eCite Digital Repository

Punctuated progradation of the Seven Mile Beach Holocene barrier system, southeastern Tasmania

Citation

Oliver, TSN and Donaldson, P and Sharples, C and Roach, M and Woodroffe, CD, Punctuated progradation of the Seven Mile Beach Holocene barrier system, southeastern Tasmania, Marine Geology, 386 pp. 76-87. ISSN 0025-3227 (2017) [Refereed Article]

Copyright Statement

Copyright 2017 Elsevier B.V.

DOI: doi:10.1016/j.margeo.2017.02.014

Abstract

Prograded barriers are depositional coastal landforms which preserve past shoreline locations and have been studied in order to understand the fundamental drivers of barrier formation. This paper reconstructs the Holocene history of the Seven Mile Beach, prograded barrier in Tasmania, Australia using optically stimulated luminescence (OSL) dating, ground penetrating radar (GPR), light detection and ranging (LiDAR) elevation models and sedimentological analyses. Shoreline progradation of the barrier commenced around 7300 years ago and continued to near present despite a ∼3000 pause in deposition between 6700 and 3600 years ago indicative of substantial changes in sediment availability. GPR imaged subsurface structures contain a record of seaward dipping reflectors preserved as sediment supplied beaches and dunes leading to shoreline progradation. In the past 500 years a large transgressive dune has formed, built from reworked barrier sands, and now dominates the eastern portion of the barrier implying that shoreline progradation has ceased. This study reaffirms the notion that relict foredune ridges are strongly aligned with modal wave refraction patterns in planform and emphasises the importance of sediment delivery as a key driver of shoreline progradation through beachface and dune accretion. The substantial pause in shoreline progradation on this barrier system, as observed on others around the world, requires further explanation. Although changes in sediment delivery have been inferred, it may also be appropriate to reopen the debate on Holocene sea-level change in Tasmania.

Item Details

Item Type:Refereed Article
Keywords:relict foredune ridges, transgressive dune, optically stimulated luminescence, ground penetrating radar, LiDAR topography, coast, geomorphology, change, Holocene
Research Division:Earth Sciences
Research Group:Physical Geography and Environmental Geoscience
Research Field:Physical Geography and Environmental Geoscience not elsewhere classified
Objective Division:Environment
Objective Group:Ecosystem Assessment and Management
Objective Field:Ecosystem Assessment and Management of Coastal and Estuarine Environments
Author:Sharples, C (Mr Chris Sharples)
Author:Roach, M (Dr Michael Roach)
ID Code:115260
Year Published:2017 (online first 2016)
Deposited By:Geography and Spatial Science
Deposited On:2017-03-13
Last Modified:2017-10-30
Downloads:1 View Download Statistics

Repository Staff Only: item control page