Dr. Erin DiMaggio
College: College of Earth and Mineral Sciences
Address: 308 Deike Building
Geochemistry of volcanic ash in Afar, Ethiopia
Explosive volcanic eruptions produce volcanic ash (tephra) deposits that form marker beds (visible white/gray/black layers) in sedimentary rocks that are important for linking fossil, artifact, and rock records. Analyzing the geochemistry of glass shards (geochemical fingerprinting) is one method that allows us to link volcanic ash layers and has traditionally been accomplished using major element data collected on an electron microprobe. However, recent improvements to laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) methodology allows minor and trace elements of small (20μm) discrete, glass shards to be analyzed thus increasing the database for correlation studies.
Students working on this project will analyze volcanic ash samples collected from the Ledi-Geraru paleontological site in Afar, Ethiopia where the earliest fossil of the genus Homo was recently discovered. You will learn how to prepare samples for analysis, collect data using the LA-ICP-MS, process the data, and assess potential correlations that will significantly improve the geology and dating of the Ledi-Geraru paleontological site.