ON THE MERIT OF HANDS-ON EDUCATION: IMAGING A BURIED OLD STREAM CHANNEL IN A SHALLOW ALLUVIAL FLOODPLAIN USING NEAR-SURFACE GEOPHYSICS

This research is one demonstration of the merit of hands-on education emphasized in the department of Geography and Earth Science at Shippensburg University. It reports the results of hands-on exposure of a M.S. student to near-surface geophysical methods. A geophysical investigation was conducted in the floodplain of the Burd Run, a small stream that runs through part of Shippensburg University campus in Pennsylvania. The goal was to detect the course of an old stream channel that was buried during a stream restoration project in 2002. Around 1937, a section of the Burd Run channel was straightened in order to use its full floodplain for pasture. The straightening caused roughly 1200 feet (~ 366 m) of slope failure. In 2002, the stream was restored to its original meandering course and the straightened segment was filled in. It was this filled-in channel that was the subject of this exercise. Two complementary geophysical methods were used; electrical resistivity (ER) and electromagnetic induction (EM). 2-dimensional interpretation of the ER survey showed areas of low resistivity consistent with the location of the buried channel. Similarly, the EM method produced high conductivity anomalies in the area of the buried channel. Thus, the two methods successfully detected the buried channel. The understanding gained from this study strongly demonstrates the merit of outdoor, hands-on education.