their hydraulic properties. Frequently, trees are grouped within the same plant functional type, despite having opposing hydraulic strategies. Errors in the prediction of transpiration and carbon uptake by land-surface models have been linked to the coarse resolution of plant functional types. We pair a field and modeling study comparing tree species typically classified together within the same functional class to highlight their divergent responses to drought and disturbance, which result, in part, from contrasting hydraulic strategies. We measured sap flux, stem water storage, stomatal conductance, photosynthesis, rooting depth, and bole growth in tree species in disturbed and undisturbed field sites in Michigan from 2010-2015. Within our research site, two of these species represent opposing extremes of the proposed whole-plant hydraulic safety-efficiency spectrum. Red oak employs an efficient but high-risk hydraulic strategy (i.e., anisohydric stomatal regulation, highly conductive xylem, deep roots) while red maple relies on an `ultra’ safe strategy (i.e., isohydric stomatal regulation, less conductive xylem, shallow roots). Species-specific differences significantly influenced temporal patterns of stomatal conductance and overall transpiration responses to both drought and disturbance. Use of emergent tree-level hydraulic traits has the potential to improve model predictions of ecosystem-level transpiration and growth, particularly during periods of drought and disturbance. The implementation of such functional properties could be accomplished through either the recasting the plant functional type classification system to include whole-plant hydraulic traits, or explicitly representing plant hydrodynamics within land-surface models. Databases of species-specific hydraulic traits, such as the TRY Global Plant Trait Database, provide biologically relevant constraints for the governing hydraulic properties and will facilitate the implementation of both methods. Here, we propose a framework to incorporate whole-tree hydraulic strategies into land-surface models through the Finite-difference Ecosystem-scale Tree-Crown Hydrodynamics model version 2 (FETCH2). FETCH2 incorporates plant hydraulic traits at the root, stem, and leaf levels to mechanistically link stomatal conductance to dynamically resolved xylem water potentials. We use hydraulic traits from TRY and our field measurements to conduct a sensitivity analysis of FETCH2 parameters defining stomatal response, xylem conduit properties, and rooting depth. Through these properties, we are able to capture the effects of (an)isohydric stomatal regulation, xylem conductance and stem water storage representative of different xylem architectures, and rooting depth on simulated transpiration. Inter- and intra-daily dynamics of simulated transpiration vary for each tested parameter combination, emphasizing the necessity of including traits at all three levels (roots, stems, and leaves) in the framework of a whole-plant hydraulic strategy. Incorporation of these functional traits into FETCH2 allows us to replicate the disparate patterns of water acquisition and use of species with contrasting hydraulic strategies. Holistic plant hydraulic representation in models, through informed plant functional groupings or the incorporation of plant hydrodynamic models like FETCH2, will not only improve predictions of transpiration, growth, and mortality, but also simulations of the surface energy budget and the global carbon and water balances.

Committee:

Gil Bohrer, PhD (Advisor); Peter Curtis, PhD (Committee Member); Gajan Sivandran, PhD (Committee Member); Jeffrey Bielicki, PhD (Committee Member)

Subjects:

Biogeochemistry; Biographies; Civil Engineering; Earth; Ecology; Hydrologic Sciences; Hydrology; Water Resource Management

Keywords:

hydrology, land-surface modeling, ecohydrology, vegetation modeling, vegetation hydrodynamics model, drought, disturbance

