PESA SA/NT August Luncheon

Applications of radiometric dating for energy resources and carbonate mineralisation

Darwinaji Subarkah

(School of Physics, Chemistry and Earth Sciences, University of Adelaide)

Darwinaji Subarkah^{1, 3}, Angus L. Nixon¹, Sarah E. Gilbert², Alan S. Collins^{1, 3}, Morgan L. Blades¹, Alexander Simpson⁴, Jarred C. Lloyd¹, Georgina M. Virgo¹, and Juraj Farkaš ^{1, 3}

¹School of Physics, Chemistry, and Earth Science, Adelaide University, Adelaide, SA 5005, Australia.

²Adelaide Microscopy, Adelaide, SA 5005, Australia.

³MinEx CRC, Australian Resources Research Centre, Perth, WA 6151, Australia.

⁴British Geological Survey, Nottingham, NG12 5GG, United Kingdom

Abstract

Timing hydrocarbon maturation and carbonate mineralisation in sedimentary basins is often hindered by the scarcity of suitable dateable minerals. In order to address these challenges, we developed two novel in-situ laser-based methods that have the potential to quickly and accurately resolve these processes. The first method provides a tool to date clay phases in shales using Rb–Sr geochronology. We show that the Rb–Sr isotopic system in shales is sensitive to temperatures equivalent to the oil-gas window. The second technique demonstrates an approach for dating carbonate formation using U–Pb geochronology via a laser isotopic mapping approach. The laser rasters can be compiled into interactive maps, and this spatial and geochemical information can be used target multiple generations of carbonate mineralisation. Records of natural carbonate precipitation can be used as an analogue for assessing the potential of host rocks for carbon capture and storage.

Event Details:

Thursday 28th August 2025

Luncheon: 12 pm for a 12:30 pm start

Place: Ayer’s House, 288 North Tce, Adelaide

The luncheon will consist of 2 courses and drinks

Bookings close 5 pm Monday, 25th August 2025

Any late bookings will incur an additional $20 fee. Strictly no walk-ins.