Characterisation of a clay formation : Synthesis of the main results obtained from Tournemire tunnel
The objective of this study, carried out in the toarcian argilites from the tunnel of Tournemire, was to determine the confining capacity of clay formation and, in particular, to examine the fluid movements into the clay. In order to determine the circulation of groundwater into the clay, isotopic studies with natural isotopes 14C, 36Cl, 129I, 18O, 13C and U/Th ratio, were performed. Using 18O and 2H, water was extracted from the area by diffusion and although difficulties were encountered, it proved to be the most efficient method. The water existed as either a mixture of conate and meteoric water or as a diphasic system of the two. This led to the assumption that there has been no groundwater circulation for at least 20,000 years.
Bibliographic Reference: EUR 15756 FR (1994) 155 pp., FS, ECU 18.50
ISBN: ISBN 92-826-8353-2
Record Number: 199410793 / Last updated on: 1994-12-06
Original language: fr
Available languages: fr