Traces of historical tropical cyclones and tsunamis in the Ashburton Delta (north‐west Australia)

• DOI: 10.1111/sed.12192
• Publication Date: 2015-01-27T14:30:36Z
• Authors: Simon Matthias May; Dominik Brill; Max Engel; Anja Scheffers; Anna Pint; Stephan Opitz; Volker Wennrich; Peter Squire; Dieter Kelletat; Helmut Brückner
• Keywords: Beach ridge; Chronostratigraphy

Abstract Although the north‐western coast of Western Australia is highly vulnerable to tropical cyclones and tsunamis, little known about geological imprint historic prehistoric extreme wave events in this particular area. Despite a number site‐specific difficulties such as post‐depositional changes preservation potential event deposits, both tsunamis may be inferred from geomorphology stratigraphy beach ridge sequences, washover fans coastal lagoons or marshes. A further challenge differentiation between tsunami storm deposits record, particularly where modern and/or historical reports on are not available. This study presents high‐resolution sedimentary record Ashburton River delta (Western Australia) spanning approximately last 150 years. detailed characterization provided, robust chronostratigraphy for investigated sequence established based multi‐proxy sediment analyses optically stimulated luminescence dating. Combining sedimentological, geochemical data, layers assigned cyclone separated deposits. For first time, 1883 Krakatoa 1977 Sumba records part Australia. It demonstrated that applied archives with favourable characteristics can provide accurate chronostratigraphies even decadal timescale. The results contribute data pool Holocene stratigraphies; however, they also demonstrate how short‐lived dynamic environments.