Wan, JunkunJoint Estimation of Vertical Land Motion and Global Sea-Level Rise over the Past Six Decades Using Satellite Altimetry and Tide Gauge Records
Doctor of Philosophy, The Ohio State University, 2015, Geodetic Science and Surveying
Determination of the 20th and early 21st century sea level rise and understanding the geophysical causes leading to sea level rise is a significant scientific topic. Satellite radar altimeter has been providing continuous and near-global sea level measurements since 1992. Despite of the fact that multiple satellite altimeter measurements have reached a 23-year data record, it is still too short to isolate the definitive sea level rise signal from the contamination of interannual or longer oceanic variability. In contrast, global tide gauges measure the relative sea level and have data records as long as 200 years, but the measurements are susceptive to or contaminated by the vertical motion of the solid Earth. Despite the availability of geophysical models or collocated GPS stations at the tide gauge benchmarks, the separation of vertical land motions from long-term sea level signal in tide gauge records remains to be a challenge to be practically applicable to improve sea level rise projections. To improve the accuracy of altimeter estimated geocentric sea level over the last 23 years, we process altimeter data from different satellite missions. Least-squares collocation technique has been applied in the generation of multi-satellite altimeter gridded data products, 1992–2015, with updated estimates of reference frame offsets. Furthermore, we improved the sea level data record quality, based on comparisons with available in situ tide gauges and increased data points, over seasonally sea-ice covered Arctic Ocean from our reprocessed ERS-1 and ERS-2 altimeter measurements. Finally, our composite altimeter data set yielded a global sea level trend estimate of 2.8±0.6 mm/yr, and the regional trend estimate of 2.3±1.3 mm/yr for the Arctic Ocean, 1992–2015, respectively. To improve vertical land motion estimates at world’s tide gauge locations for the improved recovery of sea level rise signal, we proposed a new method, based on adjustment algorithm and sea level reconstruction, to combine radar altimeter and tide gauge data. First, we validated our multi-satellite altimeter sea level are consistent with in situ sea level from the global tide gauge network. Results comparing 559 globally distributed tide gauges show that our multi-satellite sea level data has an average correlation with tide gauge sea level at 0.85±0.09, and standard deviation of difference of 4.4±1.6 cm. Application of regional adjustment algorithms results in globally selected 158 tide gauge vertical motion estimates with the difference of –0.19±1.67 mm/yr against independent GPS@Tide gauge vertical motion solutions. The result is a significant improvement over the priori vertical motion estimates with an average difference of –0.11±3.15 mm/yr against the independent GPS rates. Finally, we further improved the algorithm with an iterative procedure to separate the vertical motion at 417 world’s tide gauges and sea level rise, by combining altimetry and tide gauge data to simultaneously estimate vertical motion at the tide gauge locations, and to reconstruct the global sea level variations, 1950–2012. The resulting vertical motion solution yields a discrepancy at 0.01±1.67 mm/yr against 210 independent GPS rates, and an average rate of global sea level rise at 1.70 mm/yr.

Committee:

C.K. Shum (Advisor); Christopher Jekeli (Committee Member); Alan Saalfeld (Committee Member)

Subjects:

Earth; Geophysics

Bedocs, Justin ANames and Geographic Features: An Internship with the U.S. Geological Survey
Master of Environmental Science, Miami University, 2016, Environmental Sciences
Place names are vital to orienting ourselves in the world. In ancient times, people must have had names for places like hunting grounds or berry groves. This act of naming roughly delineates geographic features which can be revisited and described to others, affixing an added cultural meaning to that place. Place naming has since come a long way. Official place names for the United States and its territories are managed by the United States Geological Survey (USGS), National Geospatial Technical Operations Center (NGTOC). This report details my experience working in the Geographic Names Unit. As a Pathways Career Intern, my main duties were to manage the Geographic Names Information System (GNIS), a database containing official place names for features outlined on federal topographic maps. Most of the work involved duplicate names; an issue where there are two name records for one feature, often indicating that one record is a copy and should be deleted. Sometimes the two records were not copies, and the correct locations were identified by visually analyzing historic and recent maps. The coordinates were then updated respectively in the GNIS. I gained valuable experience reading topographic maps, identifying features and managing a large database of geographic names.

