Anomalously High Heat Flow Regions Beneath the Transantarctic Mountains and Wilkes Subglacial Basin in East Antarctica Inferred From Curie Depth

Abstract

The evolution of both the Transantarctic Mountains (TAMs) and Wilkes Subglacial Basin (WSB) (Figure 1) as well as their coupling are not fully resolved, despite their crucial role in potential future sea level rise (DeConto

The 3D crustal structure of the Wilkes Subglacial Basin, East Antarctica, based on joint inversion of gravity and magnetic data using variation of information

“…The resulting inversion mesh contains 244 cells east-west direction, 140 cells in north-south direction and 21 cells in the z direction (60 km below sea level). To constrain the model geometry, the bedrock topography from BedMachine version 3 [Morlighem et al, 2020], Curie point depths (CPD) [Lowe et al, 2023], and Moho depths [Pappa et al, 2019a] are used.…”

“…However, rocks lose their magnetic properties at the Curie temperature. Therefore, the Curie Depth Points from [Lowe et al, 2023] are introduced as an additional constraint. Joint VI inversion is carried out for all cells between the bedrock interface and the CPD interface.…”

“…CPD estimates are taken from [Lowe et al, 2023] and used as a bottom boundary condition for the susceptibility inversion. Below the CPD the crustal rocks have lost their magnetic properties and manuscript submitted to JGR Solid Earth of AGU journal therefore the joint inversion of magnetic and gravity data needs to be limited to crustal depth above the CPD.…”

“…Below the CPD the crustal rocks have lost their magnetic properties and manuscript submitted to JGR Solid Earth of AGU journal therefore the joint inversion of magnetic and gravity data needs to be limited to crustal depth above the CPD. The CPD estimates from [Lowe et al, 2023] have a 20 km resolution and are interpolated on a 7.5 km grid, matching the cell size of the inversion mesh, by applying statistical kriging using the python package PyKrig [Murphy et al, 2022]. After interpolation, the CPD map shows some values deeper than the Moho depths from Pappa et al (2019a) in the offshore area and along the coast.…”

“…Radiogenic heat production is predicted to contribute up to 40% to the surface geothermal heat flow [Artemieva and Mooney, 2001;Haeger et al, 2022;Hasterok and Chapman, 2011]. However, due to the lack of information on subglacial geology and crustal properties, incorporating accurate thermal crustal parameters such as radiogenic heat production and thermal conductivity is challenging and therefore current geophysical derived geothermal heat flow models commonly use global average values instead [Haeger et al, 2022;Lösing and Ebbing, 2021;Lowe et al, 2023;Martos et al, 2017;Shen et al, 2020;Stål et al, 2021]. For more in depth discussion of current Antarctic geothermal heat flow models the reader is referred to [Reading et al, 2022] and [Burton-Johnson et al, 2020].…”