Earth and Atmospheric Sciences

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Mineral Resources of Indiana: Road Materials
(State of Indiana Department of Conservation; Division of Geology, 1938) Fix, G.F.
Rock used for road construction in Indiana is obtained from glacial deposits of sand and gravel, from deposits of residual gravels, and from quarries in the bedrock formations. The glacial deposits include several different rock types, chiefly quartzites and granites, with gneiss, limestone, schist, and basic igneous rocks present in smaller quantities. They occur in irregular and discontinuous deposits along streams, and in moraines, oskers, and outwash plains, in the glaciated portions of the state.
Silurian and Devonian Formations in Southeastern Indiana
(Department of Geology, Indiana University, 1947) Esarey, Ralph E.; Malott, Clyde A.; Galloway, J.J.
The conference is planned to provide an opportunity to observe and discuss the outcrop sections of the Silurian and Devonian rocks in southeastern Indiana. The broad aspects of the stratigraphy and fauna will be emphasized since most persons attending will not be intimately familiar with these formations.
Theses Accepted for Graduate Degrees in Geology at Indiana University Since 1887
(Indiana University Department of Geology, 1960) Freeman, Ellen L.
Bibliography of theses accepted for graduate degrees in geology at Indiana University since 1887. The list consists of thesis titles obtained from two sources: 1) the file of thesis manuscripts (typewritten originals) in the Geology Department's Library, and 2) the commencement programs filed in the administrative offices of Indiana University.
Geological Sciences Indiana University
(Indiana University Department of Geological Sciences, 1972) Sciences, Geological
A department publication for the year 1972, describing required coursework, facilities and faculty.
A Behavioral Study of Locational Changes in Upper Class Residential Areas: The Detroit Example
(Department of Geography Indiana University Bloomington, Indiana, 1974) Backler, Alan L.
Geological Sciences Indiana University Bloomington, Indiana
(Indiana University Department of Geological Sciences, 1976) Sciences, Geological
A department publication for the year 1976, describing required coursework, facilities and faculty.
Geological Sciences Indiana University Bloomington, Indiana
(Department of Geological Sciences Indiana University, 1986) Sciences, Geological
A department publication for the year 1986, describing required coursework, facilities and faculty.
Workshop on Fossil Crinoids
(1989) Lane, N. Gary
The Workshop on Fossil Crinoids at the 28th International Geological Congress is designed to bring scientists interested in and engaged in studies of the Crinoidea together for loosely structured discussions of many aspects of morphology, evolution, and paleoecology of fossil crinoids.
History of the Indiana University Department of Geological Sciences: 1840-1997
(Department of Geological Sciences Indiana Universtiy, Bloomington, 1997) Lane, N. Gary
Study of the geological sciences at Indiana University has had a long and distinguished history. Beginning with the first lectures in 1840, the university has attracted and retained a series of outstanding teachers and research scientists who have consistently trained students to become able scientists in academics, government, and industry. The faculty and alumni of the Department of Geological Sciences can rightly be proud of their heritage at Indiana University. The department has fulfilled and continues to fulfill one of the roles of a state-supported institution--providing well-trained personnel to assist in the economic and educational advancement of the citizens of Indiana.
A Working Bibliography of Pre-1700 Literature on Fossil and Living Crinoids
(Department of Geological Sciences Indiana University Bloomington, Indiana, 1997) Lane, N. Gary; Ausich, William I.
This bibliography is presented to accompany our poster session on this topic at the national Geological Society of America in Salt Lake City. Readers should understand that the bibliography is not complete, that additional proofreading must be done, and that we have not been able to view and verify original copies of all of the references cited here.
History of the Indiana University Department of Geological Sciences: 1840-1997
(Department of Geological Sciences Indiana University, Bloomington, 1997) Lane, N. Gary
Study of the geological sciences at Indiana University Has had a long and distinguished history. Beginning with the first lectures in 1840, the university has attracted and retained a series of outstanding teachers and research scientists who have consistently trained students to become able scientists n academics, governments, and industry. The faculty and alumni of the Department of Geological Sciences can rightly be proud of their heritage at Indiana University. The department has fulfilled and continues to fulfill one of the roles of a state-supported institution--providing well-trained personnel to assist in the economic and educational advancement of the citizens of Indiana.
Stable Isotope Studies in Groundwater in the Northeastern United States and Associated Recharge of Glacial Meltwaters during the Last Glacial Maximum
(Thesis (Senior Honors)--Indiana University, Department of Geological Sciences, 2005-12-16) Brown, Kyle B.
