Imaging the structure of solifluction lobes in the Garner Run Subcatchment of the Susquehanna Shale Hills Critical Zone Observatory using 2D Seismic Refraction Tomography
Abstract
Our research focuses on the Garner Run Subcatchment, located in the Susquehanna Shale Hills Critical Zone Observatory within Shavers Creek Watershed, Pennsylvania. The Garner Run Subcatchment is a sandstone landscape that shows evidence of periglacial features, such as solifluction lobes that formed during the Last Glacial Maximum. Using seismic refraction tomography, we imaged solifluction lobes to understand their structure. We collected data along four 236-m transects, three in the direction of sediment transport and one perpendicular. Data were collected with 4-m geophone spacing. The seismic refraction tomography images showed a thick layer of slow velocity materials upslope that thins out downslope. We hypothesize that the slow velocities correspond to the boulders deposited upslope and the higher velocities are indicative of finer sediments deposited downslope. This structure has implications for the local groundwater flow within the Garner Run Subcatchment. This research was performed as part of the GeoPATHS Near Surface Geophysics Field Experience, which engages freshman and sophomore undergraduate students, many who are non-geoscience majors from under-represented minority backgrounds, and teaches them about critical zone science and geophysics.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMNS21C0834C
- Keywords:
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- 0439 Ecosystems;
- structure and dynamics;
- BIOGEOSCIENCES;
- 1625 Geomorphology and weathering;
- GLOBAL CHANGE;
- 1829 Groundwater hydrology;
- HYDROLOGY;
- 1835 Hydrogeophysics;
- HYDROLOGY