The Palmerville fault system: A major imbricate thrust system in the Northern Tasmanides, North Queensland

Abstract

Along part of the Precambrian‐Palaeozoic boundary in northern Queensland adjacent Palaeozoic flysch sequences (1) are separated by major reverse faults, (2) differ markedly in sedimentary characteristics and (3) have anomalous stratigraphic relations suggesting that they were originally deposited far apart. Internally, the sequences young mainly to the west towards the basement. These relationships suggest a tectonic model in which the Palmerville Fault is the principal fault in a complex imbricate thrust system that has resulted in the basement rocks over‐riding sediments of the Hodgkinson Province. The Palmerville Fault has been steepened by later movements on the underlying faults and by regional shortening. The fault is localized along a pre‐existing (?)Precambrian mylonite zone. A minimum age of Late Carboniferous (300 Ma) has been obtained for the last major fault movement by K‐Ar dating of granitoids intruding the fault.