This map presents radiogenic crustal heat production values calculated from available geochemical data from basement rock exposures from across the Australian Antarctic Territory (AAT). Heat production is derived from the radiogenic decay of the radioactive elements, primarily, U, Th and K. This map, along with the companion GA record (2012/63), highlights the magnitude and heterogeneity of crustal heat production across the AAT, and provides earth scientists with the first crustal heat production assessment across much of East Antarctica.
Crustal heat production values across the AAT show a wide range from negligible to as much as 65 'Wm-3. Generally, elevated heat production values are characteristic of Cambrian felsic intrusives, with intermediate values from Proterozoic intrusive and metasediments (2-8 Wm-3), and low values (<2 'Wm-3) from Archean rocks.
A good illustration of the correlation of geological age with heat production is from Prydz Bay (map 5), where the Vestfold Hills (mostly ~2500 Ma in age) exhibits uniformly low heat production (average ~0.8 'Wm-3), whereas Proterozoic rocks south of the Vestfold Hills have intermediate values (average ~2.6 'Wm-3). Cambrian intrusives, in contrast, have significantly elevated values (average ~15 'Wm-3).
We anticipate that this simple compilation of crustal heat production may form a basis for future studies on the thermal structure of the East Antarctic crust, in particular, sub-glacial heat flow, which remains a critical, yet poorly characterised, boundary parameter controlling the dynamic behaviour of the vast Antarctic ice sheet.
For further information and data tables, the reader is referred to 'A reconnaissance crustal heat production assessment of the Australian Antarctic Territory (AAT)' by C. J. Carson and M. Pittard, GA record 2012/063 (pp 57), Geocat 74073.