Committee:

Robbyn Abbitt, MS (Committee Chair); Suzanne Zazycki, JD (Committee Member); Mark Allen Peterson, PhD (Committee Member)

Subjects:

Cartography; Computer Science; Cultural Anthropology; Earth; Environmental Science; Geographic Information Science; Geography; History; Information Science; Information Technology; Language; Native American Studies

Keywords:

Places; Names; Place Names; Geographic Features; Geography; Cultural Anthropology; Linguistics; Topography; Naming Disputes; Denali; Sense of Belonging; Community; Topographic Maps; Stakeholder Groups; GNIS; Geographic Names Information System

Dai , ChunliSource Parameters Inversion for Recent Large Undersea Earthquakes from GRACE Data
Doctor of Philosophy, The Ohio State University, 2015, Geodetic Science and Surveying
The north component of gravity and gravity gradient changes from the Gravity Recovery And Climate Experiment (GRACE) are used to study the coseismic gravity change for five earthquakes over the last decade: the 2004 Sumatra-Andaman earthquake, the 2007 Bengkulu earthquake, the 2010 Maule, Chile earthquake, the 2011 Tohoku earthquake, and the 2012 Indian Ocean earthquakes. We demonstrate the advantage of these north components to reduce north-south stripes and preserve higher spatial resolution signal in GRACE Level 2 (L2) monthly Stokes Coefficients data products. By using the high spherical harmonic degree (up to degree 96) data products and the innovative GRACE data processing approach developed in this study, the retrieved gravity change is up to –34±1.4 µGal for the 2004 Sumatra and 2005 Nias earthquakes, which is by far the highest coseismic signal retrieved among published studies. Our study reveals the detectability of earthquakes as small as Mw 8.5 (i.e., the 2007 Bengkulu earthquake) from GRACE data. The localized spectral analysis is applied as an efficient method to determine the practical spherical harmonic truncation degree leading to acceptable signal-to-noise ratio, and to evaluate the noise level for each component of gravity and gravity gradient change of the seismic deformations. By establishing the linear algorithm of gravity and gravity gradient change with respect to the double-couple moment tensor, the point source parameters are estimated through the least squares adjustment combined with the simulated annealing algorithm. The GRACE-inverted source parameters generally agree well with the slip models estimated using other data sets, including seismic, GPS, or combined data. For the 2004 Sumatra-Andaman and 2005 Nias earthquakes, GRACE data produce a shallower centroid depth (9.1 km) compared to the depth (28.3 km) from GPS data, which may be explained by the closer-to-trench centroid location and by the aseismic slip over the shallow region. For the 2011 Tohoku earthquake, the inversions from two different GRACE data products and two different forward modeling produce similar source characteristics, with the centroid location southwest of and the slip azimuth 10° larger than the GPS/seismic solutions. The GRACE-estimated dip angles are larger than that from GPS/seismic data for the 2004 Sumatra-Andaman and 2005 Nias earthquakes, the 2010 Maule, Chile earthquake, and the 2007 Bengkulu earthquake. These differences potentially show the additional offshore constraint from GRACE data, compared to GPS/seismic data. With more accurate and higher spatial resolution measurements anticipated from the GRACE Follow-on mission, with a scheduled launch date in 2017, we anticipate the data will be sensitive to even smaller earthquake signals. Therefore, GRACE type observations will hopefully become a more viable measurement to further constrain earthquake focal mechanisms.

Committee:

C.K. Shum (Advisor); Michael Bevis (Committee Member); Christopher Jekeli (Committee Member)

Subjects:

Earth; Geophysics

Kapela, Steven J.The Boy with the Aluminum Hat
Master of Arts (MA), Ohio University, 2014, English (Arts and Sciences)
These poems are the culmination of an experiment toward understanding how certain celestial phenomena influence our inner and outer lives in an abundance of ways that simply go undetected by the senses. In an effort to both understand the inner life's relation to the outer, the poems undertake the project (through a dream-like tone, crafted to convey the speaker's journey of rediscovering senses) of understanding the relationship of humans and the world, perspective and self. Split between the concepts of refraction and reflection, The Boy with the Aluminum Hat is a metaphor, a voice-piece to vocalize both the paranoia of never understanding our lives and the desire to know the truth of existence. Both sections collide with the anxiety of living in the world on a daily basis. Simultaneously, the poems illustrate the body's relation to this world that it is rooted to and from which it is occasionally uprooted.

