Evaluating the use of seismic data for monitoring fluvial bedload transport

Rebecca Hodge, Emma Vann Jones, Jeff Warburton, Bishnu Sharma, Hal Voepel, Julian Leyland, David Sear
2016
Evaluating the use of seismic data for monitoring fluvial bedload transport
This is a Full Scientific Report resulting from NERC Geophysical Equipment Facility Loan 1026, principal investigator Dr Rebecca Hodge.

Abstract

Researchers have previously demonstrated correlations between seismic signals and fluvial processes (in particular discharge and bedload transport). This is an attractive finding because it suggests the possibility of an unobtrusive method to measure bedload transport. However, the range of rivers where this might work, the way in which seismic data might vary with channel type, and the strengths of any correlations between fluvial processes and seismic data are still unknown. We collected three sets of seismic data over 6 months adjacent to two different rivers (Trout Beck, a bedrockā€alluvial channel; and Bury Green Brook, an alluvial channel), along with concurrent discharge and bedload data. Initial analysis of the data suggests that the best correlation between seismic data and fluvial processes occurs in Trout Beck (seismometer TBU), where the seismometer was closely coupled to the bedrock that comprised the river channel. We identify dominant signals at 12 and 21 Hz; however, they are not caused exclusively by the discharge and bedload. The other seismometer at Trout Beck (TBU) was buried in mine waste, and fluvial processes are harder to identify in the noisier data. Data from Bury Green Brook (BGB) are dominated by diurnal signals, and require further processing before an assessment can be made.