FROM FARMLAND TO BOOMING METROPOLIS: DEPOSITIONAL HISTORY OF A PIEDMONT POND IN RESPONSE TO URBANIZATION, CHARLOTTE NC

A multi-week laboratory exercise in the GEOL 3124 Sedimentology course at UNC-Charlotte comprises the analysis of the sedimentary history of a 0.8 hectare (2 acre) pond on campus property. The pond watershed has experienced changes in land use over 50 years that can be documented using property records, aerial photography and sedimentological analysis. The laboratory exercise includes the tasks of mapping the watershed, surveying coring locations, coring, core description, preparing bathymetric profiles and stratigraphic cross-sections, and composing a scientific report of the sedimentary history of the pond. Students gain experience with field techniques such as reading topographic maps, land use mapping, triangulation and sediment coring, and with laboratory techniques such as core description, facies correlation, x-ray diffraction and grain size analysis. Rather than learning those skills in discrete lab exercises, each effort contributes to the goal of understanding the sedimentary history of the pond. Furthermore, the report is prepared in stages (outline, rough draft and final draft) so that students receive feedback on how to prepare an illustrated scientific report. The students found that the pond experienced slow, organic-rich sedimentation when the watershed was vegetated, but that sedimentation rates temporarily increased due to construction of a nearby hospital.