Geophysical methods for investigation and characterization of groundwater resources in buried valleys

摘要

Geophysical methods for the investigation and characterization of groundwater resources in porous media are shown using the subglacial Ellerbeker Rinne as an example. Five seismic sections illustrate the shape, internal structure and surrounding hydrostratigraphy of 25 km of this buried valley that, in some places, is more than 2 km wide. Data from the transient electromagnetic airborne survey reveal the distribution of electrical resistivity down to a depth of 300 m. The groundwater-saturated channel in the valley is clearly distinguishable from the Tertiary clays. A good and fast overview on the character of the confining beds down to 100 m depth was provided by the frequency-domain helicopter-borne electromagnetic method. A reliable interpretation was obtained by combining the different methods with borehole information and expert geological knowledge.