THE INTERPLAY BETWEEN FLUIDS, FOLDS AND THRUSTS DURING THE DEFORMATION OF A SEDIMENTARY SUCCESSION

In this paper, field evidence is presented to support the idea that fluid pressures in excess of lithostatic pressure were operating during the initiation and reactivation of large thrusts and folds in the Wenlock shales of Llangollen, North Wales. It is also argued that as major thrusts are reactivated and as major folds amplify into finite structures they in turn exert an influence on the subsequent migration and concentration of fluids within the deforming sedimentary succession.