The Hayfield Sandstone Play: the characterisation of a Mesoproterozoic sourced, Proterozoic sandstone reservoired, tight oil and gas play in the Beetaloo Sub-basin

Abstract

The Hayfield Sandstone is a Neoproterozoic, 10–15 m thick, very fine- to fine-grained sandstone, interpreted to have been deposited in a shelfal-marine environment. The reservoir sandstone is characterised by high porosity and low matrix permeability, which is complimented by partially mineralised open fractures which may contribute significantly to overall system permeability. Hydrocarbon phase across the identified play fairway is interpreted to range from a gas with the potential for condensate and liquefied petroleum gas streams to a light, ~38 API gravity oil. The extent of the prospective play fairway and the distribution and connectivity of reservoir facies is poorly constrained due to a limited number of well penetrations and poor resolution 2D seismic data. From the wells drilled to date, the gross area of the prospective play fairway could be as low as 300 km2 or greater than 1500 km2.