A study of the Tasmanian dolerites with particular reference to the differentiation of the Red Hill dolerite-granophyre association

Abstract

The Tasmanian dolerites were intruded into essentially flat-lying Permian and Triassic sediments in the form of sheets, commonly exceeding 1000 feet in thickness, large dyke-like intrusions up to one mile in width, and transgressive bodies. The dolerite is post Triassic and pre-Tertiary in age, and Hills and Carey (194-9, 54-) and Banks (1958, 234-) suggest that the intrusions took place in the Jurassic. They crop out over more than 6,000 square miles, and Edwards (1942, 452) has estimated that the volume of magma intruded was of the order of 3,000 cubic miles. (First paragraph of Introduction).