Preservation of coralline-algal reef frameworks. / Bosence, Daniel.

Proceedings of The Fifth International Coral Reef Congress. ed. / C Gabrie ; M Harmelin. Vol. 6 1985. p. 623-628.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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Abstract

An analysis of coralline-algal frameworks from a range of reefs from temperate latitudes to the tropics indicates that their preservational histories are primarily controlled by their hydrodynamic setting. The different preservational histories of high- and low-energy reefs are discussed under the following headings: 1) Construction. Reef frameworks are constructed from crustose or branching coralline algae. High-energy reef frameworks are constructed from densely superposed thick crusts and fused thickly branched thalli. Reef frameworks from sheltered environments are leafy, delicate, crustose frameworks or thin, unfused branching thalli. 2) Early cementation. Coralline frameworks may be cemented by micrite or fibrous aragonite cements and intraske1eta1 micrite. Cemented frameworks are found in high energy coralline algal ridges. Low energy frameworks only possess intraske1eta1 cements. 3) Bioerosion. Robust frameworks from well-cemented high-energy reefs are characterised by pervasive hard substrate micro- and macro-borers who may remove all of the framework. Occasional relics may be preserved in a nu1tigenerationa1 reef rock. Uncemented quiet water reefs with their thinner branches and crusts do not attract such bioerosion. However burrowing organisms break up the framework following weakening by microborers and little is preserved in life position. 4) Sedimentation. Sediments derived from high energy reefs are bimodal and comprise coarse particles derived fran wave breakage and fine particles fran borers. Fine particles are depoeited away from the reefs in quieter water settings. The more fragile frameworks from quiet water reefs are mainly broken by wave action and bioturbation deposited as wackestones and packstones around reef frameworks. 5) Dissolution. Solution cavities are not common in coralline algal reefs but some are described fran sub-tropical patch-reefs. Tertiary coralline-algal reef frameworks are compared and interpretations made in the light of this work fran present day reefs.
Original languageEnglish
Title of host publicationProceedings of The Fifth International Coral Reef Congress
EditorsC Gabrie , M Harmelin
Pages623-628
Number of pages6
Volume6
Publication statusPublished - 1985
This open access research output is licenced under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.

ID: 33460464