MICROBIAL GEOBIOLOGY AND BIOGEOCHEMISTRY
The Department of Geosciences has excellence in isotopic biogeochemistry, organic geochemistry, and geomicrobiology. Current biogeochemistry research (Freeman, Ingalls, Lloyd, Lau) includes isotopic and geochemical signatures of photosynthesis, past climate, and microbial processes. Our geomicrobiology laboratories (House and Macalady) have on-going research that includes marine and terrestrial microbiology, microbial life in subsurface environments, and microbial life in extreme environments.
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 (Brantley, Fantle, Freeman, House, Ingalls, Kelley, Kump, Lau, Lloyd, & Macalady) 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 and precipitation?
- 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 and the dual-title program for Ph.D. students.
ASTROBIOLOGY
A major research focus of astrobiology is enabling the recognition of signatures of life on the early Earth, in extreme environments, and in extraterrestrial settings.
The Geosciences Astrobiology group (Brantley, Fantle, Freeman, House, Kump, Lau, Ingalls, Lloyd, & Macalady) develops novel approaches to detecting and characterizing life, investigate biosignatures in mission-relevant ecosystems and ancient rock and evaluate the potential for biosignatures in extraterrestrial settings.
The Penn State Astrobiology Research Center was created in 1998 as part of the NASA Astrobiology Institute (NAI). Those involved with the center work on understanding the connections between life and the evolution of our planet and the factors which influence the habitability of a planet over time, as well as biosignatures at all scales, from individual cells to the composition of planetary atmospheres.
Learn more about the Astrobiology dual-title program.
WHO WE ARE
Learn more about our faculty and research groups:
Dr. Susan L. Brantley works with students to understand the rates of weathering and transformation of rock into soil at all spatial and temporal scales. She is also interested in understanding how humans impact water quality.
Dr. Matthew Fantle's research group utilizes novel metal isotopes, in conjunction with traditional isotopic systems, aqueous geochemistry, and various modeling techniques to develop new proxies, understand diagenesis at a process level, and interpret geochemical records of the past. Over the years, the Fantle group has contributed to characterizing the isotopic composition of fluxes in the geochemical cycles of a range of elements, including Ca, Fe, Mg, Li, and Sr, constraining the rates and impacts of carbonate diagenesis using isotopic tools, quantifying the impact of microbes on mineral isotopic composition, and investigating hyperthermal events in the rock record.
Dr. Kate Freeman’s research group studies organic molecules and their stable isotope signatures. We use fossil molecules, or biomarkers, derived from plants, microbes, and algae, to study Earth’s climate history, including biogeochemical cycling of carbon and other life-sustaining elements in the ancient atmosphere and oceans, and the patterns of water, vegetation, and fire on ancient landscapes. Our group currently has a focus on new ways to measure isotopes within organic molecules (isotopologues) for biogeochemical and astrobiological applications and for space exploration. Kate is Director of the NASA Astrobiology Center for Isotopologue Research (ACIR) at Penn State, and is a participating scientist on NASA’s OSIRIS-REx mission. She is co-Director of the International Geobiology Course supported by the Agouron Institute and the Simons Foundation.
Dr. Christopher H. House and his research group study the geochemistry produced by microorganisms and the evolution of microorganisms over the long history of the Earth. The work helps inform the search for life in the Solar System through the development of possible biosignatures. Dr. House also studies the geochemistry of Mars and other Solar System bodies, including the large variation of isotopic values found on other worlds with an aim of establishing how life might be detected. Similarly, research into the chemical origins of life aims to both advance our understanding of life’s beginnings here on Earth, but also inform how to detect life when it is potentially different than found on the modern Earth.
Dr. Miquela Ingalls and her research team use field geology in modern and ancient environments, petrography, and stable isotope geochemistry to reconstruct the conditions (temperature, nutrient availability, hydroclimate) under which life evolved throughout Earth history, and how microbes influence the carbonate rock record. Ingalls currently serves on the Executive Committee for the Biogeochemistry program.
Dr. Brian Kelley investigates the co-evolution of Earth environment and life through the integration of sedimentology, paleobiology, geochronology, and geochemistry. He specifically focuses on ancient intervals of rapid climate warming to better understand fundamental Earth system processes and the potential consequences of anthropogenic climate change.
Dr. Lee Kump and his group focus on modern and ancient biosphere transitions: temporal transitions like the rise of atmospheric oxygen, mass extinctions and global warming events, and spatial transitions: modern stratified ecosystems in marine and lacustrine settings.
Dr. Kimberly Lau’s group uses the geochemistry of sedimentary rocks to understand biogeochemical and Earth system change. Integrating field, analytical, and modeling approaches across spatial scales, this work aims to improve interpretation of geochemical (including isotopic) proxies in carbonate and siliciclastic rocks. Additionally, research in our lab aims to understand fluid-rock interactions in the context of early diagenesis and in geochemical cycles (i.e., nutrients, continental weathering).
Dr. Jenn Macalady’s group is focused on understanding interactions between microbes and planetary materials (rocks, water, gasses), and on understanding the limits to microbial life.
Dr. Max Lloyd’s group uses isotope geochemistry analyses to constrain interactions between life and Earth. We focus on the development and application of new isotopic measurements in organic molecules, especially isotopologue analyses (position-specific and clumped isotopes). Our geoscience questions are broad in scope, but we’re actively working on: i) plant-climate interactions, ii) deep biosphere microbial activity, and iii) the formation and alteration of organic molecules in space.
GEOBIOLOGY
We are offering for the first time an International Geobiology Course (IGC). An immersive and interdisciplinary course that explores how microbial life and the Earth have shaped each other. The IGC features immersive training in geobiology based on field experiences in central Italy and at Green Lake, NY. Students will be instructed by and get to know leading scholars, and will gain hands-on experience using world-class geochemistry, biology, and materials research facilities on the Penn State campus. Students will explore cave-forming microbial ecosystems, biosignatures in modern and ancient thermal springs, anaerobic phototrophy, how biology shapes carbonate sedimentation and marine platforms, and biogeochemical responses to catastrophic impacts and climate upheavals. Student will gain experience with state-of-the-art metagenomic methods, isotopic analyses, lipid and pigment biomarkers, imaging spectroscopy, microscopy, field methods, and computational and data analytical methods.
Learn more and how to apply: geobio@psu.edu (google.com).