Scientific results: We found that carbonate boundstones were datable, but that other sedimentary phases (marine and diagenetic cements) were far more reliable. We moved forward testing these phases in multiple stratigraphic successions worldwide, and constructed a database of published results comparing the depositional and measured U-Pb ages of carbonates globally. In multiple locations, we found that U-Pb ages of carbonates were consistent with depositional or early post-depositional processes, and identified previously under-discussed modes of failure for this geochronometer (scatter leading to erroneously too-old ages). We found that, on average, the measured U-Pb ages of sedimentary and diagenetic carbonate phases falls within <20 million years of its depositional age.Social impacts: In June 2022, Cantine taught an intensive seminar-style class to high school students in Mississippi, United States through the program Freedom Summer Collegiate. Mississippi has among the lowest-performing schools in the nation and students consistently face obstacles on the road to higher education. Freedom Summer Collegiate intervenes to provide talented high school students the opportunity to practice the critical thinking and learning skills they will need to succeed in a university setting. Cantine planned, programmed, and taught a 4-week long class that met daily for 70 minutes, and supported another teacher as a teaching assistant in a second class. The topic of Cantine’s class was physics and gravity, which allowed students to participate in classic active laboratory experiments including measuring the speeds of falling objects and designing a vehicle capable of protecting an egg from a 3-meter fall. Cantine drew on her prior three years of experience teaching with Freedom Summer Collegiate to deliver hands-on lessons that challenged students while providing them ample support. Seven students attended regularly and participated in class.
