Fault Reactivation in the Vicinity of Landslides in South Wales, UK

During mining subsidence geological faults may undergo reactivation, resulting in the appearance of fault scarps on the ground surface. In the South Wales Coalfield numerous fault scarps and ground fissures occur on the moorland plateaux. These features differ markedly from other cases of mining-induced fault reactivation that have been documented throughout the coalfields of the UK, due to their magnitude and extent. Many large landslides have developed in association with these features and it appears that they may play an important role in the initiation of first-time slope movements and the reactivation of existing landslides. Mining has been practiced in the South Wales valleys over a period of at least 150 years and available evidence suggests that it is the effects of mining subsidence along pre-existing faults that has significantly contributed to their dramatic present-day development. However, the fault scarps probably represent several phases of reactivation and the possibility that these features, albeit in a subdued form, existed prior to mining cannot be ruled out, although this is difficult to prove.

• INTRODUCTION

• CHARACTERISTICS OF THE FAULT SCARPS

• CHARACTERISTICS OF THE GROUND FISSURES

• ASSOCIATION OF FAULTING AND LANDSLIDES

• LATERAL SPREADING OF THE MOORLAND PLATEAU

• CONCLUSIONS

• ACKNOWLEDGEMENTS

• REFERENCES