During the last ten years, BRGM has carried out five experiments to chemically monitor drilling fluids. It has therefore developed a methodology adapted specifically to this type of work and has acquired considerable experience in the interpretation of the results. The results of these scientific investigations could find industrial applications. The purpose of this paper is to describe the evolution of the techniques employed and the principal results acquired during the period over which the work was carried out.
Drilling is fundamental to oil, mineral and geothermal energy exploration. It also is a unique tool in certain fields of basic scientific research, such as the exploration of both the continental crust (German KTB program, French GPF program), and the oceans (international ODP program) as well as studies carried out in the context of the deep disposal of radioactive waste.
Numerous highly-advanced tools have been developed in order to enable the physical and chemical characterization of the rocks intersected by the drill holes.