Freshwater has been observed in confined aquifers extending over 100 km offshore from the northeastern coastal U.S.A., much greater distances than can be explained by groundwater models using contemporary hydrologic boundary conditions. In order to investigate the origin and residence times of these groundwaters, a total of 25 groundwater samples were collected on Nantucket Island and Martha’s Vineyard, MA, Long Island, NY, and along the coastal plain of southern New Jersey. Sample sites were believed to contain remnant glacial meltwaters of the LGM. Samples were analyzed for stable isotopes (18O, D) and major and minor ion chemistry. A U.S.G.S. monitoring well on Sandy Hook, N.J., had a chloride concentration of 15,151 mg/l. This well was determined to be intruded by saltwater. Observed groundwater δ18O and δD values were similar to those of modern meteoric waters in the recharge area. Other studies interested in LGM waters in Atlantic Coastal Plain aquifers have also found δ18O values representative of modern meteoric water. These studies used noble gases and 14C to confirm the presence of glacial age groundwater. Interestingly, their δ18O values did not correlate with colder recharge temperatures (~5°C cooler) as indicated by noble gas analyses. The absence of 18O-depleted groundwaters may be explained by (1) a poor correlation of δ18O to temperature along the Atlantic Coast, (2) conflicting effects of boundary conditions at the LGM (e.g. cooling accompanied by changes in atmospheric vapor origin or increases in evaporation), (3) sampling of modern Holocene waters believed to be LGM (4) inadequate sampling of aquifers. Future work will involve noble gas and 14C analyses of the groundwater samples. This will allow for the determination of recharge temperatures and groundwater ages, further building an understanding of the behavior of stable isotope values in the Atlantic Coastal Plain aquifer system.
Nitrogen loading of shallow groundwater aquifers in varying soil and topographic settings of southwestern Indiana
(2006-10-22) Reeder, Matthew D.; Olyphant, Greg A.; Letsinger, Sally L.
Numerous sources of nitrogen capable of impacting groundwater exist in rural areas of the midwestern United States. These sources include commercial and non-commercial fertilizers as well as on-site septic distribution systems. Over the past three years, we have undertaken detailed monitoring studies aimed at quantifying nitrate loading of shallow groundwater aquifers resulting from natural recharge at seven sites in southwestern Indiana. The sites occur in a variety of topographic settings and are associated with both well drained and poorly drained soils. Measured changes in soil-moisture profiles were used along with continuous measurements of precipitation and potential evapotranspiration to calculate the storage and movement of groundwater in the unsaturated zone. Nitrate loading of the shallow aquifers was then calculated by combining the flow rate with analytical data on solute chemistry from multiple depths within the unsaturated zone. The results of these calculations show that the highest loading rates occur at the study sites adjacent to agricultural fields treated with commercial and non-commercial (manure) fertilizers. The calculated nitrogen loading at these three sites ranged from 21 to as high as 136 kg of N per hectare (the highest loading rate occurred at the site where the manure was applied). In contrast, much lower loading rates were calculated using data collected from four sites associated with residential on-site septic distribution systems. In these cases, the calculated nitrogen loading values were an order of magnitude lower and ranged from 1.3 to 7.4 kg of N per hectare. These findings have implications for land-use management and have been used to guide the compilation of GIS-based maps that identify high- and low-risk areas throughout Indiana. This was accomplished by evaluating areas on the basis of soil characteristics and unsaturated zone thicknesses.
Compound Specific Carbon and Hydrogen Stable Isotope Ratios of Coalbed Gases in Southeastern Illinois Basin
(2007-01-12) Strapoc, Dariusz; Schimmelmann, Arndt; Mastalerz, Maria; Eble, Corland
Coalbed gases and waters from exploratory and production gas wells in the southeastern Illinois Basin were sampled to geochemically assess the origin of coalbed gases, with emphasis on Springfield and Seelyville coal members that are commercially targeted for coalbed methane production. On-line analyses of hydrocarbon gases (methane to butanes: C1, C2, C3, n-C4, i-C4) and CO2 yielded chemical concentrations, Delta-D, and Delta 13C values. The low thermal maturity of Indiana coals (vitrinite reflectance Ro ~ 0.6%) is in agreement with an overwhelmingly biogenic isotopic signature of coalbed gas that has greater than or equal to 96% methane generated via bacterial CO2-reduction. In contrast, thermogenic coalbed gas was generated by the stratigraphically equivalent coalbeds in western Kentucky’s Rough Creek Graben zone where higher maturities of up to Ro ~ 0.8% are reached due to tectonic and hydrothermal activity. No secondary biogenic methane was observed in Kentucky coalbed gases, probably due to greater burial depths and limited recharge of meteoric water. The two differently sourced types of coalbed gases are compositionally and isotopically distinct. Microbial biodegradation of thermogenic C2+ hydrocarbon gases in Indiana coalbeds preferentially targets C3 and introduces isotope fractionation whereby remaining C3 is enriched in heavy hydrogen and carbon isotopes.
