EDUCATIONAL BENEFITS OF A LARGE WATER AND SEDIMENT RE-CIRCULATING FLUME FOR SEDIMENTARY GEOLOGY LESSONS

Introductory physical geology lessons on streams and sedimentary geology typically rely on sedimentary rocks, maps and computer models in a classroom setting. Upper level courses typically combine classroom studies with field studies in streams or rivers. Through the use of a large sediment and water re-circulating flume in-house at the University of Wisconsin-Milwaukee, students are presented some of the benefits of field studies of streams without leaving the building. The 10-meter long, glass-walled research flume, loaded with 15 tons of medium-sized sand, allows students the unique opportunity to study sediment erosion, transportation and deposition, and observe a ‘virtual cross section’ of a shallow stream. Unlike a natural stream, where the velocity is controlled by the stream gradient, channel characteristics and discharge, the stream velocity within the flume is controlled manually, using a variable speed, 30 horsepower turbine pump.

Students in a physical geology course are given the opportunity to operate the research flume to conduct three in-class experiments to evaluate the relationships among stream velocity, stream depth and stream bedforms. In one experiment, students use a flow meter at various depths to predict and observe the relationship between stream depth and stream velocity. Students also operate the turbine pump, to increase the re-circulating velocity, to observe and measure the changes in bedforms with increasing stream velocity. Students also study the observed relationship between stream depth and stream bedform along the length of the flume. Use of the research flume in an educational setting has yielded greater learning outcomes for lab lessons on sedimentary geology and streams. Review of student satisfaction surveys revealed the greatest ‘student satisfaction’ among all geology lessons in the physical geology lab setting.