THE FLOATING LITHOSPHERE -- A SET OF SPREADSHEET MODULES TO PROMOTE GEOLOGICAL NUMERACY

Courses in quantitative literacy (QL) or quantitative reasoning (QR) are being developed at numerous colleges and universities. A theme of these efforts is Math Across the Curriculum (MAC). MAC provides an opportunity to promote earth-science literacy (ESL) via Geological Numeracy, the intersection of QL (or QR) with geological content. We are developing geological-numeracy spreadsheet modules that enhance QL and ESL simultaneously. The various sets of modules feature benchmark issues that are appropriate for courses in the history of mathematics and/or science, as well as various QL/QR and geology courses. “The Floating Lithosphere”, on isostasy, consists of four PowerPoint/Excel modules. Each module is intended to engage students for 1-3 hours in a self-paced lab or homework environment. The first module explores geological hydrostatics in terms of pressures and depth of compensation. The second recasts the problem using buoyancy forces and the Archimedes Principle. The third focuses on the depth of compensation in the classic Woollard intercontinental cross section. The fourth adds gravity to the cross section, introducing free-air and Bouguer calculations via forward modeling. The modules emphasize weighted averages, logic functions, and rearranging equations to produce spreadsheet formulas. ESL concepts are pressure, buoyancy, gravity, and the visual image of mountain provinces with roots. Although the mathematics is not difficult, the higher-order thinking is challenging. We are seeking collaborators for classroom-testing and assessment of these and similar spreadsheet-based modules.