Integrating Geophysical, Hydrochemical, and Hydrologic Data to Understand the Freshwater Resources on Nantucket Island, Massachusetts
(2007-05) Marksamer, Andee Jean
In this study we integrate geophysical, hydrologic, and salinity data to understand the present-day and paleo-hydrology of the Continental Shelf near Nantucket Island, Massachusetts. Time-domain electromagnetic (TDEM) soundings collected across Nantucket and observed salinity profiles from wells indicate that the saltwater/freshwater interface is at least 120 m below sea level in the northern and central portions of the island, far deeper than predicted (80 m) by modern sea level conditions. TDEM soundings also indicate that higher salinity conditions exist on the southern end of the island. These findings suggest a relatively high-permeability environment. Paradoxically, a deep, scientific borehole (USGS 6001) on Nantucket Island, sampling Tertiary and Cretaceous aquifers, is over-pressured by about 0.08 MPa (8 m excess head), which is suggestive of a relatively low-permeability environment. We constructed a series of two-dimensional, cross-sectional models of the paleohydrology of the Atlantic Continental Shelf near Nantucket to understand the flushing history and source of overpressure within this marine environment. We considered two mechanisms for the emplacement of freshwater: (1) meteoric recharge during sea level low stands; and (2) sub-ice-sheet and glacial-lake recharge during the last glacial maximum. Results indicate the sub-ice-sheet recharge from the Laurentide Ice Sheet was needed to account for the observed salinity/resistivity conditions and overpressures. Both TDEM soundings and model results indicate that a lateral transition from fresh to saltwater occurs near the southern terminus of the island due to ice sheet recharge. We also conclude that the overpressure beneath Nantucket represents, in part, “fossil pressure” associated with the last glacial maximum.
High resolution study of pyrite framboid distribution in varved Santa Barbara Basin sediments and implications for water-column oxygenation
(2007-05) Schieber, Juergen; Schimmelmann, Arndt
Monitoring of the concentration of dissolved elemental oxygen (i.e., ‘oxygenation’) of sub-sill waters in the Santa Barbara Basin (SBB) over the last few decades has consistently demonstrated sub-oxic bottom water conditions. However, anoxic conditions and hydrogen sulfide (H2S) are present below a few millimeters depth in the sedimentary column. The absence of euxinic conditions (i.e., anoxic-sulfidic: no free O2 but free H2S) in any part of the modern SBB water column makes this basin geochemically distinct from the Black Sea and other more oxygen-depleted basins. The varved sediment record from the central SBB has been used extensively for high-resolution paleoceanographic reconstructions. The SBB and other oxygen-depleted basins are considered modern analogs for black shales. Geochemical proxies for paleo-redox conditions in black shales need to be tested against modern, well-constrained depositional systems like the SBB. Pyrite framboids are a common component in many anoxic marine sediments and are deemed to carry paleoceanographic information. Observations from modern Black Sea sediment yielded the hypotheses that (i) abundant small framboids below 5 m diameter indicate euxinic (anoxic-sulfidic) bottom waters, and (ii) mean framboid sizes above 5m indicate suboxic or normally oxygenated bottom waters. We are using Scanning Electron Microscopy to compile a detailed inventory of framboid occurrence in AD 1983-2004 SBB varves and compare framboid size distribution against the known history of SBB water column oxygenation. Our ground-truthing effort has shown that framboids in modern SBB sediment dominantly are in the 2-4 m range and thus show closely similar size distributions to those measured in Black Sea sediments underlying an euxinic water column. Of course, the lower SBB water column is suboxic, and therefore we conclude that the framboid size distribution in modern sediment and in black shales has no diagnostic value for paleo-water column oxygenation. Our data further indicate significant variability in mean framboid size between successive varves that do not correlate with historic changes in SBB water oxygenation. We are evaluating other potential factors that could affect framboid size, for example (i) the availability of iron from clastic terrestrial input from the continent, (ii) the availability of freshly deposited organic matter nourishing the microbial community and influencing the redox profile near the sediment/water interface, and (iii) the depth of burial within the near-surface sediment that fosters the precipitation of framboids. The generally lower abundance of framboids in the youngest, uppermost varves suggests that it takes several years of mineralization before framboid formation goes to completion in a given sediment layer. After about 5 years framboid abundance appears to stabilize, providing further support to the view that framboids do not form in the water column and should not be considered recorders of water column oxygenation.
