Master of Science / Department of Geology / Saugata Datta / More than 75 million people in the Bengal Delta of eastern India and Bangladesh are exposed to drinking water with dangerously high arsenic (As) concentrations; the worst case of environmental poisoning in human history. Despite recognition of dangers posed to chronic exposure to drinking water with elevated As, its biogeochemical cycle is inadequately constrained in groundwater flow systems due to its complex redox chemistry and microbially-mediated transformations. Arsenic concentrations in Bengal Delta sediments are comparable to global averages, but its highly heterogeneous spatial distribution (on scales of meters to kilometers) in sediments and groundwaters is poorly understood. Though many research efforts have targeted understanding this heterogeneity in Bangladesh, less work has been done in eastern India. Murshidabad (23°56.355‘N, 88°16.156‘E), an eastern district in West Bengal, India, where groundwaters are highly As-affected (~4000 μg/l), was chosen as our study area. Research objectives were: (1) characterize sediment cores (mineralogically, geochemically) and groundwaters (hydrochemically, isotopically) in areas with contrasting As concentrations—west (low-As) and east (high-As) of river Bhagirathi, a major distributary of Ganges flowing through the heart of Murshidabad; (2) describe and understand the extent of spatial variability, laterally and vertically, of dissolved As concentrations in shallow (< 60 m) aquifers, comparing sediment core chemistry to water chemistry; (3) identify source(s) of aquifer recharge and (4) role(s) of inorganic carbon within the aquifer to understand the bioavailability and mobilization of As from sediments to groundwaters. Mineralogical differences between high-As (grey) and low-As (orange-brown) sediments, were the presence of greater amounts of micas, Fe- and Mg-rich clays, amphiboles, carbonates, and apatite in high-As sediments; these were virtually absent from low-As sediments. In high-As areas, As was associated with amorphous and poorly-crystalline Fe-oxyhydroxide phases and labile (specifically-sorbed) phases, especially where Fe(II):Fe[subscript]T was high in the sediments. High-As groundwaters had high As(III):As[subscript]T, iron, bicarbonate, phosphate, and ammonium, and low concentrations of chloride and sulfate. Dry season precipitation was probably the main source of aquifer recharge; lighter values of [superscript]13C in dissolved inorganic carbon resulted from oxidation of natural organic matter. This study points to an idea that both microbially-mediated oxidation-reduction and competitive ion-exchange processes occurring in shallow aquifers of Murshidabad drive As mobilization and sequestration by aquifer sediments.

Master of Science / Department of Geology / Sambhudas Chaudhuri and Matthew Totten / The current model of hydrocarbon generation involves the thermogenic maturation of organic material as a consequence of burial. This process only considers energy generated from temperature increase due to burial. The majority of organic rich source beds contain high concentrations of radioactive elements, hence the energy produced from radioactive decay of these elements should be evaluated as well. Previous experiments show that α-particle bombardment can result in the generation of hydrocarbons from oleic acid. This study investigates the effects of γ-rays in a natural petroleum generating system. In order to determine the effects of γ-rays, experiments were conducted using cesium-137 as the γ-ray source at the KSU nuclear facilities to irradiate crude oil and organic material commonly found in petroleum systems. The samples were then analyzed using Fourier Transform Infrared Spectroscopy (FTIR) and Rock-Eval pyrolysis to determine changes in the samples. The FTIR results demonstrated that γ-radiation can cause the lengthening and/or shortening of hydrocarbon chains in crude oils, the dissociation of brine (H2O (aq)), the production of free radicals, and the production of various gases. These changes that come from γ-radiation hold the possibilities to distort the configuration of organic molecules, dissociate molecular bonds, and trigger oxidation-reduction reactions, all of which could provide an important step to the onset of dissociation necessary to create hydrocarbons in petroleum systems. Further understanding the effects of γ-radiation in hydrocarbons systems could lead to more information about the radiolytic processes that take place. This could eventually lead to further understanding of oil generation in organic-rich source beds.

Master of Science / Department of Geology / Matthew Totten / Due to their high resolution and established success rates, 3D seismic surveys have become one of the most important tools in many hydrocarbon exploration programs. Basic interpretation of seismic reflectors alone, however, may result in inaccurate predictions of subsurface geology. Historically, seismic attributes have played a particularly important role in the characterization of the lithological and petrophysical properties of hydrocarbon reservoirs in Kansas channel fill lithofacies. Integration of an analysis based on post-stack seismic attributes may drastically reduce the chances of drilling in unsuitable locations. Previous theses have focused on establishing a suitable 3D seismic attribute analysis workflow for use in the determination of hydrocarbon production potential in areas of Ness County, Kansas, USA (Abbas, 2009; Phillip, 2011). By applying a similar workflow in the analysis of additional 3D seismic and well log data obtained from a nearby area in Ness County, and comparing those results to existing borehole and production data, this study seeks to test the hypothesis that seismic attribute analysis is a crucial component in the delineation of heterogeneous reservoir stratigraphy in Kansas lithologies. Time-structure maps, in addition to time slices of several 3D seismic attributes including amplitude attenuation, acoustic impedance, and event continuity all seem to indicate that five previously drilled dry wells within the study area were outside the boundary of a meandering, Cherokee sandstone body of potential reservoir quality. Additionally, comparisons of the results of this research to previous studies conducted in Ness County have provided an opportunity to assess, and potentially contribute to, paleodepositional interpretations made through the utilization of a similar workflow (Raef et al., in press). The results of this study seem to support a broadly NE-SW trending meandering channel system, which is in agreement with the interpretations of Raef et al., and the findings of Ramaker (2009).