Committee:

Halliday Mark (Advisor)

Subjects:

American Literature; Earth; Electromagnetics; Personality

Keywords:

Poetry; poems; paranoia; space; moon; stars; sun; aluminum hat; the boy; Steven Kapela; Refraction; Reflection; Geography of Dreams; Dreams; Nightmares; distant; signals; Heart; Soul; time; timelessness; autobiographical

Franţescu, Ovidiu DanielBrachyuran decapods (including five new species and one new genus) from Jurassic (Oxfordian-Kimmeridgian) coral reef limestones from Dobrogea, Romania
MS, Kent State University, 2009, College of Arts and Sciences / Department of Geology
Analysis of the fossil decapod faunas in coral reefs from localities at Topalu and Piatra in Central Dobrogea, Romania, yielded five new species and one new genus belonging to superfamilies Homolodromioidea Alcock, 1899, and Glaessneropsoidea Patrulius, 1959. Comparison of the abundance and diversity of decapod faunas from these Jurassic coral reefs with the abundance and diversity of decapod faunas from sponge-algal reefs in the same geographic area and of the same age (middle Oxfordian) has led to some interesting paleoecological differences. The coral reef environments yielded 30 specimens of decapods that represented six families in seven genera and ten species, including the new taxa. The sponge reef environments yielded 22 specimens that represented only three families with four genera and five species. These two different types of environments share only one genus in common, and no species. Thus, the number of specimens is similar, but the diversity is markedly different. Furthermore, the nearly complete taxonomic difference between the environments (no shared species and only one shared genus) suggests that the environments selected for different adaptations, leading to niche partitioning within and between habitats. The higher abundance and diversity in the coral environments may reflect a higher number of niches available for decapods, shallower water depth, higher oxygen content and/or difference in energy levels in the two environments, making coral reefs a more suitable environment for decapods.

Committee:

Rodney Feldmann, Dr. (Advisor); Carrie Schweitzer, Dr. (Committee Member); Neil Wells, Dr. (Committee Member)

Subjects:

Earth; Geology; Paleoecology; Paleontology

Keywords:

Decapod; Romania; Dobrogea; Jurassic; Brachyurans; Coral reefs.

Abt, Tin LianDetection of a Local Mass Anomaly in the Shallow Subsurface by Applying a Matched Filter
Doctor of Philosophy, The Ohio State University, 2011, Geodetic Science and Surveying
The task is to locate a mass anomaly, particularly a void, in the near subsurface based on gravity, gravity gradients, and magnetic field data.The motivation for this search rises from multiple areas of applications such as urban planning, mining, archeology, and extraterrestrial science. Assuming that the signal generated by the sought mass anomaly is approximately known and can be described by the signal of a three-dimensional prism, a Matched Filter (MF) is implemented to detect this signal buried in the relatively strong noise of the geologic background. The background noise is described in the filter function by covariances. One important aspect of the current study is, therefore, to derive the covariance matrix that accounts for the relation between gravity, gravity gradients, and the magnetic field. It turns out that the choice of covariance function can have a significant influence on the MF performance. The aim of this research is to answer some fundamental questions regarding the various combinations of data types, the estimation of the depth or orientation of the mass anomaly, as well as the optimal number of observed profiles. All tests are carried out by Monte Carlo simulations, which include randomized simulated background fields. In addition, a statistical interpretation based on the Neyman-Pearson hypothesis test is provided. It determines the probabilities that either a sought anomaly is not detected or that some background noise is mistaken for the sought anomaly. The simulation results lead to the conclusion that the MF is a very strong tool to detect the sought anomaly along an observed profile as it searches for the maximum Signal-to-Noise ratio. Therefore, the MF is able to detect anomalies buried in the background noise even if they are not directly visible in the data set. A data set of either gravity gradients or the magnetic field leads to more successful detections compared to a data set of gravity. The combination of several gravity gradient components as well as the magnetic field further improves the filter performance. The MF is highly sensitive to the depth of the sought anomaly but far less sensitive to its horizontal orientation. As a consequence, it is possible to determine a rough estimate for the depth but not for the orientation, which, however, can be approximated by measuring multiple profiles.

