Drilling Active Faults in South African Mines

This project is tied to the ICDP-DAFSAM project (Drilling Active Faults in South African Mines) and the NSF-funded NELSAM project (Natural Earthquake Laboratory in South African Mines).

It aims in quantification of the amount and composition of gases released from fluid reservoirs in rocks during seismic events. This will allow understanding their geochemical behaviour, their role as nutrient supply in stimulating microbial ecosystems in active fault zones and will enable us to model transport processes. In January 2007 at TauTona gold mine, SA, a mass spectrometer and an alpha spectrometer were installed at a 40 m long borehole at about 3.6 km depth. The borehole crosses the Pretorius Fault that is active as a result of the mining activities. The devices withdraw gases from the borehole and allow for long term gas monitoring in real-time. Except for some time-outs due to technical problems the system generated first data of exceptional quality.