PROGRESSIVE DEFORMATION OF CRAVEN FAULT BELT IN THE PENNINES, ENGLAND

Abstract

Hercynian compression has folded and fractured the car- boniferous rocks in the pennines (England). The Hercynian deformation occurred during stephanian times in two pulses. The first pulse was in an approximately E-W direction, and the second pulse was produced by the activation of the North Craven Fault, with major dextral transcrurrent movements. A dextral shear zone thus developed in the Craven lowlands, resulting in the rotation of the compression direction from E-W to NNW-SSE. The second pulse gave rise to NNW and ENE joint sets, which are "AC" and "BC". The change in strike orientation of the joints near the North Cravern Fault results from a change in stress ori- entation. A higher density of stress trajectories is observed around the North Craven Fault which suggests a higher stress magnitude in this area. A weakened thus zone developed, which eventually gave rise to Craven fault belt.