B.W. Sellwood – författare

At many times in the geological past the climate of the Earth appears to have been significantly different from that at the present time. Some of the consequences of the Quaternary "icehouse" are beginning to be better understood. However, during the Mesozoic era our planet appears to have been generally more equable (a"greenhouse earth"). Crucial evidence for the existence of major continental ice-caps and associated tundra zones is lacking. The purpose of this book is to faciliate the integration of available geological information - the incomplete evidence relating to Mesozoic palaeoclimates - with insights that may be derived from climate modelling of a meteorological character (e.g. GCM's). By such an integration of meteorological and geological approaches future patterns of possible climate change, and the localized consequences of such changes, may be better predicted. The book shows what can begin to be achieved when information, techniques and insights from a wide range of fields are considered together.The juxaposition of climate modelling, geological collations and interrelational interpretations should make this book of particular use to researchers and postgraduate students working and teaching in the broad areas of environmental studies and climate change, as well as others in the more conventional areas of the Earth and atmospheric sciences. This book should be of interest to postgraduates and researchers in earth science, geography and environmental sciences; particularly in palaeoclimatology and climate modelling.

Reservoirs generally consist of sandstones or carbonates exhibiting heterogeneities caused by a wide range of factors. Some of these formed depositionally (eg. as channels, palaeosols, clay seams or salts), others may be diagenetic in origin (eg. carbonate or silica cemented zones, authigenic clays, karstic surfaces). The severity with which diagenesis affects rock systems results from the interplay between the diagenetic process itself and the timescale over which it operated. This text provides a wide-ranging overview of diagenetic processes and responses in calcareous, argillaceous, arenaceous and carbon-rich (microbial and organic) sedimentary systems. It introduces diagenetic concepts, reviews existing knowledge and shows how existing qualitative approaches might be developed in more quantitative ways. Several chapters consider mass balance calculations and the temporal and spatial aspects of diagenetic processes. It provides a source reference for advanced students and professionals active in reservoir and aquifer studies.

The topic of sediment diagenesis is of fundamental importance to industry in the evaluation of hydrocarbon and water reservoir rocks. Detailed knowledge of the diagenetic textures, fabrics, and minerals, and a prediction of the regional diagenetic response, partly controls hydrocarbon recovery programmes. In other words, knowledge of the diagenesis can aid (or even control) conservation policy. Similarly, facies and diagenetic trends w.ithin basins can influence exploration policy. This volume incorporates the majority of the principal contributions given to the NATO Advanced Study Institute held in the University of Reading, U.K., from July 12th-25th, 1981, at which the major themes of carbonate and terrigenous clastic sediments were treated sequentially from deposition to deep burial. Eighty selected scientists from twelve NATO and three other countries participated in the Institute. The keynote addresses which acted as the touchstones for discussion are presented here in the expectation that they will stimulate a still wider audience. We gratefully acknowledge the award of a grant from the Scientific Affairs Division of NATO to run the Institute, and also the cooperation of the University of Reading. Mrs. D. M. Powell helped in many ways with the organisation, and also retyped the entire manuscript of this book. A. Parker B. lv. Sellwood vii FACIES, SEQUENCES AND SAND-BODIES OF THE PRINCIPAL CLASTIC DEPOSITIONAL ENVIRONMENTS T.Elliott Department of Geology University College of Swansea Singleton Park, Swansea SA 2 8PP Wales, U.K.

Reservoirs generally consist of sandstones or carbonates exhibiting heterogeneities caused by a wide range of factors. Some of these formed depositionally (e.g. as channels, palaeosols, clay seams or salts), others may be diagenetic in origin (e.g. carbonate or silica cemented zones, authigenic clays, karstic surfaces). The severity with which diagenesis affects rock systems results from the interplay between the diagenetic process itself and the timescale over which it operated. The book provides a wide-ranging overview of diagenetic processes and responses in calcareous, argillaceous, arenaceous and carbon-rich (microbial and organic) sedimentary systems. It introduces diagenetic concepts, reviews existing knowledge, and shows how existing qualitative approaches might be developed in more quantitative ways. Several chapters consider mass balance calculations and the temporal and spatial aspects of diagenetic processes. It is unique, as a textbook, in providing such a breadth of diagenetic subject range and such depth of coverage in each topic. It provides a source reference for advanced students and professionals active in reservoir and aquifer studies.