Controls On Carbonate Platform And Reef Development

Carbonate platforms and reefs emerge, grow and die in response to intrinsic and extrinsic mechanisms forced primarily by tectonics, oceanography, climate, ecology and eustasy. These mechanisms, or controls, create the physical, biological and chemical signals accountable for the myriad of carbonate depositional responses that, together, form the complex depositional systems present in the modern and ancient settings. If we are to fully comprehend these systems, it is critical to ascertain which controls ultimately govern the "life cycle" of carbonate platforms and reefs and understand how these signals are recorded and preserved. Deciphering which signals produce a dominant sedimentological response from the plethora of physical and biological information generated from superimposed regional to global-scale controls is critical to achieving this goal. With this understanding, it may be possible to extract common time- and space-independent depositional responses to specific mechanisms that may, ultimately, be used in a productive sense. Extensive research on a wide variety of carbonate platform and reefal systems in the past few decades has provided the foundation and understanding necessary to take carbonate research to a new level. With assistance from rapidly advancing computer software and an increasing use of cross-disciplinary integration, carbonate research is shifting from description and morphological analysis towards a science that is more focused on the assessment of process and genetic relationships. The aim of this special publication is to present a cross section of recent research that shows this evolution from a variety of perspectives and scales using examples distributed throughout the Phanerozoic.

This volume covers many subjects relative to geology of carbonate platforms and adjoining slopes and basins. A preliminary section based on principles of deposition and computer modeling studies is followed by a group of a dozen papers devoted to examples of carbonate platforms on passive cratonal margins resuting from rifting.The volume also considers halos of carbonate developed as a fringe around the pericratonic Permian basin as well as some examples of isolated offshore platforms.

A strong case can be made that foreland basins are where the casual links between sedimentation and tectonic events were first recognized, as evidenced by the interpretations of geologists working in classic foreland areas. This Special Publication was derived from a Research Symposium entitled "Stratigraphic Sequences in Foreland Basins" held at the AAPG-SEPM joint annual meeting on June, 1992, in Calgary, Alberta, Canada. This volume provides a well-balanced perspective of current research on foreland basin stratigraphy and also serves as another element in the evolving framework that comprises our understanding of foreland basins. Given that so many of earth's resources are found in foreland basins and that foreland basin strata often provide the only preserved record of the tectonic events that led to basin development, the impetus for continued studies of foreland basin strata should remain for many generations of geologists to come.

This volume also discusses the computer modelling of carbonate cycles and sequence analysis. This will prove an invaluable text for senior undergraduate and postgraduate students in the earth sciences in general and will also be of value to the professional researcher. Carbonate platforms contains contributions from an international authorship and the volume has been edited by one of the most respected names in the earth sciences. Areas covered include; early rifting deposition; examples from carbonate sequences of Sardinia (Cambrian) and Tuscany (Triassic-Jurassic), Italy; geometry and evolution of platform-margin bioclastic shoals, late Dinantian (Mississippian), Derbyshire, UK; cyclic sedimentation in cabonate and mixed carbonate/clastic environments; four simulation programs for a desktop computer; middle Triassic carbonate ramp systems in the Catalan Basis, N.E. Spain; facies, cycles, depositional sequencies and controls; stages in the evolution of late Triassic and Jurassic platform carbonates; western margin of the Subalpine basin, Ardech, France. The formation and drowning of isolated carbonate platforms; tectonic and ecologic control of the Northern Apennines; controls on Upper Jurassic carbonate build up development in the Lusitanian Basin, Portugal; Hauterivian to Lower Aptian carbonate shelf sedimentation and sequence stratigraphy in the Jura and northern Subalpine chains (southeastern France and Swiss Jura); basement structural controls on Mesozoic carbonate facies in northeastern Mexico; the Aptian-Albian carbonate episode of the Basque-Cantabrian Basis (Northern Spain); general characteristics, controls and evolution; response of the Arabian carbonate platform margin slope to orogenic closing of an ocean basin, Cretaceous, Oman.

