oa Differential Fracturing Pattern in Clay/limestone Alternations and Fluid Circulations in the Maltese Islands

Draining faults propagating from carbonates to clay layers could significantly impact the safety of nuclear waste storages, as investigated in the Bure Underground Research Laboratory (URL, France). In this study, we show that the draining properties of such faults seem to depend mainly of the fault throw magnitude. The results obtained on the Maltese Islands indicate that large faults (throw >50m) as well as small faults (throw <5m) does not lead to fluid circulation. On the opposite, intermediate faults propagates in the clay formation and lead to significant fracturation and fluid flows, including associated mineralisations.