Evidence of a Late Pre-Cambrian Glaciation in the Kimberley Region of Western Australia

Abstract

Abstract Sediments of late Pre-Cambrian age mapped in the Kimberley Region of Western Australia have all the characteristics of tillite, and their glacial origin is confirmed by: the presence of very large polished and striated erratics, the great diversity of megaclasts, their regional extent, and the presence of striated, grooved, and polished quartzite bedrock directly beneath the tillite. Faceted and flat-iron-shaped pebbles are rare or absent; most megaclasts tend towards an ellipsoidal shape—an observation in agreement with recent theories of glacial abrasion.