FN Archimer Export Format PT J TI Atypical responses of a large catchment river to the Holocene sea-level highstand: The Murray River, Australia BT AF Helfensdorfer, Anna M. Power, Hannah E. Hubble, Thomas C. T. AS 1:1,2;2:2;3:1; FF 1:;2:;3:; C1 School of Geosciences, The University of Sydney, Sydney, NSW, 2006, Australia School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, 2308, Australia C2 UNIV SYDNEY, AUSTRALIA UNIV NEWCASTLE, AUSTRALIA IN DOAJ IF 4.379 TC 13 UR https://archimer.ifremer.fr/doc/00628/74035/73365.pdf https://archimer.ifremer.fr/doc/00628/74035/73366.pdf LA English DT Article CR MD 131 / AUSCAN BO Marion Dufresne AB Three-dimensional numerical modelling of the marine and fluvial dynamics of the lower Murray River demonstrate that the mid-Holocene sea-level highstand generated an extensive central basin environment extending at least 140 kilometres upstream from the river mouth and occupying the entire one to three kilometre width of the Murray Gorge. This unusually extensive, extremely low-gradient backwater environment generated by the two metre sea-level highstand captured most, if not all, of the fine-grained sediment discharged from the 1.06 million square kilometre Murray-Darling catchment. This material was sequestered within a >60 kilometre long, >10 metre thick valley-wide deposit of finely laminated mud. This previously unrecognised sediment trap persisted from 8,518 to 5,067 cal yr BP preventing sediment delivery to the marine environment. Its identification requires that mid-Holocene climate reconstructions for southeastern Australia based on fluctuations in the delivery of fine-grained sediment to the ocean offshore the lower Murray River’s mouth must be re-evaluated. PY 2020 PD MAY SO Scientific Reports SN 2045-2322 PU Springer Science and Business Media LLC VL 10 IS 1 UT 000532437000005 DI 10.1038/s41598-020-61800-x ID 74035 ER EF