Master of Science / Department of Geology / Sambhudas Chaudhuri / Rare earth element (REE) concentrations were measured in a source (reference) clay Ca-smectite standard and in the roots, stems, and leaves of a species of poplar plant (Populus eugenei). The poplar plant was grown in the clay standard under controlled laboratory conditions during a period of about three months. REEs were shown to fractionate in the clay mineral and plant materials with greater fractionation observed in plant materials. The REE data provide insight into the process of weathering of clay minerals such as a Ca-bearing smectite and provide insight into the degradation of and the composition of clay minerals in the plant environment. The degradation process is not followed by significant interlayer ion exchange effect on remaining clay minerals in the root environment. REEs were found to be transported into complex forms, potentially as REE-carboxylic anion pair complexes. The plant materials in this study were in general heavy REE (HREE) enriched relative to the source clay minerals due to the complexation effect. The REE anomalies observed in this study, in addition to the Ce and Eu anomalies, may be explained by the selective uptake by the plant by an enzyme effect rather than due to the influence of oxidation-reduction. The enzyme influence was more evident in the REE distribution when compared among the plant organs. These REE characteristics described for the plants may eventually be incorporated with data from numerous other studies and also used as a guide in the assessment of the contribution of plant materials to dissolved REE content in surface water and groundwater.

Master of Science / Department of Geology / Kirsten Nicolaysen / The Kerguelen Archipelago and the submarine Northern Kerguelen Plateau consist primarily of basalt erupted by the intraplate Kerguelen hotspot. The exposed volcanic rocks are tholeiitic basalts (29 Ma) followed by lesser alkalic basalts, highly alkaline phonolites, and syenites (24 Ma). This study presents the mineralogy, isotopic and geochemical compositions of lavas (n=59) from a 650 m section exposed in the wall of a glacial valley at Trois Menestrels in the Kerguelen Archipelago. This basalt section, exposed south of the Cook Ice Cap and closest to the Raillier du Baty alkalic plutonic complex, is further south and west of previously studied basalts exposed on the Plateau Central. Results of 40Ar/39Ar dating show the Trois Menestrels lavas erupted approximately 25 Ma, approximately contemporaneously with other Plateau Central lavas and thus provide an opportunity to examine spatial compositional variations within the Kerguelen hotspot. Though the Trois Menestrels lavas are tholeiitic, The samples plot on the tholeiitic field at the stratigraphic section of Trois Menestrels, 80% of lavas from Mt. Tourmente are transitional to alkalic in the younger rocks (25.6 Ma). This sequence of tholeiitic to transitional to alkalic compositions is mirrored at Mt. Capitole and Mt. Marion Dufresne. Sr, Ba, Pb, Nb, Zr versus Nb plots show similar patterns across the Plateau Central and abundances overlap within error. Variations in isotopic composition reveal that Trois Menestrels is rather homogeneous compared to the other sections. A fundamental issue that derives from these results is the close relationship between these different rocks of the various region of the Plateau Central.

Master of Science / Department of Geology / Iris M. Totten / There have been numerous studies done during the past hundred years on ability grouping. The majority of research has focused on the elementary and secondary levels, with very little done at the post-secondary level of education. Research shows at the K-12 levels high achieving students have a greater level of learning when placed in groups together. Mid- level students also show higher achievement in homogeneous groupings. Both high and mid-level students benefit from heterogeneous grouping, but with smaller gains. Lower ability students placed in homogenous groups have shown significant gains, but still perform better when grouped heterogeneously compared with classes that are not grouped by ability. All students show increases in learning when placed in small groups of any kind. Mid-level and low achieving students have higher levels of learning when they are taught by someone determined to close the gap, who takes the students' abilities into consideration, and focuses on increasing those abilities. Unfortunately, this often does not happen, and when students are grouped by ability, the higher achieving students do well, and the rest fall further behind. This graduate research looks at the impact of skill grouping at the university level. Rather than separating students into different classes by ability, students were placed in purposeful groups within the class. Overall both homogeneous and heterogeneous groupings performed better than the control self-selected sections. One homogeneous quartile showed significant improvement in performance compared to the heterogeneously grouped students, but another homogeneous quartile showed a significant decline in scores. Gains in one subset of student should not come as a detriment to another subset of students, so homogeneous grouping is not recommended. Of the three grouping methods, only heterogeneous grouping showed significant increases in scores without harm to other students, and for this reason, this study recommends using a heterogeneous method of grouping students in future GEOL 103 classes.

