Authors / CoAuthors
Glenn, K.C. | Chaproniere, G.C. | Opdyke, B.N.
Abstract
Positioned at the transition zone of the major hydrocarbon provinces of Browse and Bonaparte Basins, Ashmore Reef is built on what is thought to be Pleistocene antecedent topography. This mature, ovoid, shelf-edge reef experiences the seasonal oceanic influences of Indian Ocean and of the Indonesian-Through-Flow. The model for its development is derived from the post glacial (past 11,000 years) relative sea level curve, C14 dated facies changes and the reef growth phases extrapolated from the One Tree Reef model (Marshall & Davis 1982). A thorough visual examination of the reef was augmented with a series of 12 vibro-cores through algal-foraminiferal sand and coral, across the bioturbated platform. Changes in the lagoonal sediment facies were carbon dated giving dates ranging from 970 to 2020 (~70 years) BP. They indicated a major bio-facies change from robust vertical coral columns to an algal dominated reef crest and reef flats as sea level stabilised at ~2000 BP. Ashhmore Reef is presently characterised by high biodiversity and extensive coral growth, broad reef flats littered with coral boulders, and three vegetated cays. An extensive series of highly mobile and heavily bioturbated biogenic sand sheets adjoin two lagoons. Both are within a pronounced ovoid, algal-cemented, reef rim. The sediments comprised principally of Halimeda sp., coral fragments, foraminifera, molluscs and a range of coralline algae that infill the lagoon at up to 0.73 cm/yr. The three vegetated cays are capped with guano and all have wash-over deposits of pumice, wood, shell and coral.
Product Type
nonGeographicDataset
eCat Id
37510
Contact for the resource
Owner
Custodian
Cnr Jerrabomberra Ave and Hindmarsh Dr GPO Box 378
Canberra
ACT
2601
Australia
Point of contact
- Contact instructions
- PSCD
Keywords
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- External Publication
- ( Theme )
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- palaeontology
- ( Theme )
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- morphology
- ( Theme )
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- sequence stratigraphy
- ( Theme )
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- marine
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- AU-NTAU-WA
- Australian and New Zealand Standard Research Classification (ANZSRC)
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- Earth Sciences
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- Published_External
Publication Date
2001-01-01T00:00:00
Creation Date
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Purpose
Maintenance Information
unknown
Topic Category
geoscientificInformation
Series Information
Lineage
Unknown
Parent Information
Extents
[-13.0, -12.0, 123.0, 124.0]
Reference System
Spatial Resolution
Service Information
Associations
Source Information
Source data not available.