The Minex CRC is the world's largest mineral exploration collaboration bringing together Industry, Government and Research Organisations. Within MinEx CRC, the National Drilling Initiative (NDI) is designed to undertake precompetitive geoscience research and drilling in underexplored, but potentially prospective regions. One of the first projects in the NDI is in the South Nicholson Region of the Northern Territory (NT) in collaboration with Geoscience Australia and the Northern Territory Geological Survey.
The South Nicholson Basin, and underlying Lawn Hill Platform region of the NT have the potential to host sediment hosted base metal mineral deposits, critical minerals as well as hydrocarbons. The region is poorly understood compared with the neighbouring resource rich areas of the McArthur Basin and the Mount Isa Province. Providing baseline data in frontier basins is essential as legacy data coverage can often be inadequate for making investment decisions, particularly with new commodities where exploration may not have the required information.
In 2017, Geoscience Australia acquired the L210 South Nicholson Deep Crustal Seismic Reflection Survey. This survey demonstrated the existence of an approximately 1550 km2 sedimentary depocentre underlying the surface sediments of the Georgina Basin, and coincident with a notable gravity low. This depocentre has been termed the ‘Carrara Sub basin’ and its successions may host a continuation of the resource-rich sediments located on the northern Lawn Hill Platform of northwest Queensland, in addition to South Nicholson stratigraphy that has never been penetrated by drill core.
MinEx CRC and its partners seek to better understand the geology and resource potential of the Carrara Sub basin through the drilling of the first deep vertical stratigraphic borehole in the region – known as the NDI Carrara-1 stratigraphic well. This borehole has been designed to answer key scientific questions suggested by Geoscience Australia and the Northern Territory Geological Survey including determining geological and geochemical characteristics of sedimentary units from fresh drill core, identifying any evidence of alteration or fluid flow, and finally determining whether there are favourable ingredients that can be used as indication of a mineral or petroleum system. Both physical samples (e.g. drill core and cuttings) and downhole data (e.g. wireline geophysical data) will be acquired over the entire borehole interval, to an approximate depth of 2000 m, to address these questions.
Drilling of NDI Carrara-1 is set to be completed by the end of 2020. This presentation will provide a rationale for drilling the NDI Carrara-1 stratigraphic drill core and will present preliminary data generated through drilling. The South Nicholson NDI has already provided and integrated new geoscience data and knowledge in the region, and NDI Carrara-1 will allow for direct testing of resource potential. This precompetitive data is fundamental to underpinning increased industry investment and sustainable economic development in this greenfields region of northern Australia.
Abstract presented at the 2021 Australian Earth Sciences Convention (AESC)
