The Geology Of Cornwall
Edited by E.B. Selwood, E.M. Durrance and C.M. Bristow
Cornwall is renowned for the diversity and complexity of its geology. This geology, and its relation to the mineral wealth of the county, has been the subject of continuing investigation since the end of the seventeenth century. A literature of great historical interest exists, and this is analysed in The Geology of Cornwall alongside a wide-ranging review of the current position and assessments of the environmental consequences of rock and mineral exploitation.
These contributions by twenty-one leading academic and commercial geologists are aimed at all readers with an amateur or professional interest in exploring the fascinating geology of Cornwall. Undergraduate fieldworkers will find the book particularly helpful.
J. R. Andrews, K. Atkinson, C.M. Bristow, Roger Burt, R. A. Cullingford, E.M. Durrance, R. P. Edwards, P. Granger, M. B. Hart, M. J. Heath, K. P. Issac, F. W. A. A. Lucas, D. A. C. Manning, D. Robinson, R. C. Scrivener, E.B. Selwood, R. K. Shail, T. J. Shepherd, J. M. Thomas and J. Willis-Richards
List of Plates, x; List of Figures, xi; List of Tables, xiv; Contributors, xv; Abbreviations, xvi; Preface-Geological Field Work, xvii; A Code for Geological Field Work, xviii; Acknowledgements, xxi; CHAPTER ONE-INTRODUCTION C.M. Bristow, E.M. Durrance and E.B. Selwood, 1; Historical Review, 4; Summary of Geological Development, 5; CHAPTER TWO-THE PRE-DEVONIAN TECTONIC FRAMEWORK E.M. Durrance, 16; CHAPTER THREE-THE LIZARD COMPLEX J.R. Andrews, 21; Geological Setting, 21; The Crousa Downs Ophiolite, 23; The Western Tectonic Unit, 26; Age, 28; Ridge-Axis Tectonics, 29; Emplacement/Obduction, 30; CHAPTER FOUR-DEVONIAN, 31; K.P. Isaac, E.B. Selwood and R.K. Shail; Lower Devonian: R.K. Shail, 34; Gramscatho Basin: R.K. Shail, 40; Trevone Basin: E.B. Selwood, 48; Liskeard High: E.B. Selwood, 55; South Devon Basin: K.P. Isaac, 56; CHAPTER FIVE-CARBONIFEROUS K.P. Isaac and J.M. Thomas, 65; South of the Culm Basin: K.P. Isaac, 66; Culm Basin: J.M. Thomas, 76. CHAPTER SIX-VARISCAN STRUCTURE AND REGIONAL METAMORPHISM J.R. Andrews, K.P. Isaac, E.B. Selwood, R.K. Shail and J.M. Thomas, 82; Intrabasinal Shelf: R.K. Shail, 82; Gramscatho Basin: R.K. Shail, 87; Trevone Basin: E.B. Selwood and J.M. Thomas, 95; Liskeard High: E.B. Selwood, 102; The Structure of East Cornwall: K.P. Isaac, 103; Culm Basin: J.R. Andrews, 111; The Boscastle-Tintagel-Tregardock Culmination: J.R. Andrews, 113; Metamorphism: D. Robinson, 114; CHAPTER SEVEN-GRANITES AND ASSOCIATED IGNEOUS ACTIVITY D.A.C. Manning, 120; Granitic Rock Types, 121; Alteration of the Granites, 125; Rhyolite Porphyry Dykes (Elvans), 125; Kingsand Rhyolites, 126; Lamprophyres, 127; Compositional Variation, 127; Geochronological Data, 133; Petrogenetic Models, 134; CHAPTER EIGHT-MINERALIZATION R.C. Scrivener and T.J. Shepherd, 136; Nature of Deposits, 137; Pre-granite Mineralization, 144; Granite Related Mineralization, 147; Post-granite Mineralization, 152; Chronology of Mineralization, 153; South Crofty Mine, 155; CHAPTER NINE-MODELLING THE MINERALIZATION FRAMEWORK F.W.A.A. Lucas and J. Willis-Richards, 158; Cataclastic Flow and Lode Formation, 158; Heat Flow, 160; Convection Modelling, 162; Metasomatic Zoning of Greisen-Bordered Veins, 163; Fracture Propagation in Endo-granitic Sheeted Vein Systems, 165; CHAPTER TEN-CHINA CLAY C.M. Bristow, 167; Historical Development of Cornish China Clay Production, 167; The Formation of China Clay, 168; Mineralogy and Properties of Kaolinized Granite, 175; Resources, 177; CHAPTER ELEVEN-OFFSHORE AND MESOZOIC GEOLOGY M.B. Hart, 179; Basement Geology, 179; Post-Carboniferous Development, 181; Mesozoic History, 182; CHAPTER TWELVE-THE TERTIARY K. Atkinson, 188; Eocene, 188; Oligocene and Miocene, 191; Pliocene, 196; Tertiary Weathering Phenomena, 198; CHAPTER THIRTEEN-THE QUATERNARY R.A. Cullingford, 199; Glacial Phenomena, 199; Periglacial Phenomena, 203; Sea-level Changes, 207; Palaeobotany, 208; The Quaternary Sequence, 209; CHAPTER FOURTEEN-HISTORY OF METALLIFEROUS MINING R. Burt, 211; Early Tin Mining, 211; The Beginnings of Copper Mining, 214; Lead and Silver Production, 215; The Diversification of Output, 216; Competition and Decline, 218; Contraction and Collapse, 219; International Action, 221; Estimates of Total Output, 224; CHAPTER FIFTEEN-THE CONTEMPORARY EXTRACTIVE INDUSTRY C.M. Bristow, 226; Metalliferous Mineral Production, 226; Development of the China Clay and Chinastone Industries, 229; Raw Materials for the Construction Industries, 231; CHAPTER SIXTEEN-ENVIRONMENTAL GEOLOGY R.P. Edwards, P. Grainger and M.J. Heath, 235; Hydrology and Water Quality: M.J. Heath, 236; Environmental Impact of Metalliferous Mining: R.P. Edwards, 237; Radon: M.J. Heath, 240; Engineering Geology: P. Grainger, 243; Appendix-Geological and Geomorphological Conservation Sites; C.M. Bristow, 249; References, 263; Subject Index, 285; Locality Index, 294.
"A useful book for an introduction to Cornish geology." (OUGS Journal, 22(1), Spring 2001) "Altogether this is a most informative and readable book, and the paperback version is very reasonably priced. It is recommended for anyone who wishes to gain an informed up-to-date introduction to the geology of this geologically complex, yet historically important area." (Mineralogical Magazine October 1999)
C.M. Bristow is Visiting Professor in Industrial Geology, Camborne School of Mines. E.B. Selwood is Senior Lecturer in Earth Science, University of Exeter. E. M. Durrance is Emeritus Professor of Geology, University of Nebraska
The Geology Of Cornwall - Hardback cover