2023-2024: Near-Surface Geophysics: Estella A. Atekwana

Estella A. Atekwana
University of California, Davis

Biography 

Estella Atekwana began her tenure as dean of the College of Letters and Science in August 2021. She provides academic and administrative leadership for the largest college on campus, overseeing 37 departments and academic programs with more than 900 faculty across the arts, humanities, social sciences, mathematical and physical sciences.

Atekwana is a renowned geophysicist whose research interests include biogeophysics, near surface geophysics, tectonics, geodynamics and continental rifting.

She previously served as dean at the University of Delaware’s College of Earth, Ocean and Environment and as head of the Boone Pickens School of Geology at Oklahoma State University. She also serves as a member of the governing board of Botswana International University of Science and Technology. She has a collaborative National Science Foundation project in Uganda to study the Albertine rift, and has received approximately $11.7 million in research funding, primarily from the U.S. Department of Energy, the NSF and industry.

She is a fellow of the Geological Society of America and a member and recipient of outstanding educator awards from the Association of Women Geoscientists and the Society of Exploration Geophysicists. Her contributions to exploration geophysics were recognized with the 2021 Reginald Fessenden Award from SEG, as well as the SEG 2020 Virtual Near Surface Global Lecturer award. She also belongs to the American Geophysical Union, the European Association of Geoscientists and Engineers, the Geochemical Society and the National Association of Black Geoscientists.

Atekwana received her bachelor’s and master’s degrees in geology from Howard University and her doctorate in geophysics from Dalhousie University, Nova Scotia, Canada.

Abstract: Biogeophysics: Geophysical Sensors for Biogeochemical Hotspots and the Search for Life

Microorganisms are found in almost every conceivable niche of the Earth from hydrothermal vents in the deep ocean basins to the cold subglacial lakes of Antarctic ice sheets to deep mines in South Africa. As such, microorganisms have played an important role in transforming Earth systems (e.g., accelerating mineral weathering), global climate change, and mediating different biogeochemical cycles over most of Earth’s 4 billion history. In-situ microbial-rock interactions are dynamic and occur at both temporal and spatial scales that prove difficult to investigate at resolutions needed to fully understand them, thus necessitating the need for the development of non-invasive tools/sensors to interrogate these processes. Interestingly, these microbial-rock interactions modulate changes in rock physical properties generating measurable geophysical signatures that can be recorded with conventional geophysical sensors (e.g., seismic, magnetics, electrical and electromagnetic).  The recognition of these microbial-catalyzed changes in geophysical signatures resulted in the development of Biogeophysics: the study of the physical changes in earth materials catalyzed by microorganisms that are observable with geophysical techniques, as an interdisciplinary field of study. In this presentation, I will provide examples of how geophysical sensors are used to sense subsurface microbial activity, from cell growth and biofilm formation to biomineralization and biogeochemical cycling of metals to the monitoring of microbial-induced natural attenuation of contaminants. Future directions such as the search for life on other planetary bodies will be explored.