Regional organic geochemistry of host sediments of Palaeoproterozoic McArthur River Ore deposit, Australia

The 1,640 Ma HYC (Here's Your Chance) deposit at McArthur River, Northern Territory, Australia, is one of the largest and least metamorphosed Proterozoic stratiform lead-zinc-silver deposits in the world. The thermal history of the deposit is a currently not well understood, both low and high temperature mechanisms have been proposed. From our study we were able to estimate (from both kerogen and bitumen thermal maturity indices which concur) the thermal maturity to be equivalent to Ro 1.1-2.0%, corresponding to the wet gas generation zone, with a maximum relatively low burial temperature range of 120-180 °C in the ore samples. Regionally, temperatures were not further constrained due to the complex and dynamic nature of the sedimentary environment.