BIOGEOCHEMISTRY
Biogeochemistry analyzes the interactions between life and the chemical cycles in the Earth system. This is an inherently multidisciplinary endeavor, as it integrates the biological, chemical, geological, and physical sciences. Biogeochemists at Penn State (Arthur, Brantley, Fantle, Freeman, House, Keller, Kump, Macalady & Sowers) address fundamental questions spanning from the millisecond to millennia and from the molecular to the planetary scales. Example questions include:
- How do microbes affect mineral weathering?
- How can we decipher the information contained in marine sediments or ice cores?
- How have the biogeochemical cycles interacted with climatic change in the geological past and during the current anthropogenic perturbation?
- How can life survive in extreme environments that may be found on other planets?
We approach these questions in expeditions from the tropical oceans to the polar ice caps and by using techniques such as isotope mass spectroscopy, culture experiments, molecular methods, and computer modeling.
Learn more about Biogeochemistry at Penn State
ENVIROMENTAL GEOCHEMISTRY
Environmental geochemists at Penn State (Brantley, Heaney & Kubicki) investigate the kinetics and the atomic-scale mechanisms that govern mineral-fluid reactions at the Earth’s surface.
Examples of the kinds of problems that we study would include:
- adsorption and sequestration of inorganic and organic contaminants in soils and sediments
- aqueous complexation of metals with dissolved organic matter
- stable isotope fractionation between minerals and solutions
- dissolution and precipitation reactions of silica, feldspar, and metal (hydr)oxides.
We approach these issues by striving to combine molecular modeling techniques with synchrotron X-ray diffraction and spectroscopy in innovative ways.
CHEMISTRY AND PHYSICS OF ROCKS AND MINERALS
Several faculty in the Department of Geosciences work in the broad area of Physics and Chemistry of Rocks and Minerals. A primary focus is to unravel the mechanisms by which atomic-scale properties of Earth materials control large-scale geologic and geophysical processes.
Faculty in this area include Brantley, Fantle, Feineman, Furman, Heaney, Kubicki, Marone, Ohmoto, & Saffer. They are investigating the relationship between mineral chemistry, fluid-rock interactions and rock behavior using a variety of methods including:
- theoretical molecular modeling
- crystal structure analysis by synchrotron X-ray diffraction
- high resolution transmission electron microscopy
- reactive transport studies
- stable and radiogenic isotope analysis
- major and trace element microanalysis
- laboratory experiments at a range of pressures and temperatures
- novel fluid flow-through capabilities and chemistry
- mineral surface spectroscopy.
Geoscience Faculty work closely with Penn State Material Scientists and Geoenvironmental Engineers, and with the Materials Research Institute at Penn State, which features a wide array of state-of-the-art analytical instrumentation.
PETROLOGY AND VOLCANOLOGY
The Petrology and Volcanology group at Penn State (Feineman, Furman & LaFemina), explores the physical and chemical processes attendant to eruptive activity in a variety of tectonic settings, including active arcs, continental rifts and ocean islands. Their efforts integrate a range of techniques that encompass field work, SEM and TEM microanalysis, electron microscopy, image analysis, bulk rock analysis with DCP and ICP-MS, radiogenic isotope mass spectroscopy and direct low- and high-pressure experimentation.
Research in this area addresses fundamental questions that span a range of temporal and spatial scales, such as:
- What is the role of mantle plumes in continental rifting?
- How do melt segregation and transport processes affect eruptive geochemistry?
- What is the role of subducted fluids in arc magma genesis?
- How can major explosive eruptions be predicted more accurately?
Faculty use an interdisciplinary approach, collaborating closely with geophysicists, chemists and computer scientists both at Penn State and around the globe.