Oceanic Hotspots

Ocean Hotspots provides a comprehensive overview of recent and ongoing research on intraplate volcanism in the ocean basins with special emphasis on the Pacific Ocean. The geology of the seamounts and their associated seamount chains is described, along with detailed geophysical, geochemical and hydrothermal observations made by a multi-disciplinary group of marine geoscientists. These observations lead to a deeperunderstanding of how the ascending mantle melts, represented by hotspots, are able to penetrate the lithosphere, build seamounts, and enhance hydrothermal circulation. The "fixed" hotspot-generated seamount chains also provide key constraints on plate tectonic reconstructions on the Earth's crust.

References. - 1 Sea-Floor Topography and Morphology of the Superswell Region. - 1. 1 Introduction. - 1. 2 Data Sources and Methods. - 1. 3 Sea-floor Morphology in French Polynesia. - 1. 4 Conclusions. - Acknowledgements. - References. - 2 Seismicity of the Society and Austral Hotspots in the South Pacific: Seismic Detection, Monitoring and Interpretation of Underwater Volcanism. - 2. 1 Introduction. - 2. 2 Seismic Waves Used. - 2. 3 Volcano-Seismic Activities on the Society Hotspot. - 2. 4 Volcano-Seismic Activity of the Austral Hotspot: Macdonald Seamount. - 2. 5 Summary and Conclusions. - Acknowledgements. - References. - 3 A Global Isostatic Load Model and its Application to Determine the Lithospheric Density Structure of Hotspot Swells. - 3. 1 Introduction. - 3. 2 Isostasy of the Lithospheric Plate. - 3. 3 Reference Model. - 3. 4 Lithospheric Density Structure of Hotspot Swells. - 3. 5 Subsidence of Hotspot Structures. - 3. 6 Conclusions. - Acknowledgements. - References. - 4 Origin of the 43 Ma Bend Along the Hawaiian-Emperor Seamount Chain. - 4. 1 Introduction. - 4. 2 The Emperor Seamount Chain Paradox. - 4. 3 The Origin of the 43Ma Bend. - 4. 4 Summary and Conclusion. - Acknowledgements. - References. - 5 South Pacific Intraplate Volcanism: Structure, Morphology and Style of Eruption. - 5. 1 Introduction. - 5. 2 Society Hotspot. - 5. 3 Austral Hotspot. - 5. 4 Pitcairn Hotspot. - 5. 5 Hotspot Versus Non-Hotspot Volcanoes. - 5. 6 Style of Eruption and Formation of Hotspot Edifices. - 5. 7 Summary and Conclusions. - Acknowledgements. - References. - 6 Submarine Landslides in French Polynesia. - 6. 1 Introduction. - 6. 2 Geological Setting. - 6. 3 Landslides of the Society Islands. - 6. 4 Austral Island Landslides. - 6. 5 Classification of the Society and Austral Landslides. - 6. 6 Evolution of the Mass Wasting with the Age of the Edifices. - 6. 7Conclusion. - Acknowledgements. - References. - 7 Mantle Plumes are NOT From Ancient Oceanic Crust. - 7. 1 Introduction. - 7. 2 Petrological Arguments. - 7. 3 Geochemical Arguments. - 7. 4 Mineral Physics Arguments. - 7. 5 Summary. - Acknowledgements. - References. - 8 The Sources for Hotspot Volcanism in the South Pacific Ocean. - 8. 1 Introduction. - 8. 2 The Hotspot Chains of the South East Pacific. - 8. 3 Discussion: Petrogenesis of South East Pacific Hotspots. - Acknowledgements. - References. - 9 Plume-Ridge Interactions: New Perspectives. - 9. 1 Introduction. - 9. 2 Concepts. - 9. 3 Examples. - 9. 4 Summary and Conclusion. - Acknowledgements. - References. - 10 Intraplate Gabbroic Rock Debris Ejected from the Magma Chamber of the Macdonald Seamount (Austral Hotspot): Comparison with Other Provinces. - 10. 1 Introduction. - 10. 2 The Macdonald Seamount. - 10. 3 Petrology. - 10. 4 Geochemistry. - 10. 5 Discussion. - 10. 6 Summary and Conclusions. - Acknowledgements. - References. - 11 The Foundation Chain: Inferring Hotspot-Plate Interaction from a Weak Seamount Trail. - 11. 1 Introduction. - 11. 2 Sample Preparation and Analytical Procedure. - 11. 3 Results. - 11. 4 Discussion. - 11. 5 Conclusions. - Acknowledgements. - References. - 12 Hydrothermal Iron and Manganese Crusts from the Pitcairn Hotspot Region. - 12. 1 Introduction. - 12. 2 Geological Setting. - 12. 3 Sample Description. - 12. 4 Chemical Composition. - 12. 5 Formation of Fe and Mn Crusts. - 12. 6 Conclusions. - Acknowledgements. - References. - 13 Methane Venting into the Water Column Above the Pitcairn and the Society-Austral Seamounts, South Pacific. - 13. 1 Introduction. - 13. 2 Geological Setting. - 13. 3 Methods. - 13. 4 Results and Discussion. - 13. 5 Conclusions. - Acknowledgements. - References. - 14 Petrology of Young Submarine Hotspot Lava: Composition and Classification. - 14. 1 Introduction. - 14. 2 Composition and Description of Oceanic Rocks. - 14. 3 Relationship Between Intraplate-Hotspot and Spreading-Ridge Magmatism. - 14. 4 Compositional Differences Among Hotspots. - 14. 5 Summary and Conclusions. - Acknowledgements. - References.