The petrogenesis of Mesozoic Gondwana low-Ti flood basalts

Abstract

New major, trace element and isotopic data for Jurassic basalts from SE Australia indicate that they are strikingly similar to the Jurassic tholeiitic rocks of Tasmania and the Transantarctic Mountains. These rocks are all characterised by low TiO2, P2O5, Na2O, Fe2O3, Ti Zr, Ti Y and ε{lunate}Nd, and high SiO2, Rb Ba, Rb Sr, 87Sr 86Sr and 207Pb 204Pb, relative to oceanic basalts. They therefore comprise a major province, termed the Ferrar magmatic province, which extended for 3000-4000 km across the Gondwana supercontinent. A review of the other Mesozoic low-Ti CFB's suggests that the Ferrar rocks are an extreme example of these magma types. It is striking that both the major and trace ele..