Location: 47.648, 8.753 (WGS84)
Reached drill depth: 253 m
Previous investigations:
- non-cored flush drilling (~205 m)
- 2D seismic survey by LIAG, ETH and University of Bern (2019)
Planed investigations:
- Core recovery (combined percussion/rotation drilling)
- Wire-line logging of drillhole
- Drill core analysis
The drill site BASA (yellow dot on map) will explore the overdeepened Basadingen Trough in Northeastern Switzerland. The Basadingen overdeeping formed during the Middle Pleistocene a valley that connected the Thur Valley in the South with the Rhine Valley in the North. The maximum sediment thickness is of up to 300 m south of the drill site. The seismic site survey revealed a multiphase infilling architecture with possibly two, partly crosscutting generations of erosion/sedimentation cycles. These likely represents different glacial erosion pulses of the western lobe of the Rhine Glacier.
The seismic site surveys reveal a multiphase stratigraphy showing a series of unconformities (colored lines). This internal architecture indicates that the trough was filled as a result of multiple glacial sequences (bold letters). The overdeepening reaches a maximum depth of ca. 300 m. The coring site (black) is located so that the drill core will recover a maximum number of sequences in well-layered facies including bedrock (Molasse, M), that is expected in ~250 m depth.