Quantifying exhumation using compaction and vitrinite reflectance in the Southern Bonaparte Basin, North West Shelf, Australia

The Magnitude of Exhumation in the Kidson Sub-Basin, Western Australia, Usingthermal and Compaction Techniques

“…In this study, the thermal and compaction techniques were both employed to estimate the magnitude of exhumation in the Kidson Sub-basin. Combining these two methods offers the advantage of providing independent results that can be used to constrain exhumation magnitudes in basins (Johnson et al, 2017;Makuluni et al, 2021). The methods are described in detail in the following sections.…”

“…As a method, it is generally accepted as one of the most accurate methods for estimating exhumation using paleo thermal indicators and resolves some of the pitfalls of semi-log plots and empirical depth conversions (Corcoran and Doré, 2005). The technique has been used to quantify exhumation in several basins including the Brooks Range, Alaska (O'sullivan et al, 1995), Northern Australia basins (Duddy et al, 2003), Sichuan Basin, China (Zhu et al, 2019) and Bonaparte Basin, North West Shelf, Australia (Makuluni et al, 2021). The general procedure involved in using this method to estimate the magnitude of exhumation has been described below.…”

“…These diagenetic processes are considered to be minimal for clastic sediments with burial depth ranging from 2 to 3 km (80 0 C isotherm) (Corcoran and Doré, 2005). Also, Makuluni et al (2021) argued that diagenetic effects including porosity enhancement through dissolution and porosity reduction through cementation generally counteracts and cancel out, leaving mechanical compaction as the main mechanism driving porosity reduction. Thus, the porosity of a sedimentary unit reflects the overall mechanical and thermochemical state of the unit and is a reflection of its maximum depth of burial (Tassone et al, 2014).…”

“…By establishing a reference porosity-depth curve (which describes the normal compaction within the basin) and comparing that curve with the present-day porosity (obtained from core or well log), the difference in depth axis represents the potential exhumation that occurred between the time of maximum burial and the present-day at the well location (Corcoran and Doré, 2005;Hillis, 1995;Johnson et al, 2017;Licciardi et al, 2020). The approach has been used to quantify the amount of exhumation in several basins across the world including the Otway Basin, Australia (Tassone et al, 2014), Southern North Sea basins, UK (Corcoran and Doré, 2005;Hillis, 1995), Barents Sea, Norway (Licciardi et al, 2020), Broom Platform, Canning Basin, Australia (Johnson et al, 2017) and Bonaparte Basin, North West Shelf, Australia (Makuluni et al, 2021). We focused our study on normally pressured clastic sedimentary units and looked out for signs of extreme cementation that may potentially serve as sources of errors.…”

“…6a). For the sandstone compaction technique, we followed the approach presented in Corcoran and Doré (2005) and (Makuluni et al, 2021). Thus, the reference curve was constructed following Athy's (1930) porosity-depth trend (Eq.…”