CAREER: To see a world in a grain of sand: Novel applications of sand grains as records of ancient surface environments

Sedimentary rocks preserve a record of how ancient ecosystems and environments responded to changes in climate, integrating over durations much longer than human lifetimes. This information provides a useful perspective on how modern ecosystems might be affected by climate change. This project will develop a new set of tools to estimate the amount of CO2 that was present in Earth’s ancient atmosphere based on the characteristics of a unique type of sand grain, which will improve our understanding of Earth’s past climate states. This research effort will be integrated with an educational project that will develop new inquiry-based teaching materials and curriculum to improve the Earth science education for K-12 students in Colorado, while also providing professional development opportunities to local school teachers and undergraduate students. This project seeks to expand the scope of paleoenvironmental information sedimentologists can glean from the rock record. This work will build upon the PI’s novel approach for reconstructing the carbonate mineral saturation state of ancient waters to address the primary research objective: to build and share a toolkit for applying ooid size measurements to reconstruct the carbonate chemistry of ancient waters and ancient pCO2 that will be widely useful to the scientific community. This objective will be accomplished by (1) creating a standardized and reproducible workflow for measuring and interpreting ooid size data, and (2) expanding the utility of this proxy by assembling a large suite of ooid size data from Cenozoic carbonate-producing lakes in the western US to test and refine the application of ooid size as a pCO2 constraint. The education and outreach component of this project will design, test, and share an educational platform consisting of a virtual and physical “Sand Library” paired with inquiry-based curriculum to improve Earth science education across a range of educational levels by illuminating the connections between the characteristics of sand grains and Earth surface processes. Sand Library development will be in partnership with a local Title I STEM magnet school and will engage with students in classrooms, provide professional development to school teachers, and facilitate opportunities for STEM enrichment outside of the classroom. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.