A rapid sediment pulse induced by glacial melting during the MIS 8/7e transition buried well-developed karst in the Railton Valley, Tasmania, Australia

No Thumbnail Available
Date
2021-08-16
Journal Title
Journal ISSN
Volume Title
Publisher
John Wiley & Sons, Inc
Abstract
Recent catastrophic sinkhole collapse caused by regional water table lowering induced by quarrying has led to the partial exhumation and reactivation of a buried karst cave system in the floor of the Railton Valley in the lowlands of northern Tasmania, Australia, and widespread sinkhole development. Extensive silty sediments exposed in sinkholes, OSL dated to approximately 237 ka, are interpreted to be lacustrine deposits derived from rapidly deposited glacial outwash. The silty sediments have mineralogy consistent with derivation from a source in the upper Mersey catchment rather than locally and are interpreted to be the product of rapid melting of the Mersey Valley glacier during the MIS 8/7e transition. Thick Last Glacial alluvial fan and Holocene flood-plain deposits mantle the lacustrine sediments. Exposures of glacial erratics and weathered till in streambeds provide further evidence that the valley was impacted by earlier Pleistocene glaciations. © 2021 The Boreas Collegium. Published by John Wiley & Sons Ltd
Description
Advance copy in Boreas.
Keywords
Sediments, Valleys, Water tables, Caves, Glaciers, Tasmania, Australia
Citation
Slee, A., McIntosh, P. D., Woodward, C., Wang, N., & Gadd, P. (2021). A rapid sediment pulse induced by glacial melting during the MIS 8/7e transition buried well‐developed karst in the Railton Valley, Tasmania, Australia. Boreas, 51(1), 185-200. doi:10.1111/bor.12538
Collections