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Ground Penetrating Radar Applications in Seismic Microzonation
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, Near Surface Geoscience 2015 - 21st European Meeting of Environmental and Engineering Geophysics, Sep 2015, Volume 2015, p.1 - 5
Abstract
The work presents a methodology that combines a first GPR survey and a subsequent measurement of seismic ambient noise vibration. The GPR signal characteristics used in this analysis are two: the amplitude of the background noise in the A-scans, and the frequency content of the received signal. The background noise could be consequence of three main sources: clutter as consequence of external reflections, electronic noise and energy randomly scattered in the medium. The first source could be identify in the GPR B-scans and usually produce anomalies similar to those caused by reflections in the targets inside the medium. The second source produce a continuous noise in the A-scans characterized because the average value is approximately constant. The third source introduces noise in the A-scans but its amplitude depends on the randomly backscattered energy. As consequence, the amplitude of this noise could be used in order to identify sudden changes in the shallow geology, always depending on the grain size distribution. The frequency content depends strongly on the water content. The analysis of the spectrum, combined with the analysis of the B-scans and the backscattering noise in the A-scans could be used in order to locate active subterranean streams.