Tertiary: The Emergence of Modern Reef Ecosystems
Published:January 01, 2002
Following the major mass extinctions at the Cretaceous-Tertiary boundary, reef ecosystems slowly recovered and scleractinian corals appeared progressively as the most efficient framework producers of Cenozoic times. This occurred, however, in several steps involving successively speciation and diversification of assemblages, acquisition of reef-building capacities, and expansion of reef ecosystems. Although buildups were represented mainly by reef mounds and mud mounds from Danian to early Eocene times, typical framework reefs dominated by coral assemblages became the most common type of bio construction from the middle Eocene, Buildups remained relatively scarce during the early Tertiary, however, and acquired a widespread development from the late Oligocene onwards, with an acme of reef expansion during the early to middle Miocene. Distribution, abundance, and biotic composition of buildups are driven by the interplay of many abiotic and biolic factors acting at various temporal and spatial scales. Interaction of climate and plate tectonics in controlling oceanic circulation and potential marine seaways permitting faunal exchanges and dispersion led to the splitting of the cosmopolitan Tethyan reef province of the Late Cretaceous-early Tertiary into the three major reef provinces of the Mediterranean, Caribbean, and Indo-Pacific during Miocene times. The latitudinal contraction of the tropical-subtropical belt by taking the Mediterranean region out of the reef belt finally left, at the end of the Miocene, the two main reef Provinces existing today, the Caribbean and the Indo-Pacific. The very gradual acquisition of modern reef characterisdcs during the Tertiary contrasts with rather sudden biota turnovers, in particulara t the Eocene-Oligocene and at the Oligocene-Miocene boundaries. The primary characteristics of Tertiary buildups as recorded in the PaleoReef database clearly appear to exert major control upon their reservoir potential.
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Phanerozoic Reef Patterns
Detecting patterns and processes of ecosystem evolution is among the main challenges of an integrated earth system science in the 21st century. The evolution of reefs reflects changes triggered by evolutionary innovations and variations in global and regional controls at different scales. The prime fossil record of Phanerozoic reefs offers the opportunity to trace these patterns through space and time. Phanerozoic Reef Patterns presents a comprehensive and up-to-date review on the history of reef building in the last 540 million years. A selection of internationally respected reef specialists presents a database on ancient reefs that is hardly available for any other ecosystem. The thoroughly documented patterns are analyzed with respect to global change, whose impact on living reefs is intensely discussed today. Phanerozoic Reef Patterns stands out from recent reviews on reef evolution by its careful qualitative and quantitative approach based on a comprehensive and multifaceted databank, by the strong focus on data, by a complete and unified coverage of the Phanerozoic from the Early Cambrian to the late Neogene, by emphasizing paleogeographic reef distributions presented on 32 newly developed color maps, and by a detailed index that makes the book a valuable research tool.