Master of Science / Department of Geology / Allen W. Archer / Abstract This study compares the tidally influenced facies found within the Tonganoxie Sandstone Member (Stranger Formation, Douglas Group) (Upper Pennsylvanian) of northeastern Kansas with similar facies directly observed in the upper intertidal mudflats of Turnagain Arm of Cook Inlet (Alaska, USA). The two settings contain strikingly similar facies that are characteristic of upper macrotidal estuaries with a strong influence of tidal activities. Identical aspects and features found within both settings include rhythmic vertical variation in stratum thicknesses (cyclic tidal rhythmites), high estimated sedimentation and aggradation rates, and biogenic and physical sedimentary structures (e.g., drag marks, raindrop impressions, arthropod traces and tetrapod trackways, zigzag burrows, runoff washouts, and upright trees, among others). Tidal rhythmites are the most important evidence that is indicative of the tidal influence on the depositional processes of these two study areas. Such cyclic tidal rhythmites have been reported and described from several Carboniferous settings in the eastern USA. Modern analogs to these Carboniferous rhythmites are usually found within upper macrotidal estuarine depositional environments, especially within fluvio-estuarine transitional zones. These environments are distributed over a wide range of modern latitudes. Using cyclic tidal rhythmites as modern analogs for interpreting similar ancient facies is a powerful tool for paleogeographic and paleoenvironmental reconstructions, although it is somewhat a new approach.

Master of Science / Department of Geology / Iris M. Totten / Problem-based learning in the sciences has been demonstrated to be a successful educational approach to engage students and increase content knowledge. However, the power of collaborative learning to engage students, increase content knowledge and develop problem-solving skills in the sciences has not yet been fully researched. Collaborative learning has an enormous potential not only to foster student learning, but also to increase interest in the sciences and promote cutting-edge education strategies worldwide. Collaborative learning tactics in this study take place within the virtual learning environment entitled “GeoWorlds.” GeoWorlds is an online educational gaming program within the Second Life 3-D Teen Grid. The curriculum was developed as a collaborative, investigative and engaging program to promote learning of Earth science content. The program allows students to be submersed-in and explore different geologic time periods; enabling them to observe species and geological structures while interacting with one another to complete tasks. This study investigates the educational impact, emotional response and overall feedback of the GeoWorlds virtual learning environment on Midwest ninth graders.

Master of Science / Department of Geology / Allen W. Archer / Turnagain Arm is the hypertidal (commonly exceeding 9 m) west-east trending extension of Cook Inlet in south-central Alaska. The inlet formed from a drowned glacial valley that was subsequently filled with tidal deposits of silt and fine sand. The tidal system is semidiurnal with a prominent diurnal inequality. There are also variations due to spring and neap tides. Turnagain Arm is home to a tidal bore generated during spring tides that can reach heights of up to 2 m and travel at speeds of up to 5 m/s. Current reversals can be dramatic with ebb tidal velocities of 6 m/s changing to flood velocities of 10 m/s over a period of a few minutes. During the initial flood tide, highly turbid water can rise as fast as 10 cm/min. This combination of elements results in a highly dynamic depositional setting. Measurements taken in the inner estuary during several neap-spring cycles in the summers of 2007-08 documented deposition upon mud bars of as much as 8.9 cm per tidal event. Conversely, erosion of up to 13.5 cm per tidal event has been measured. The highest rates of deposition and erosion occurred during the spring tides while much lower rates occur during the neap tides. Some portions of the inner estuary are only submerged during the extreme high tides. The magnitude of the high tide needed to cover each site increases with increasing distance into the upper estuary. Even if submerged, deposition does not always occur. Such a high percentage of non-depositional events has real implications when interpreting tidal cyclicity of the rhythmites found at these sites.

Master of Science / Department of Geology / George R. Clark II / Conulariids are one of the most enigmatic groups of fossil organisms, and have been stimulating debates since the late 19th century. Many major questions remain; for example, three independent researchers (Babcock and Feldman, 1986b; Oliver and Coates, 1987; Van Iten, 1992b) reported three different mineralogies for the conulariid test within a six-year period, and are not known to have reached an agreement. Conulariid morphology is also debated, and many workers seem unable to agree on the basic architecture of the test or how it grows. Conulariid workers have also attempted to determine the taxonomic classification of conulariids, especially whether they have cnidarian affinities or occupy their own phylum. My work attempts to clarify some of these issues, as well as determine whether any morphological variation exists within single species of conulariids in different paleoenvironments. To this end, I have collected and prepared specimens for examination by scanning electron microscopy, transmitted polarized light microscopy, energy-dispersive spectrophotometery, and x-ray defractometry. Results include evidence for the presence of organic matrix in the conulariid test microstructure, the presence of three types of lamellae in the test, and support for carbonate-rich apatite [Ca5(PO4,CO3)3(OH,F)] mineralogy. Details of the test microstructure add further support for a coronatid scyphozoan affinity. The conulariid species examined here displayed no microstructural or mineralogical variation between different paleoenvironments (unless two of the species are actually environmental varieties, which seem unlikely).