Fall 2012 Colloquia

August 10: No colloquium, 1st day of classes

August 27: Zhexi Lu, University of Chicago. Title: Evolutionary Diversification of Mesozoic Mammals

Over the last two decades an unexpected new diversity of Mesozoic mammals have been discovered, ranging from squirrel-like gliding animals to beaver-like forms, completely overturning the textbook picture of mammals as tiny insectivores skulking around the nests of dinosaurs. Luo has been central in the discovery, description, and interpretation of many of the new finds.

September 3: Labor Day, no classes

September 10: Martin Appold, University of Missouri. Title: Solitary Waves and the Primary Hydrocarbon Migration Paradox: A Case Study of the Eugene Island Field, Gulf of Mexico Basin. Dr. Appold is a hydrogeologist by training and has recently conducted research into multiple areas such as modeling hydrocarbon flow, fluid flow and reaction-path modeling in the genesis of ore deposits sourced from meteoric water, and carbon dioxide sequestration.

Abstract: Hydrocarbons in the Eugene Island field, offshore Louisiana that are concentrated in Plio-Pleistocene sand reservoirs at depths from 0.5 to 3 km appear to have risen from older Tertiary source sediments at depths of at least 4.5 km at surprisingly high rates (up to 100’s of m/yr) given the low permeability of the intervening predominantly mud and shale sequence. Much of the hydrocarbon flow appears to have been channeled episodically along the Red growth fault, whose permeability is a sensitive function of fluid pressure. Strongly overpressured elastic porous media that possess such a permeability relationship are predicted from theory to generate solitary waves, which have the potential to transport pore fluids at rates much greater than expected from conventional Darcian mechanics.

September 11 Brown Bag Talk Dr. Martin Appold, University of Missouri. Title: Origin of Mississippi Valley-type Zn-Pb-Ba-F deposits in the Ozark and Interior Low Plateaus, U.S. Mid-continent

Abstract: Mississippi Valley-type (MVT) deposits have long been understood to be products of sedimentary basinal brines based on the bulk salinity, temperature, and major element composition of their fluid inclusions. Whether MVT mineralizing fluids resemble typical sedimentary brines with respect to ore metal content has until recently been far less certain. A further motivation for determining ore metal content in MVT mineralizing fluids is that ore metal content, together with pH, redox potential, and sulfur content, largely governs precipitation mechanism, which is also uncertain for many MVT deposits. Major element concentrations in MVT fluids reported in previous studies have largely been determined from bulk leachate analysis of fluid inclusions, where mixing of primary and secondary fluid inclusions and mineral matrix contributions are likely to have affected the reported results. Thus, another goal was to obtain improved measurements of major element concentrations, along with ore metal concentrations, through in situ analysis of individual fluid inclusions. These major element concentration data provide additional constraints on precipitation mechanism, fluid flow paths, and genetic relationships among deposits.

September 17: Chris Kelson, SUNY-Potsdam Title: Timing and Character of Mineralization Within Three Historic Mining Districts, North-Central Nevada

September 24: Elizabeth Hajek, Penn State University.

October 1: Sarah Spencer, AAPG Student Chapter, IUB. Title: Movie SWITCH and discussion.

October 8: Don Rimstide, Virginia Polytechnical Institute. Title: Mineral Stability in the Weathering Environment

October 15: Brooke Clements, President, Peregrine Diamonds Ltd.,Canada. Title: Discovery of Chidliak Diamond District, Nunavut, Canada

October 22: Professors Kathy Schick and Nicholas Toth, Department of Anthropology, Indiana University Title: The role of rock: Stone tools, human evolution, and prehistoric site formation

October 29: Ramesh Agarwal, Department of Mechanical Engineering and Materials Science Washington University in St. Louis Title: Numerical Simulation and Optimization of CO2 Sequestration in Saline Aquifers

November 5: No colloquium, GSA week

November 12: Steve Marshak, University of Illinois Title: The Origin of Map-View Curves in Fold-Thrust Belts

Abstract: The foreland fold-thrust belts of most mountain belts on Earth are sinuous in map view. Their structural trendlines, defined by the traces of folds, faults, and fabrics, form salients that and recesses (curves that are concave toward the foreland and convex toward the foreland, respectively). This talk will explore ideas used to explain the origin of such map-view curves, and the field and laboratory methods that have been used to study them. Results of the work emphasize that some curves form by oroclinal bending of once-straight orogens, while others initiate with a curved trajectory. New sandbox models, some using particle imagery velocimetry (PIV) is providing insight into how curves form in back-arc settings (the retrowedge of a bivergent thrust system), and how faults grow and evolve in fold-thrust belts.

November 19: No colloquium, Thanksgiving Break

November 26: Dan Soeder, Department of Energy. Title: Environmental Risk Assessment for Shale Gas Development

Dan Soeder

Dan Soeder is a geologist with the U.S. Department of Energy at the National Energy Technology Laboratory in Morgantown, West Virginia, where his interests include energy and environmental issues related to unconventional fossil energy resources. Prior to joining DOE in 2009, Mr. Soeder was a hydrologist with the U.S. Geological Survey in the mid-Atlantic region, after spending eight years on the Yucca Mountain Project in Nevada. His career before joining the USGS in 1991 included a decade of research at the Institute of Gas Technology in Chicago on unconventional natural gas resources, including shale, and several years characterizing drill cores on the DOE Eastern Gas Shales Project. Mr. Soeder received a BS degree in geology from Cleveland State University in 1976, and an MS in geology from Bowling Green State University (Ohio) in 1978.

Abstract: Research work begun in the 1970’s by the U.S. Department of Energy on the resource potential of Appalachian black shales helped lead to the development of these resources decades later. Gas production from shales like the Marcellus suggests that the ultimate recoverable reserves are enormous, and may, in fact, exceed all earlier estimates. Shale gas could free the United States from a decades-long dependence on imported oil, and it is abundant enough to replace nearly all coal combustion. Development of shale gas is not without environmental consequences, however. Two techniques employed to recover the gas in economic quantities are horizontal drilling and staged hydraulic fracturing, which create significant amounts of solid and liquid waste, and require relatively large work areas and infrastructure, affecting ecosystems, landscapes, air, and water. Rigorous scientific data on the environmental effects of shale gas development are sparse. The lack of information has contributed to a contentious public debate, and resulted in uneven regulations that are minimal in some locations and draconian in others. The U.S. Department of Energy, in cooperation with other federal and state agencies, is seeking a better understanding of the engineering risks of shale gas production. As such, researchers are collecting detailed scientific data on the possible effects of drilling and hydraulic fracturing on water resources, air quality, landscapes and ecosystems, and assessing the potential for induced seismicity. Concerns such as emissions, habitat fragmentation, ecological degradation, and contamination of surface streams and groundwater are being investigated by collecting baseline data near planned drill sites, and then monitoring changes in environmental parameters throughout the drilling and production process. Related field investigations on the potential direct effects of shale gas development on watersheds, drinking water aquifers, mobilization of stray gas, and lab studies on the chemistry of possible leachate from shale drill cuttings are either in the planning stages or underway. Scientific documentation of the environmental impacts from shale gas production is expected to help the gas industry develop and improve drilling management practices, identify sensitive environmental indicators for more focused regulatory monitoring, and provide accurate and unbiased risk information to citizens.

December 3: No colloquium, AGU week

December 10: Final Exam Week