Sedimentology, Geochemistry and Paleobiology of a Marginal Marine Depositional Environment, the Mansfield Formation, Martin County, Indiana
(2007-05) Simonelli, Glenn
The Mansfield Formation of southwestern Indiana is comprised of varying sequences of mudstones, sandstones, shales, limestones and coals that date from the Pennsylvanian. Two outcrops in Martin County, Indiana, contain bedded and cross-bedded sandstones and laminated and friable siltstones, with a coal seam in one outcrop. Scouring, ripples and clay drapes are common in both outcrops. Carbon and sulfur analysis reveals total sulfur values consistently below 0.1wt.% and widely fluctuating C/S ratios. Trace fossils include Sclarituba isp., Treptichnus isp., Haplichnus isp., Skolithos isp. and tetrapod tracks. Roots and other plant material are common in some units. Palynological analyses of coal samples place the stratigraphically higher of the two outcrops to a position between the St. Meinrad and Blue Creek coals, thus dating the outcrop to the mid-Atokan. Collectively, the data point to a marginal marine depositional environment with brackish and freshwater fluvial influence and occasional sub-aerial exposure.
Improved On-line Measurement of Bone Collagen D/H as Forensic Environmental Indicator
(Isoscapes 2008 Conference, 2008-04-07) Topalov, Katarina; Schimmelmann, Arndt; Polly, David; Sauer, Peter E.
The organic hydrogen isotope ratio (deuterium/hydrogen or D/H) in the tissues of terrestrial organisms is related to D/H values of precursor hydrogen in diet and water from precipitation. D/H in (fossil) bone collagen potentially characterizes the (paleo)environment of an animal. However, the original (paleo)environmental isotopic signal of organic hydrogen is largely limited to carbon-linked hydrogen (C-H). In contrast, organic hydrogen that is chemically linked to other elements (e.g., oxygen O-H and nitrogen N-H) is more loosely bound and exchanges with ambient water, even during storage and sample preparation. Further, the fraction of exchangeable hydrogen in total hydrogen can vary among samples. The uncertainty from exchangeable hydrogen can be reduced via equilibration with isotopically known water vapors and subsequent mass-balance calculations arriving at the D/H of non-exchangeable hydrogen in collagen. Labor-intensive methods for isotopic equilibration of exchangeable organic hydrogen with water vapor have been used for more than 15 years. Here we present data from steam-equilibrated samples using a more efficient continuous-flow (i.e., on-line) approach using a ThermoFinnigan TC/EA fitted with an autosampler. Collagens from bones of modern White tail deer (Odocoileus virginianus) and Southern mule deer (O. hemionus) across climate gradients in the USA were prepared for our preliminary study. Traditionally, TC/EA samples are wrapped tightly in non-permeable silver capsules that limit the access of steam to collagen. Our samples were loaded into individual micro-perforated silver TC/EA cups. Cups were crimped shut and looked like small shopping bags. The perforations at the bottom of each cup were small enough that collagen could not spill out of the cup, but steam and gas could freely pass into and out of the cups. Steam equilibration of an entire carousel (up to 49 cups) in an equilibration chamber occurred overnight with isotopically known steam at 115ºC, followed by drying with dry nitrogen, cooling, rapid transfer of the carousel to the TC/EA, and determination of D/H. We present preliminary results from collagens and discuss advantages of the new method.
Stratigraphical Distribution of Crinoids and Blastoids in the Lower Carboniferous
(2008-06-03) Lane, N. Gary; Sevastopulo, George D.; Waters, Johnny A.
Stable silicon isotopes of groundwater, feldspars, and clay coatings in the Navajo Sandstone aquifer, Black Mesa, Arizona, USA
(Elsevier, 2009-02-14) Halliday, A. N.; Reynolds, B. C.; Zhu, Chen; Georg, R. B.
groundwater samples were from the Navajo Sandstone aquifer at Black Mesa, Arizona, USA, and the Si isotope composition of detrital feldspars and secondary clay coatings in the aquifer were also analyzed. Silicon isotope compositions were measured using high-resolution multi-collector inductively coupled mass spectrometry (HR-MC-ICP-MS) (Nu1700 & NuPlasma HR). The quartz dominated bulk rock and feldspar separates have similar d30Si of 0.09 ± 0.04&and 0.15 ± 0.04&(±95% SEM), respectively, and clay separates are isotopically lighter by up to 0.4& compared to the feldspars. From isotopic massbalance considerations, co-existing aqueous fluids should have d30Si values heavier than the primary silicates. Positive d30Si values were only found in the shallow aquifer, where Si isotopes are most likely fractionated during the dissolution of feldspars and subsequent formation of clay minerals. However, d30Si decreases along the flow path from 0.56& to 1.42&, representing the most negative dissolved Si isotope composition so far found for natural waters. We speculate that the enrichment in 28Si is due to dissolution of partly secondary clay minerals and low-temperature silcretes in the Navajo Sandstone. The discovery of the large range and systematic shifts of d30Si values along a groundwater flow path illustrates the potential utility of stable Si isotopes for deciphering the Si cycling in sedimentary basins, tracing fluid flow, and evaluating global Si cycle.

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