INTEGRATING STUDENT-LED RESEARCH IN ENVIRONMENTAL GEOLOGY INTO TRADITIONAL FIELD COURSES: A CASE STUDY FROM JAMES MADISON UNIVERSITY'S FIELD COURSE IN IRELAND

The ability to produce and interpret geologic maps is one of the primary goals of many field courses; however, very few geology graduates will pursue mapping as their profession. Those graduates who stay in the geosciences will most likely be employed in the environmental geology fields, and will be asked to formulate and test hypotheses as part of their profession. These trends have led many geology field camps to supplement their traditional bedrock mapping programs with exercises in applied geology, including the areas of geomorphology, geophysics, and aqueous chemistry. The James Madison University Geology Field Course in Ireland has in the past two years dedicated one week of the course to developing and testing hypotheses in environmental geology via student-led research teams working in conjunction with a faculty mentor. The case highlighted here is from the Carrownisky River in County Mayo, Ireland where contemporary issues in fluvial geomorphology were investigated. The goal of the students' research was to investigate topographic controls on sand deposition, point bar formation, and channel incision and how this would in turn affect the occurrence of alluvial gold deposits. Results indicated that fine sediment deposition in this high energy river system was limited to subsurface and over-bank deposits, and thus were not easily observable on the streambed. Point bar formations provided the most abundant and accessible supply of in-stream fine sediment. Students identified the upstream extent of point bar formation in the channel network as being limited by channel slope. At the downstream extent, point bar formation was inhibited by channel incision into thick cohesive sediment deposited in a former lake bed. These cohesive streambanks prevented lateral migration of the channel, thus restricting channel width and the space necessary for bar formation. In the reach where point bars formed, planform curvature was correlated with bar volume. Thus, high angle bends in the river were associated with large point bars that stored an abundance of fine sediment beneath the surficial armor layer. The combined understanding gained from this data-rich investigation provides important insight into river morphology and an effective mechanism for teaching hypothesis-driven research in geoscience field courses.