It is always pleasing to see additional work undertaken on sedimentary successions that are critical to the understanding of Quaternary environmental changes. The deposits at Mary Ann Bay, as with other last interglacial (MIS 5e; 128-118 ka) coastal-marine successions in Tasmania, are critical for demonstrating that the region has experienced a different relative sea-level history to mainland southeastern Australia, and that parts of Tasmania have been uplifted by 16-17 m since the last interglacial maximum. Unfortunately, the recently published paper by Slee et al. (2012) gives credence to two thermoluminescence (TL) ages which must be inaccurate. In uncritically accepting the 30 ka TL ages, they encounter the dilemma that relative sea level at this time was 60 to 70 m below present sea level during the latter portion of the cool interstadial MIS3 (Chappell et al., 1996). To resolve their dilemma, they reinterpret the Mary Ann Bay succession as an aeolian facies. This note restates the widely published and unambiguous evidence for the shallow subtidal environment of deposition for the sedimentary succession at Mary Ann Bay and provides a brief commentary on the validity of the luminescence ages.
History
Citation
Murray-Wallace, C. V., Colhoun, E. A., Goede, A. & Quilty, P. G. (2012). Comments on Slee et al. (2012). A reassessment of Last Interglacial deposits at Mary Ann Bay, Tasmania. Quaternary Australasia 29: 4-11. Quaternary Australasia, 30 (1), 4-6.