Une mesure de la perméabilité et du fluage d'une caverne dans le sel

Abstract Rock mass properties differ significantly from those measured on samples in the laboratory. A test has been performed on a deep brine-filled cavern, with the objective of measuring the equilibrium pressure reached when the cavern was closed. Such an equilibrium is reached when salt mass creep, which leads to cavern shrinkage, balances brine permeation through the cavern wall. A K = 2·10 −19 m 2 value of the average in situ intrinsic permeability has been deduced from the test; it is significantly higher than the intrinsic permeability measured in a well or in the laboratory. This result supports cavern abandonment scenarios in which the risk of natural fracturation due to high brine pressures is alleviated.