The Coral Islands and Associated Features of the Great Barrier Reefs: Discussion

The Great Barrier Reef Expedition of 1928-29 and the Royal Society and Universities of Queensland Expedition of 1973 are separated in time by only 44 years. In that period coral reef studies expanded greatly and the geomorphology of reefs and reef areas became a major theme of research. Up to 1928 it is almost true to say that no work had been done on coral islands, and the writings on reefs were almost entirely biological. W. M. Davis’s The Coral Reef Problem appeared in 1928. It was the first book that examined coral reefs from a geomorphological point of view. Davis made extensive use of deductive reasoning, but he did not examine, on the ground, the structure and formation of coral islands, although he travelled widely in coral regions and made great use of charts. He did, however, emphasize and discuss at length the importance of studying reefs in relation to the coast of the land they border. Thus he enlarged on the point, first made by Dana, that drowned valleys imply not only subsidence of the land they traverse but also of the foundation of the reefs in front of that land. This was a major contribution. Two other comments made by Davis are only of subsidiary importance - the unconformable contacts of reefs on the rocks on which they rest, and the disposal of detritus in lagoons, especially in subsiding areas. Davis’s conclusion was that Darwin’s theory of subsidence was the most convincing explanation of the way in which barrier reefs and atolls are formed. He also, rightly, acknowledged the force of Daly’s glacial control theory, but fluctuations of sea level in the Quaternary were regarded as relatively minor incidents in comparison with the much greater subsidence that was necessary to explain deep drowned valleys and the evidence of the Funafuti bore. Incidentally this bore and the much shallower one on Michaelmas Reef were the only ones that were made before 1928. Davis also demonstrated the significance of cliffing in the marginal belts and the general absence of cliffs within reefs in the truly coral seas. In short, up to about 1928 discussions on the origin of coral reefs were wholly theoretical; despite the swing towards Darwin’s hypothesis there were still supporters of the theories propounded by Murray, Agassiz, Gardiner and others.

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Victorian Coral Islands of Empire, Mission, and the Boys' Adventure Novel by Michelle Elleray

Victorian Periodicals Review ◽

10.1353/vpr.2021.0010 ◽

2021 ◽

Vol 54 (1) ◽

pp. 160-162

Author(s):

Jennifer Fuller

Keyword(s):

Coral Islands

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DNA barcoding the flowering plants from the tropical coral islands of Xisha (China)

Ecology and Evolution ◽

10.1002/ece3.4545 ◽

2018 ◽

Vol 8 (21) ◽

pp. 10587-10593 ◽

Cited By ~ 1

Author(s):

Shengchun Li ◽

Xin Qian ◽

Zexin Zheng ◽

Miaomiao Shi ◽

Xiaoyu Chang ◽

...

Keyword(s):

Dna Barcoding ◽

Flowering Plants ◽

Tropical Coral ◽

Coral Islands

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Characterizing carbonate facies using high-definition frequency decomposition: Case study from North West Australia

Interpretation ◽

10.1190/int-2016-0173.1 ◽

2017 ◽

Vol 5 (3) ◽

pp. SJ49-SJ59

Author(s):

Mohammed Al-Maghlouth ◽

Peter Szafian ◽

Rebecca Bell

Keyword(s):

