Journal ArticleDOI
Shelf-wide erosion, deposition, and suspended sediment tranport during Cyclone Winifred, central Great Barrier Reef, Australia
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In this paper, the authors collected shelf sediments collected immediately before and after Cyclone Winifred crossed the central Great Barrier Reef shelf (1 February 1986) confirmed that the storm produced a normally graded, mixed terrigenous-carbonate storm layer extending 30 km offshore in water up to 43 m deep.Abstract:
Observation of shelf sediments collected immediately before and after Cyclone Winifred crossed the central Great Barrier Reef shelf (1 February 1986) confirmed that the storm produced a normally graded, mixed terrigenous-carbonate storm layer extending 30 km offshore in water up to 43 m deep. Distinct post-Winifred changes in the cross-shelf distribution of organic carbon and carbonate in the mud-fraction of the sediment suggest that suspended sediment transport was extensive and that the storm layer had multiple sediment sources. On a shelf-wide scale, the storm layer is composed almost entirely of reworked shelf sediment. Erosion depths were greater on the mid-shelf (20-40 m water depth) than on the inner shelf( 6.9 cm and 5.1 cm, respectively. Particles finer than medium sand were eroded and transported out of the mid-shelf. The inner-shelf portion of the storm layer formed by the combination of three sediment sources, including 1) seaward transport of terrigenous sediment in buoyant freshwater flood plumes, 2) resuspension and settling of inner-shelf sediment, and 3) resuspension and shoreward transport of mid-shelf sediment. Mass-balance calculations predict that at least 10-30% of the inner-shelf storm layer is composed of mid-shelf mud. Combined wave and wind-forced currents probably resuspended mid-shelf material and drove the suspended fraction alongshelf and shoreward a minimum distance of 15 km. The results suggest that tropical cyclones are capable of sporadic but efficient cross-shelf transport of suspended sediment. On shallow cyclone-prone shelves, suspended sediment may easily be exchanged between adjacent sedimentary facies. In ancient shelf sequences, the transport history of the mud will be complex, and stratigraphically equivalent facies may have similar mud types but completely different sands.read more
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Journal ArticleDOI
Transport of particles across continental shelves
TL;DR: In this paper, passive particles and their transport across (not necessarily off) continental shelves during high stands of sea level are investigated. But the authors focus on the portion of the water column closest to the seabed, where physical processes are effective where and when they influence the bottom boundary layer.
Book
The Geomorphology of the Great Barrier Reef: Development, Diversity and Change
TL;DR: This paper reviewed the history of geomorphological studies of the Great Barrier Reef and assessed the influences of sea-level change and oceanographic processes on the development of reefs over the last 10,000 years.
Journal ArticleDOI
High-resolution isotopic records from corals using ocean temperature and mass-spawning chronometers
TL;DR: A 6-year-long (1978-1984) δ 18 O and δ 13 C record from a Great Barrier Reef (Pandora Reef) Porites lutea coral based on near-weekly sample intervals is presented in this paper.
Journal ArticleDOI
Sea-level and environmental changes since the last interglacial in the Gulf of Carpentaria, Australia: an overview
Allan R. Chivas,Adriana García,Sander van der Kaars,Martine J.J. Couapel,Sabine Holt,Jessica M Reeves,David J Wheeler,Adam D. Switzer,Colin V. Murray-Wallace,Debabrata Banerjee,Debabrata Banerjee,David M. Price,Sue X Wang,Grant Pearson,N Terry Edgar,Luc Beaufort,Patrick De Deckker,Ewan Lawson,C. Blaine Cecil +18 more
TL;DR: In this article, a preliminary interpretation of the palaeoenvironments recorded in six sediment cores collected by the IMAGES program in the Gulf of Carpentaria is presented, which includes a record of sea-level/lake-level changes, with particular complexity between 80 and 40 years.