Using speleothems to constrain late Cenozoic uplift rates in karst terranes
journal contribution
posted on 2022-06-10, 03:27authored byJohn Engel, J Woodhead, J Hellstrom, Susan WhiteSusan White, N White, H Green
The utility of speleothems as environmental and geological archives has greatly expanded with recent advances in geochronology. Here we reevaluate their ability to constrain late Cenozoic uplift in karst terranes. Using combined U-Th and U-Pb speleothem chronologies for the Buchan karst along the passive margin of southeastern Australia, we calculate a maximum uplift rate of 76 ± 7 m m.y.-1 maintained over the past 3.5 m.y. The timing and extent of this process is consistent with independent constraints on Neogene uplift in Australia, possibly in response to increased plate-boundary strain with New Zealand. Speleothem chronologies provide highly precise age control on individual events and the potential for near-continuous records across long periods of geological time, complementing and expanding upon existing uplift proxies.
Funding
Samples were collected from the Buchan caves under Victoria Department of Environment, Land, Water and Planning permit number 10008182, and we are grateful for the assistance of Parks Victoria Rangers throughout the project. We thank John Webb for valuable insights in the field; Mark Quigley, Malcolm Wallace, and Mike Sandiford for insightful discussions; and Fred Richards and two anonymous reviewers for comments that refined the manuscript. This research was facilitated by Australian Research Council grant FL160100028 to Woodhead.