Matching Pursuit ◽

Carbonate Facies ◽

High Definition ◽

Coherent Noise ◽

Sedimentary Processes ◽

North West ◽

Frequency Decomposition ◽

Facies Classification ◽

Barrier Reefs ◽

Northern Carnarvon Basin

Carbonate facies identification is difficult using conventional seismic attributes due to subtle lithologic changes that cannot be easily recognized. Therefore, there is a need to develop new methodologies to study their evolution and their associated sedimentary processes, which will eventually lead to better prediction for reservoir-quality rocks. New insights into the Cenozoic carbonates in North West Australia have been captured with the application of a high-definition seismic attribute workflow. The workflow starts with conditioning of the seismic volume using structurally oriented noise attenuation filters to remove any random and coherent noise from the input data. It also benefits from a high-definition frequency decomposition that matches the original seismic resolution without smearing interfaces using a “matching pursuit” algorithm. A color blend of multigeometric attributes, such as semblance and conformance, has also been used in the workflow to define edges and discontinuities present in the data within carbonate deposits that are attributed to depositional geometries, such as barrier reefs. Our workflow has been developed to investigate the geomorphology and the sedimentary processes affecting Cenozoic successions in the Northern Carnarvon Basin in North West Australia. Geomorphological and sedimentological observations have been documented such as an Eocene rounded carbonate ramp with evidence of slump blocks and scarps, Middle Miocene accretions generated due to longshore drift, and the presence of Pliocene-Pleistocene patch and barrier reefs. These observations were extracted as geobodies to allow for visualization, and they can be used in an automated seismically based facies classification scheme. The new appreciations are not only useful for understanding the carbonate evolution but can also be used to identify geohazards such as slumps ahead of future drilling.

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Forty-five years of change on low wooded islands, Great Barrier Reef

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1978.0053 ◽

1978 ◽

Vol 284 (999) ◽

pp. 63-80 ◽

Cited By ~ 18

Keyword(s):

Great Barrier Reef ◽

Coral Growth ◽

Barrier Reef ◽

Evolutionary Sequence ◽

The Holocene ◽

Additional Information ◽

Aerial Reconnaissance ◽

History Of ◽

Barrier Reefs

During the 1928-29 Expedition, centred at Low Isles, Spender mapped the ‘low wooded islands’ or ‘island-reefs’ of Low Isles and Three Isles in detail, and additional information was published by Steers, T. A. Stephenson and others. From this work, two different models of the evolution of low wooded islands were proposed, Spender holding that the islands were in a state of equilibrium resulting from their location on the reef, Steers that they could be placed in an evolutionary sequence. Moorhouse described the results of cyclones at Low Isles in 1931 and 1934, and Fairbridge & Teichert reconsidered the general issues following aerial reconnaissance and a brief visit to Low Isles in 1945. Subsequently, aspects of change since 1928-29 have been studied at Low Isles by W. Stephenson, Endean & Bennett in 1954 and by W. Macnae in 1965. Maps produced since 1929, however, have all been based on Spender’s surveys. In 1973, Low Isles and Three Isles were remapped in detail, and a direct comparison can now be made over an interval of 45 years. This shows changes in island topography, and substantial alteration in the size and location of shingle ramparts which has affected conditions for coral growth on reef flats. Mangroves have extended greatly at Low Isles, but not at all at Three Isles. The implications of these findings for the general models of Steers and Spender will be discussed and related to the Holocene history of the Great Barrier Reefs.

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Vulnerability of the Lakshadweep Coral Islands in India and Strategies for Mitigating Climate Change Impacts

Advances in Environmental Engineering and Green Technologies - Environmental Sustainability and Climate Change Adaptation Strategies ◽

10.4018/978-1-5225-1607-1.ch003 ◽

2017 ◽

pp. 64-96

Author(s):

B. K. Khanna

Keyword(s):

Climate Change ◽

Action Plan ◽

Climate Change Impacts ◽

Change Strategies ◽

Development Goals ◽

Change Impact ◽

Successes And Challenges ◽

Lakshadweep Archipelago ◽

Coral Islands

Strategies for mitigating climate change impact on the vulnerable Lakshadweep coral islands have been drawn up in accordance with the principles, guidelines and strategies laid down in the Indian National Action Plan on Climate Change (NAPCC). The region most vulnerable to inundation from accelerated sea level rise (at least 40 cm by 2100) is the Lakshadweep archipelago. The first section of the chapter reviews the origin and geophysical features, climate profile, sectoral impact of climate change and vulnerabilities of Lakshdweep. The second section deals with climate change strategies and their adaptation, recommending appropriate actions for coping strategies to be adopted by local communities to be resilient against the adverse impacts of climate change. The third section outlines the Lakshadweep Action Plan for Climate Change (LAPCC) and the fourth section describes integrating LAPCC within the NAPCC, successes and challenges ahead. For small islands it is a notable case study to emulate, mitigating the effects of climate change while not deviating from development goals.

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