Committee:

Christopher Jekeli, Prof. (Advisor); C.K. Shum, Prof. (Committee Member); Ralph von Frese, Prof. (Committee Member); Gregory Kilcup, Prof. (Committee Member)

Subjects:

Earth; Geophysics; Statistics

Keywords:

Matched Filter; Gravity Gradients; Magnetic Field; Void Detection

Atchison, Christopher LawrenceThe Significance of Access: Students with Mobility Impairments Constructing Geoscience Knowledge Through Field-Based Learning Experiences
Doctor of Philosophy, The Ohio State University, 2011, EDU Teaching and Learning

The post-secondary geology curriculum typically requires completion of multiple field-based education components. The importance of field-based learning experiences is well documented in geoscience education literature. However, due to these field requirements, persons with mobility impairments face multiple barriers to obtaining a higher education in the geosciences. Furthermore, the lack of exposure to career opportunities in the geosciences potentially creates a perception that most geoscience careers do not accommodate graduates with mobility impairments. As a result, students might feel discouraged from pursuing undergraduate and graduate level degrees in geology.

An assumption exists that most traditional field environments are inaccessible to students with mobility impairments. A main objective of this study was to first determine how experience in a geologic field environment assists in the overall construction of cave geology content knowledge for students with mobility impairments. An effective evaluation of this field experience required an understanding of how students interact with their environment. Individual case studies of the participants’ lived experience with (and within) a traditional field-site provided an understanding of how geological content knowledge was constructed in the face of field-related barriers. Also assuming that knowledge is independent of one’s physical ability, this study focused on understanding the potential environmental and physical barriers that students with mobility impairments maintain with respect to field-based education. Therefore, participants’ experience in a cave geology field environment was investigated through their personal perception of the surroundings. This exploration was not intended to differentiate them from the rest of society by what they do or do not know, what they can or cannot do, but to assist them in obtaining the accessibility and content knowledge of a geoscience field-based curriculum. An understanding of these first-hand perceptions provides a valuable foundation for field-based science educators to include, accommodate and provide equal access for students with mobility impairments.

As part of this study, participants with mobility impairments learned about geologic processes in a classroom setting and then participated in a field-based learning experience relative to those processes. Through an assumption that most traditional field environments are inaccessible to students with mobility impairments, a primary objective of the study was to determine how first-hand experience in a geologic field environment assists in the overall construction of content knowledge for students with mobility impairments. An evaluation of this field experience required an understanding of how these students interact with the environment through daily routines, which was accomplished through six individual case studies of the participants’ lived experience. This dissertation presents both quantitative and qualitative data related to the construction of geoscience content knowledge and how personal, environmental and societal barriers were perceived by the participants and how these barriers could be minimized in the planning of future geologic field experiences.

Committee:

Karen E. Irving, PhD (Advisor); Garry D. McKenzie, PhD (Committee Member); Scot E. Danforth, PhD (Committee Member)

Subjects:

Adult Education; Earth; Education; Geological; Geology; Higher Education; Science Education; Teaching

Keywords:

disabilities; mobility impairments; geology; cave and karst; Mammoth Cave National Park; geoscience education; accessibility; inclusion; accommodation; field-based learning; transformative learning theory;

