Richard Ash, Mike Evans, Vedran Lekić, Cecilia Sanders, and Nicholas Schmerr, University of Maryland
Faculty Lightning Talks
September 12, 2025 at 11:00 am (ESJ 0215)
Lightning-fast, 5-minute talks by 5 members of the Geology Faculty about their research.
Richard Ash — The UMD Plasma Lab and the Origin and Importance of Chondrites
Mike Evans — Common Era paleoclimate research emerging from a new database of databases
Ved Lekić — Topic TBD
Cecilia Sanders — The Geologic Record of Symbiosis and Community Resource Management (as told by A. Phosphorite)
Nick Schmerr — Planetary Geophysics: The Moon, Mars, and Beyond
Michael Kipp, Duke University
How precisely can we quantify oxygen levels in the ancient ocean?
September 19, 2025 at 11:00 am (ESJ 0215)
Reconstructing past changes in marine dissolved oxygen levels is critical for understanding Earth’s evolutionary history. It also allows us to use past events to guide our expectations for ocean chemistry under anthropogenic warming. In this talk, I will take a deep dive into the mechanics of what has rapidly become one of the most widely-used tools for estimating past ocean oxygen levels: the uranium isotopic composition of carbonate sediments. I will systematically review how this “paleo-redox proxy” works, moving from its calibration in the modern ocean to its quantitative underpinnings and finally to actual paleo-records from various archives. The talk will conclude with a preview of ongoing work to improve the rigor of statistical reconstructions from multi-proxy datasets.
Pupa Gilbert, University of Wisconsin, Madison
Biophysics of Biomineralization
September 26, 2025 at 11:00 am (ESJ 0215)
TBD
Matthew Jackson, University of California, Santa Barbara
TBD
October 10, 2025 at 11:00 am (ESJ 0215)
TBD
Admin Husic, Virginia Tech
TBD
October 17, 2025 at 11:00 am (ESJ 0215)
TBD
Austin Green, Virginia Tech
A Tale of Two Lithospheres: The Geodynamic Controls on the Habitability of Europa’s Subsurface Ocean
October 24, 2025 at 11:00 am (ESJ 0215)
Europa, the smallest of Jupiter’s four Galilean moons, harbors a 100-km deep ocean underneath its icy surface. Assessing the habitability (ability to support life) of this ocean is the overarching objective of NASA’s recently launched flagship mission Europa Clipper. Due to the ocean being entirely covered by ice, however, the hypothetical Europan biosphere cannot be supported by sunlight and by extension photosynthesis. Instead, chemotrophic life may be supported by the consistent delivery of nutrients into the ocean from both its overlying ice shell and underlying rocky/metallic mantle and core. These nutrients reside on Europa’s surface (oxidants) and within its mantle (reductants) and must be geodynamically conveyed through both icy and rocky lithospheres to the ocean by some means. In this talk, I will present my recent work on these geodynamic controls on ocean habitability in both the icy and the rocky layers of Europa’s interior. Salt infiltration may encourage weakening and densification of the surface ice lithosphere, causing it to collapse to the base of the shell, bringing these nutrients with it. The presence of volcanism on Europa’s seafloor will produce hydrothermal reductants to feed hydrothermal vent communities. Can the surface ice lithosphere overcome its rigidity and sink to the ocean? Can magma generated in Europa’s deep interior break through its rocky lithosphere to erupt on the seafloor?
David Williams, Arizona State University
TBD
October 31, 2025 at 11:00 am (ESJ 0215)
TBD
Jennifer Whitten, Smithsonian National Air and Space Museum
TBD
November 14, 2025 at 11:00 am (ESJ 0215)
TBD
Freya Morris, Hamilton College
TBD
November 21, 2025 at 11:00 am (ESJ 0215)
TBD
TBD
January 30, 2026 at 11:00 am (ESJ 0215)
Raquel Bryant, Wesleyan University
TBD
February 13, 2026 at 11:00 am (ESJ 0215)
TBD
TBD
February 20, 2026 at 11:00 am (ESJ 0215)
TBD
March 27, 2026 at 11:00 am (ESJ 0215)
Barabara Romanowicz, University of California, Berkeley
TBD
April 3, 2026 at 11:00 am (ESJ 0215)
TBD
Cole Nypaver, Smithsonian National Air and Space Museum
TBD
April 10, 2026 at 11:00 am (ESJ 0215)
TBD
TBD
April 17, 2026 at 11:00 am (ESJ 0215)
Elizabeth Niespolo, Princeton University
TBD
April 24, 2026 at 11:00 am (ESJ 0215)
TBD
The coordinator for the Colloquium Series is Dr. Cecilia Sanders.