Mid-Ocean Ridges (Dynamics of Processes Associated with the Creation of New Oceanic Crust)

This book collects multidisciplinary chapters on the most important problems that arise at mid-ocean ridges. The mid-ocean ridge system is the longest continuous feature of the earth's surface. It is where the great majority of ocean floor is created and volumes of seafloor volcanism vastly exceed those on land. It provides the means for much of the heat loss from the interior of the earth. Chemicals as well as heat are extracted by flowing seawater through the rocks of the seafloor, leading to spectacular areas of hydrothermal venting, that affect ocean chemistry and global climate. The chapters range from studies of the mantle and magma generation within it, through tectonics of mid-ocean ridges, to the physical, chemical and biological dynamics of hydrothermal systems. The book will be of importance to specialists and researchers wishing to become informed of the latest developments in the science of mid-ocean ridges. It will prove especially useful for new scientists entering the field. Contents......Page 6 Preface......Page 8 Sensitivity of teleseismic body waves to mineral texture and melt in the mantle beneath a mid-ocean ridge......Page 10 Evidence for accumulated melt beneath the slow-spreading Mid-Atlantic Ridge......Page 26 An analysis of variations in isentropic melt productivity......Page 48 A review of melt migration processes in the adiabatically upwelling mantle beneath oceanic spreading ridges......Page 76 Rift-plume interaction in the North Atlantic......Page 112 The ultrafast East Pacific Rise: instability of the plate boundary and implications for accretionary processes......Page 133 Seafloor eruptions and evolution of hydrothermal fluid chemistry......Page 160 Controls on the physics and chemistry of seafloor hydrothermal circulation......Page 178 Where are the large hydrothermal sulphide deposits in the oceans?......Page 218 Sea water entrainment and fluid evolution within the TAG hydrothermal mound: evidence from analyses of anhydrite......Page 232 Thermocline penetration by buoyant plumes......Page 256 Crustal accretion and the hot vent ecosystem......Page 272 Biocatalytic transformations of hydrothermal fluids......Page 288 Index......Page 300 This book collects together multidisciplinary chapters on the most important problems that arise at mid-ocean ridges. The mid-ocean ridge system is the longest continuous feature of the earth's surface, at which the great majority of ocean floor is created, and volumes of seafloor volcanism vastly exceed those on land. It provides the means for much of the heat loss from the interior of the earth. Chemicals as well as heat are extracted by flowing seawater through the rocks of the seafloor, leading to spectacular areas of hydrothermal venting, affecting ocean chemistry and global climate. The chapters range from studies of the mantle and magma generation within it, through tectonics of mid-ocean ridges, to the physical, chemical and biological dynamics of hydrothermal systems. The book will be of importance to specialists and researchers wishing to become informed of the latest developments in the science of mid-ocean ridges. It will prove especially useful for new scientists entering the field Seismic energy propagating through the mantle beneath an oceanic spreading centre develops a signature due both to the subaxial deformation field and to the presence of melt in the upwelling zone.