Witherow, Rebecca A.Minor Alkaline Earth Element and Alkali Metal Behavior in Closed-Basin Lakes
Doctor of Philosophy, The Ohio State University, 2009, Geological Sciences
Hydrologically closed basins in arid environments often pose ideal conditions for the development of inland saltwater lakes. In these regions, where the hydrology is balanced by dilute inflow waters and evaporation, these closed-basin lakes may progress through various degrees of evapoconcentration. This process may result in the precipitation of simple salts and the alteration of the relative chemical composition of a lake. Such “geochemical evolution” processes have been studied in detail particularly for the so-called major ions (Na, Ca, K, Mg, Cl, SO4, HCO3+CO3) and Si, but little work has been done on ions of moderate concentration. Due to the evaporative nature of these systems, the alkali metals, Li and Rb, and alkaline earth elements, Sr and Ba, may become highly concentrated and play a significant role in determining the geochemistry of a saline lake. Here, I present the first comprehensive study of the transport and fate of the minor alkali elements, Li, Rb, Sr, and Ba, in three distinct geographic settings illustrating three types of saline lakes as determined by their major anion abundance. Using lithium isotope analysis and mass balance calculations, I show that the minor elements in the McMurdo Dry Valleys are transported to “chloride-type” lakes by a combination of precipitation, chemical weathering and salt dissolution. Sr and Ba show evidence of removal in the lakes, but Li and Rb appear to be conservative to extremely high concentrations. This work discusses the potential removal mechanisms of these ions, particularly the formation of major and minor sulfate and carbonate minerals in the lakes. A major finding of this study is that brine type determines the removal mechanism of Sr and Ba, particularly if they are removed as sulfate or carbonate minerals. This study provides a platform for future exploration of the role of these and other minor elements in inland brines and playas.

Committee:

William Berry Lyons (Advisor); Anne Carey (Committee Member); David Porinchu (Committee Member); Ozeas Costa (Committee Member); William Green (Committee Member)

Subjects:

Biogeochemistry; Earth; Environmental Science; Geochemistry; Geology

Keywords:

Antarctica; McMurdo Dry Valleys; Great Basin; lithium isotopes; alkali metals; alkaline earths; terminal lakes; geochemical evolution; saline lakes; strontium; rubidium; barium

Popovich, Patricia A.Re-Connecting Adolescents with Nature using Environmental Art and Photography
Master of Arts, Ursuline College, 2008, Art Therapy and Counseling
The lives of today's youth are so influenced by technology that many believe they are rapidly disconnecting from nature and its benefits. This grounded theory research explores meaningful interactions within a natural setting, environmental art, and the use of digital photography with adolescents. Data was gathered from questionnaires, personal process reflections, and the researcher's observations and interactions with the participants. Resources supporting the basis for this research were derived from environmental art, ecopsychology research, and ancient cultural wisdom. Conclusions from this study indicate that through the use of environmental art and photography, adolescents can reconnect with a natural environment. Through their active participation within a natural setting, they can enhance well-being, raise awareness regarding ecological commitment, enhance self-awareness, and recognize the power of place.

Committee:

Gail Rule-Hoffman, M.Ed. (Committee Chair); Cecile Brennan, Ph.D. (Committee Member)

Subjects:

Art Education; Developmental Psychology; Earth; Educational Psychology; Mental Health; Native Americans; Personal Relationships; Psychology

Keywords:

art therapy; ecopsychology; environmental art; photography; adolescents; nature; Native American wisdom;

Mizuno, JunNumerical Analyses of Potential Losses of Freshwater Resources in Coastal Aquifers Caused by Global Climate Change Using an Appropriate Boundary Condition
Master of Science, The Ohio State University, 2008, Geological Sciences
Coastal regions face various hydrological problems including saltwater intrusion in the aquifers. One of the processes affecting saltwater intrusion is sea-level rise caused by global climate change. Sea-level rise could enhance saltwater intrusion and cause a decrease in freshwater resources from aquifers. The boundary condition with variable mass flux and constant pressures, the Dynamic Mass Flux Boundary (DMFB), was examined for the numerical simulation of saltwater intrusion in coastal aquifers. The results showed the DMBF to be more accurate than the typically-used Dirichlet boundary. Using the DMFB, the effects of potential sea-level rise on saltwater intrusion and the freshwater supply in coastal aquifers with heterogeneous permeability fields were investigated. The impact of pumping was also examined in conjunction with the effects of sea-level rise. It is found that heterogeneous permeability fields greatly enhanced the saltwater intrusion process under the combined effects of sea-level rise and pumping.

