2004 Denver Annual Meeting (November 7–10, 2004)

Paper No. 11
Presentation Time: 4:00 PM


POTTER Jr, Noel, Department of Geology, Dickinson College, Carlisle, PA 17013, pottern@dickinson.edu

Most geomorphic change, except during catastrophic events, is not obvious to the casual observer. Long-term observation of many geomorphic processes by student/faculty teams can engage students in research with multiple benefits. These benefits include: 1) results clearly show geomorphic change over years or decades, 2) the results give useful examples of local phenomena for both introductory and advanced courses, and 3) students learn diverse methods of data collection and analysis, sources of error in measurement, presentation of results, and that they must leave a careful record of results to be built upon by a new generation of student.

Examples used to illustrate these benefits include results of eleven surveys of transverse profiles of migrating creek meanders over 30 years, and weathering of sawed cubes of local limestone measured yearly over 15 years. The meanders have migrated as much as 3.5 m in 30 years and the limestone cubes, with an average weight of about 175 g, have lost nearly 3 g in 15 years. Results can be analyzed at various levels. For example, for the weathering limestone, students in an introductory course might be asked how long it would take for cubes of a given weight to weather away, given the weight loss per year. But the cubes clearly will decline in surface area over time, so for an advanced class, one might use dimensions, surface area, and density to determine a “bare rock” denudation rate that can be applied to long-term evolution of the local landscape.

Similar projects might be applied to: 1) beach profiles, 2) accumulation of sediment in deltas in lakes or farm ponds, 3) migration of eolian dunes, 4) sediment yield from construction sites, 5) mass movement such as soil creep and slumps, 6) weathering in road cuts through photography, and 7) stream sediment yield. Starting a project is the most difficult part, for one must wait a year or two for some results. But once some results are obtained and a data set grows, the incentive to continue increases. Make plans now. Start a project. The rewards are substantial.