Restricted to Jackson School of Geosciences majors. Field observation of geological processes and study of the mineralogy, petrology, stratigraphy, paleontology, and structural geology of central Texas. Two lecture hours and three laboratory hours a week for one semester, and six weekend field trips. Geological Sciences 420K and 320L may not both be counted. Prerequisite: For general geology majors: Geological Sciences 416K and 416M with a grade of at least C- in each, and credit or registration in Geological Sciences 426P with a grade of at least C-. For others: Geological Sciences 416K and 416M with a grade of at least C- in each.