Committee:

Motomu Ibaraki (Advisor); Franklin W. Schwartz (Committee Member); Garry D. McKenzie (Committee Member)

Subjects:

Earth; Environmental Science; Geology; Hydrology

Keywords:

numerical analysis; saltwater intrusion; heterogeneous media; climate change

Millan, CristinaSyntectonic Fluid Flux in a Glaciated Rift Basin: Record from vein arrays in the AND-1B and AND-2A sedimentary rock cores, Victoria Land Basin, Antarctica
Doctor of Philosophy, The Ohio State University, 2013, Geological Sciences
Two Neogene sedimentary rock cores recovered by the ANDRILL project from the Victoria Land rift basin of Antarctica contain 1174 mineralized fractures that are the focus of this study. Veins are assigned into extension, shear, and extension-shear kinematic groups and into relatively `early’ and `late’ temporal generations based on initial core fracture logging, refined by microscopic, ultramicroscopic and petrologic characteristics. Vein fill is dominantly calcite, with subordinate zeolite, chlorite and pyrite. Calcite crystal shapes and growth patterns document diffusive and advective flow of fluids into, and along, veins during opening- and shear-mode displacements. In addition, the crystal textures indicate that fluid overpressures were sufficiently high in many cases to exceed the lithostatic stress and to hold fractures open during mineral precipitation. The patterns of vein distribution and frequency with depth in the core do not show any spatial correlations with horizons interpreted to mark grounded ice advance over the depositional site, and subglacial deformation appears to be an unlikely cause of vein formation. Instead, in the AND-1B core, there is a strong spatial correlation between vein abundance and volume and glass-bearing, volcaniclastic sedimentary intervals. Alteration and diagenetic reactions have clearly influenced the mechanical behavior of sediment during compaction and dewatering. Vein arrays appear to record 3D strain marked by contraction in the vertical direction, due to sedimentary and/or glacial overburden, and radial extension recorded by the trimodal orientation patterns of extension and shear-mode veins. Carbon and oxygen isotope ratios measured in vein calcite show strong variations with depth in the AND-1B veins, whereas AND-2A veins have linear depth trends. There are systematic shifts of vein calcite isotope values with respect to bulk carbonate values in host rocks. These patterns signal both the influence of fluid-host rock interactions in rapidly altering volcaniclastic intervals, and mixing of fluids from different sources via fracture pathways. Vein arrays in the Neogene strata of the Victoria Land Basin are interpreted to record interaction between diagenetic and structural processes during dewatering and compaction of the basin sediments. Veins formed during progressive compactional deformation. Early veins formed by repeated brittle fracturing of strong host rocks, then record ductile deformation after the host rock lost strength. The loss of strength is attributed to dissolution of early cement and framework collapse due to diagenetic changes. During ongoing compaction and sediment dewatering, there was continued brittle deformation and mineral precipitation. The unusual deformation path of alternating brittle and ductile sediment behavior during compaction appears to be linked with pervasive alteration of the volcanic components in the sediments. High fluid pressures and the repeated fracturing episodes produced an interconnected network of extension and shear-mode veins that formed a `fault-fracture mesh’ that provided structural permeability and served as dewatering conduits as the strata compacted and lithified. Systematic isotopic variations in vein calcite precipitated from the fluids resulted from both diagenetic alteration of sediments and mixing of fluids from different sources and was facilitated by the interconnected fracture network transecting the basin strata.

Committee:

Terry Wilson (Advisor)

Subjects:

Earth; Geological; Geology

Keywords:

rift basin; geology; mineralized veins; fractures; diagenesis; volcanic alteration; veins; isotopes; deformation

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