Preface -- Exposure, drowning and sequence boundaries on carbonate platforms -- The origin of the Great Barrier Reef: the impact of Leg 133 drilling -- Development and demise of mid-oceanic carbonate platforms, Wodejebato Guyot (NW Pacific)-- Stable tropics not so stable: climatically driven extinctions of reef-associated molluscan assemblages (Red Sea and western Indian Ocean; last interglaciation to present) -- Sedimentary cycles in carbonate platform facies: Fourier analysis of geophysical logs from ODP Sites 865 and 866 -- Aptian-Albian eustatic sea-levels -- Origin of white sucrosic dolomite within shallow-water limestones, ODP Hole 866A, Resolution Guyot, Mid-Pacific Mountains: strontium isotopic evidence for the role of sea water in dolomitization -- Computer simulation of a Cainozoic carbonate platform, Marion Plateau, north-east Australia -- Quaternary and Tertiary subtropical carbonate platform development on the continental margin of southern Queensland, Australia -- Pleistocene reef complex deposits in the Central Ryukyus, south-western Japan -- Morphology and sediments of the fore-slopes of Mayotte, Comoro Islands: direct observations from a submersible -- Tectonic and monsoonal controls on coral atolls in the South China Sea -- Steady-state interstitial circulations in an idealized atoll reef and tidal transients in a deep borehole by computer simulation -- Environmental and tectonic influence on growth and internal structure of a fringing reef at Tasmaloum (SW Espiritu Santo, New Hebrides island arc, SW Pacific) -- Lagoonal sedimentation and reef development on Heron Reef, southern Great Barrier Reef Province -- Terrigenous sediment accumulation as a regional control on the distribution of reef carbonates -- Comparison between subtropical and temperate carbonate elemental composition: examples from the Great Barrier Reef, Shark Bay, Tasmania (Australia) and the Persian Gulf (United Arab Emirates).

This book is the first comprehensive documentation and interpretation of modern neritic carbonate sediments on the southern Australian continental margin, the largest cool-water carbonate depositional system on the globe. The approach is classical but the information is new. A brief chapter of introduction is followed by a section that describes the setting of the continental margin in terms of the regional geology, its evolution through time, the climate, and the complex oceanography. The setting is further explored in chapter 3 that outlines the Pleistocene history of sedimentation in this region. This is particularly important since many of the surficial sediments have a partial older history. The following section on the carbonate factory describes in detail the nature of the animals and plants that determine the nature of the sediments and the environmental conditions that control their distribution. The shelf itself cannot be discussed in isolation and thus a short chapter on the marginal marine environment is presented. The core of the book comprises two chapters that document the suite of depositional facies and their composition and then the suite of depositional environments where these sediments are found. The variety of deposits in this vast area is such that three chapters are devoted to the character of the materials on the southwestern shelf the south Australian sea and the southeastern shelf. The diagenesis that affects these sediments is tackled in a chapter after all the attributes are documented because they are intimately linked to different controls. The book finishes with a summary chapter that also addresses the various controls on sedimentation and models the effects to be expected when these are changed outside those present in the current realm. Audience: The book is an invaluable source of information about this vast region and will be a critical reference for researchers, graduate students, and professionals engaged in marine and environmental research. It will be of particular importance for geologists interpreting the ancient rock record.

Modern seismic data have become an essential toolkit for studying carbonate platforms and reservoirs in impressive detail. Whilst driven primarily by oil and gas exploration and development, data sharing and collaboration are delivering fundamental geological knowledge on carbonate systems, revealing platform geomorphologies and how their evolution on millennial time scales, as well as kilometric length scales, was forced by long-term eustatic, oceanographic or tectonic factors. Quantitative interrogation of modern seismic attributes in carbonate reservoirs permits flow units and barriers arising from depositional and diagenetic processes to be imaged and extrapolated between wells. This volume reviews the variety of carbonate platform and reservoir characteristics that can be interpreted from modern seismic data, illustrating the benefits of creative interaction between geophysical and carbonate geological experts at all stages of a seismic campaign. Papers cover carbonate exploration, including the uniquely challenging South Atlantic pre-salt reservoirs, seismic modelling of carbonates, and seismic indicators of fluid flow and diagenesis.