Abstract


GEOMORPHOLOGY AND HOLOCENE EVOLUTION OF KIMBERLEY CORAL REEFS

The Kimberley Bioregion (North West Australia) is characterised by the largest macrotides of any tropical region in the world (about 11 m), frequent tropical cyclones and high-turbidity. Despite these challenging environmental conditions, the region is also known for extensive and diverse intertidal coral reef habitats. While the area has been recognised as an international biodiversity hotspot, it is still poorly investigated, compared to other reefal ecosystems in Australia, primarily due to its extreme remoteness and lack of infrastructure. A combination of remote sensing, sub-bottom profiling and associated sedimentological work produced a reef geodatabase, providing the first detailed geospatial study of coral reefs within the bioregion. More than 800 reefs have been documented and a geomorphic classification scheme for the Kimberley reefs was developed and includes a new “high intertidal” geomorphic class of reef. Reef coring shows that reef growth began soon after the post-glacial flooding of the antecedent substrate. High-resolution acoustic data, acquired along selected reefs, showed that pre-existing substrate has influenced the successive reef morphology. Global sea-level changes, controlled by ice age fluctuation events, provided a signal which is recorded in successive stages of the reef growth, separated by hiatuses. Two acoustic reflectors can be distinguished, marking the boundaries between Holocene (Marine Isotope Stage 1, last 12,000, 10-20 m thick) and Last Interglacial (MIS5, 125,000 ago, 12 m thick) reefs and an ancient Neoproterozoic rock foundation.

Authors

Bufarale, G., Curtin University, Australia, giada.bufarale@postgrad.curtin.edu.au

O'Leary, M. J., Curtin University, Australia, mick.oleary@curtin.edu.au

Collins, L. B., Curtin University, Australia

Stevens, A. M., Curtin University, Australia, M.A.Stevens@curtin.edu.au

Kordi, M. N., Curtin University, Australia, m.kordi@postgrad.curtin.edu.au

Solihuddin, T., Curtin University, Australia, tubagus.solihuddin@student.curtin.edu.au

Details

Oral presentation

Session #:34
Date: 06/23/2016
Time: 14:45
Location: 311

Presentation is given by student: Yes