Sedimentological studies of western swiss lakes with high-resolution reflection seismic and amphibious GPR profiling

Continuous onshore/offshore (amphibious) GPR, offshore high-resolution reflection seismic (HRS) and stratigraphic methods are integrated for establishing or refining lake-level curves in western Switzerland. Initial results show that continuous GPR reflections are up to 5 m deep, inclined towards the lake center and traceable from onshore to offshore in some places. Due to their similar vertical resolution, GPR and HRS reflections can be positively correlated in some shallow (< 5 m) water areas. In general, the best seismic data are acquired from deep-water, fine-grained zones, whereas most radar data are largely obtained from littoral, coarse-grained zones. Calibration of all geophysical data comprises the analysis of archaeological excavations and existing/future borehole data.