Indiana University Bloomington

Biogeochemistry

Biogeochemistry is a rapidly growing subdiscipline within the geological and environmental sciences. Research in biogeochemistry is inherently multidisciplinary, reflecting complex process at the intersection of biology, geology and chemistry .

Professor Lisa M. Pratt is Director of the NASA Astrobiology Team entitled Biosustaining Energy and Nutrient Cycles in the Deep Subsurface of Earth and Mars . Her collaborative research with Tullis Onstott (Princeton) on radiolysis of water as a source of subsurface energy for microbial growth has been highlighted by NSF under the caption Radiation Eaters. She has active field campaigns in arctic permafrost and in saline-alkaline lakes on the Oregon Basalt Plateau to study sulfate reducing and sulfide oxidizing microbial communities.

Graduate student Hui Jin uses a gas chromatograph to measure the chemical composition of natural gas that was desorbed from coal cores. Coalbed methane is a valuable natural resource in Indiana.

Deciphering and understanding biogeochemical processes and their evolution over geological time requires investigation of sedimentary records that preserve chemical clues of biological activity. Professor Simon Brassell explores the characteristics, abundances, and isotopic compositions of discrete molecules – biomarkers– as tools for assessment of microbial communities and processes, biological productivity, and episodes of perturbations of the carbon cycle related to environmental and evolutionary change, and as paleoclimate proxies.

Graduate student Melanie Everett prepares samples for oxygen isotopic analysis using the gasbench peripheral of a Delta Plus XP stable isotope mass-spectrometer.

Stable isotopes of hydrogen, carbon, nitrogen and oxygen in organic materials are used by Arndt Schimmelmann to understand which environmental conditions lead to certain stable isotopic signatures in modern biological materials and in fossils (for example, bones). Some of Schimmelmann's research requires oceanographic cruises to collect marine organic matter from the water column and from sediments. Similar isotopic techniques are applied to characterize the origin and thermal maturation of coal, petroleum and natural gas.

Peter Sauer uses tree-rings and sediments from lakes and oceans to study paleoclimate. He uses organic biomarkers and stable isotope ratios of carbon, nitrogen, and hydrogen to develop proxies of past environmental conditions. His projects range from late Paleozoic paleoceanography to late Holocene climate variability and the detection of anthropogenic climate change.

Dr. Peter Sauer and graduate student Katarina Topalov transfer a carousel holding samples for an elemental analyzer that is connected online to a Delta Plus XP stable isotope mass-spectrometer.

Our state-of-the-art instrumentation can be viewed on an illustrated tour of the Biogeochemical Laboratories. Contact our technical and administrative support staff about questions relating to the use of our facilities. Read about current graduate students and post-docs and their research projects, and about recent graduates and the titles of their theses. A list of selected recent publications is available as well as some recently published abstracts.

Email: Ruth Droppo
Phone: 812-855-0154
Fax: 812-855-7961

Biogeochemical Laboratories
Department of Geological Sciences
Indiana University
1001 East Tenth Street
Bloomington, IN 47405-1405
U.S.A.