Studying the sedimentary filling of an Alpine valley for intermediate geothermal energy

The feasibility of a geothermal project depends on the geological conditions of the targeted reservoir. For this purpose, 3 profiles were acquired across a broad Alpine valley to define the sedimentary structures and geometry of the bedrock.

This study was conducted in an urban context and called for a great investigation depth (800-1000m) which required the use of explosives to ensure a satisfactory signal/noise ratio.

The resulting sections provide unprecedented high-resolution data, in particular concerning observed fluviolacustrine structures. The bedrock geometry allowed us to clarify the goals of this geothermal project.

Reflection seismology is able to highlight geological interface in both quaternary units and bedrocks

The high resolution sections highlight small fluviolacustrine structures. Bedrock geometry is also very well illustrated.

Explosive are a perfect seismic source but are seldom used in inhabited areas
Location Switzerland
Instrument Geode
Geometry 96 geophones, 5m spacing
Positioning DGPS
Source Explosives
Length 6.9 kilometers
Personnel 7 people
Duration 10 days