The Center also includes the expertise of the participating board members, their laboratory members, center personnel, and users.  The idea is to bring together scientists with stable isotope expertise that represent a broad spectrum of environmental science disciplines. This group includes center director Danny Rye, Karl Turekian, Mark Pagani, Ruth Blake, Hagit Affek, and Zhengrong Wang from the Department of Geology and Geophysics; David Post from the Department of Ecology and Evolutionary Biology; Gaboury Benoit and Peter Raymond from the School of Forestry and Evironmental Studies; as well as laboratory manager Gerard Olack and lab assistant Dominic Colosi.

The board combines to give the facility representation from geochemistry, bio-geochemistry, paleo-ecology, ecology, microbiology, and forestry. We also will have close ties to anthropology, engineering and chemistry. Below is a brief description of their research interests with regards to stable isotope analyses.

Isotope geochemistry related to ore deposits, metamorphic rocks, and paleoenvironments. The general research approach is to carry outintegrated studies that include stable isotope, radiogenic isotope, petrologic,mineralogical, chemical, and field data. The field data provides geologicconstraints. The stable isotope data (the isotopes of oxygen, carbon, hydrogen,sulfur, and nitrogen) are used to trace the fluid behavior. The radiogenicisotopes are used to trace the source of metals. The petrologic, mineralogical,and chemical data are used to put constraints on the temperature and pressurehistory of the rocks and fluids. The petrologic, chemical, and radiogenicisotope data are used to quantify the elemental mobility that took place in ahydrothermal or metamorphic system.

For the past several years a primary focus of my research has been the characterization and interpretation of O isotope fractionations in the PO4-water system during biogeochemical cycling of P in natural waters and sediments. A major area of current research surrounds characterization and "ground-truthing" of 18O/16O ratios ( 18O) signatures of phosphates in mid-ocean ridge (MOR) hydrothermal Fe-oxide deposits, with the goal of identifying reliable 18Op biosignatures and isotopic tracers of microbial activity and P cycling at MOR's, in Earth's deep biosphere, Mars and beyond. Many of the activities in my laboratory are devoted to development of methods for extraction and O isotopic analysis of PO4 (18O/16O and 17O/16O) in a range of geologic, biologic and extraterrestrial materials including deep-sea sediments, ancient rocks; biomass, and Martian soil analogue materials. A second area of major research is the O and S isotope behavior of sulfate during microbial S cycling in marine sediments (D'Hondt et al., 2004; Blake et al., 2005, Boettcher et al., 2005).

Paleoclimatology, paleoceanography, evolution of atmospheric carbon dioxide, organic geochemistry, biogeochemistry. My research primarily applies isotopic compositions and abundances of organic molecules (biomarkers), and records of stable isotope- and trace-element compositions of species-specific foraminifera to constrain the physical and environmental conditions of ancient oceans, terrestrial systems, and the atmosphere. My current interest and work is focused on understanding the factors driving Cenozoic climates.#259500

The use of radioactive and radiogenic nuclides in deciphering the environmental history of Earth. Also, studies on oxygen isotope signatures preserved in seawater phosphate and phosphatic deposits such as fish debris provide information on the sites of enzymatic equilibration in the water column, and consequently paleothermometry of ancient marine fish habitats.

Center Affiliates:

We study a variety of questions, typically within a food-web framework, in lakes, streams, and estuaries. Although we primarily work in aquatic systems, we also study interactions and processes that link aquatic and terrestrial ecosystems. The research on food-chain length was made possible by recent advances in stable isotope analysis. In addition to using stable isotopes to document food web structure, we are using stable isotope techniques to evaluate the flux of carbon into and through lake food webs. we plan to develop and apply compound specific stable isotope techniques to help better resolve food web structure in an effort to critically test a number of basic questions in food web ecology.

My research investigates the sources, distribution, speciation, transport, behavior, and fate of trace metals in freshwater environments. This work emphasizes field investigations in order to encompass and examine the full range of environmentally-relevant processes that influence metal cycling at a range of temporal and spatial scales. All components of watersheds are investigated, from soils and rivers, to lakes and sediments, but the water column is studied most because this is where our understanding is currently weakest. As the ultimate recipient of metals exported from terrestrial watersheds, estuaries are included, but freshwater environments are emphasized, since they have received much less attention in the past. Understanding metal behavior is important not only because of their biological significance (as possible toxicants or micronutrients), but also because they can serve to trace a range of environmentally important processes, thereby revealing information about how ecosystems function. This work helps to close a serious data gap, since contamination artifacts (caused by inadequate use of clean techniques) have compromised most of the past (pre-1990) data record on trace metals in fresh waters.

My main research emphasis is on the carbon budget of natural systems. I utilize the stable (13C) and radio (14C) isotopes of carbon to elucidate the sources and sinks of organic and inorganic carbon, in order to understand the role of rivers, estuaries and coastal systems in regional and global carbon budgets. This research provides fundamental information on the residence time and turnover times of riverine, terrestrial, and oceanic organic matter pools.