LATE PROTEROZOIC RIFT FAULTS AND BASEMENT-COVER RELATIONSHIPS WITHIN THE BEN-MORE THRUST SHEET, NW SCOTLAND

Recently proposed models for the tectonic evolution of Northern Scotla nd, involving lithospheric extension during the late Precambrian, are supported by new discoveries and interpretations of early normal fault s within the Moine Thrust Belt, Such structures control the preservati on of Torridonian sediments beneath the sub-Cambrian unconformity, The Ben More thrust ramp from basement into the Cambrian cover may have b een controlled by the early faults. Major synclines within the Ben Mor e thrust sheet appear as tightened half-grabens and thus are composite structures, This may require a re-examination of the field relationsh ips between these folds and the apparently syn-tectonic alkaline intru sions that have been used to date thrust activity.