Three-component BGK-3 borehole geophone and seven-component BGK-7 borehole geophone by Geotomographie are used in downhole seismic surveys. The borehole geophone is consisted of vertical and two horizontal (S-wave) components. Seismic recorder is Geode-24 by Geometrics.
We have a specifically manufactured source system for penetrating extreme depths.
Pickwin95 – Plotrefa