Moftah El Shawaihdi, graduate student at New Mexico Tech, will present the weekly Earth Science Seminar. His topic is "Geochronology, Petrology, and Stratigraphy of Neogene Units in the Sahabi Area, Northeastern Sirt Basin, Libya." Hosted by Dr. Peter Mozley and Brad Sion. Sponsored by the Earth and Environmental Science Department. 4 p.m. in MSEC 101.