Macro- to Micro- scale structures in the Assynt Region of the Moine Thrust Belt

MACRO- TO MICRO- SCALE STRUCTURES IN THE ASSYNT REGION OF THE MOINE THRUST BELT

by Dr. Geoffrey E. Lloyd

SITE MAP 1. Looking N from Coire a' Bhaic (Site Map 2) across Loch Glencoul, Assynt, showing the general geological disposition. A Cambro-Ordovician sedimentary sequence of quartzites (CQ) and sandstones - shales, calc-gritstones and limestones (CO) rests unconformably (u/c) on Archaean Lewisian Gneisses (LG) and is overthrust to the WNW by rocks of the Moine Thrust Zone (ST, Sole Thrust; I, imbricates of CO rocks; GT, Glencoul Thrust of Lewisian Gneisses). The Moine Thrust carrying Precambrian Moine Schists over Cambrian Quartz mylonites outcrops to the right of the map on the Stac of Glencoul. Select a label-link for more details.

Assynt from Quinag

SITE MAP 2. Looking E from Quinag (Spidean Goinnich) across Loch Assynt and Inchnadamph towards the Moine Thrust Zone, showing the general geological disposition. A Cambro-Ordovician sedimentary sequence of Basal (BQ) and Pipe Rock Quartzites (PQ) and sandstones - shales, calc-gritstones and limestones (UC) rests unconformably (u/c) on Precambrian Torridonian sandstone (T), which in turn is unconformable on Archaean Lewisian Gneisses (LG). The Cambro-Ordovician rocks have been overthrust to the WNW by rocks of the Moine Thrust Zone (ST, Sole Thrust; I, imbricates of CO rocks; GT, Glencoul Thrust of mylonitised Lewisian Gneisses and quartzites). The Moine Thrust carrying Precambrian Moine Schists over Cambrian Quartz mylonites outcrops in the far distance (not seen). Select a label-link for more details - especially SBF, the Skiag Bridge back thrust fault, to see the development of cataclastic fault rocks.