The Galapagos

The Galápagos Islands are renown for their unique flora and fauna, inspiring Charles Darwin in the elaboration of his theory of evolution. Yet in his Voyage of the Beagle, published in 1839, Darwin also remarked on the fascinating geology and volcanic origin of these enchanted Islands. Since then, the Galápagos continue to provide scientists with inspiration and invaluable information about ocean island formation and evolution, mantle plumes, and the deep Earth.

Motivated by an interdisciplinary Chapman Conference held in the Islands, this AGU volume provides cross-disciplinary collection of recent research into the origin and nature of ocean islands, from their deepest roots in Earth's mantle, to volcanism, surface processes, and the interface between geology and biodiversity.

Volume highlights include:

• Case studies in biogeographical, hydrological, and chronological perspective
• Understanding the connection between geological processes and biodiversity
• Synthesis of decades of interdisciplinary research in physical processes from surface to deep interior of the earth
• In-depth discussion of the concept of the island acting as a natural laboratory for earth scientists
• Integrated understanding of the Galápagos region from a geological perspective

Collectively, The Galápagos presents case studies illustrating the Galápagos Archipelago as a dynamic natural laboratory for the earth sciences. This book would be of special interest to a multidisciplinary audience in earth sciences, including petrologists, volcanologists, geochronologists, geochemists, and geobiologists.

Auteur

Karen Harpp is a geochemist and volcanologist in the Geology Department at Colgate University, in upstate New York, USA. She and her students have been exploring the Galápagos for many years, studying the origins of the volcanic islands across the archipelago using land- and sea-based research methods.

Eric Mittelstaedt is a geodynamicist and geophysicist in the Department of Geological Sciences at the University of Idaho. Using geophysical data, and numerical and analogue experiments, he studies the interactions between mantle dynamics, and surface tectonics and volcanism in the Earth's ocean basins.

David Graham is an isotope geochemist in the College of Earth, Ocean, and Atmospheric Sciences at Oregon State University. He specializes in using noble gas measurements of volcanic rocks from the oceans and continents to investigate geodynamics of the Earth's mantle.

Noémi d'Ozouville is a post-doc at the University Pierre et Marie Curie, Paris 6, France. She lives in the Galápagos Islands where her research activities include the hydrology and hydrogeology of volcanic ocean islands through a combined approach of remote sensing, geophysical data and hydro-climatological monitoring, data collection, and analysis. She continues to play an important role in conservation and water management in the islands. She now works at the Charles Darwin Research Station as Science Administrator.

Contenu

Contributors vii

Foreword: Darwin's Perspective
Randal Keynes xi

Foreword: The Galápagos as a Natural Laboratory
Peter Grant xiii

Acknowledgments xv

1. Introduction
   Eric Mittelstaedt, Noémi d'Ozouville, Karen S. Harpp, and David W. Graham 1

2. Contrasting Volcanism in Hawai'i and the Galápagos
   Michael P. Poland 5

3. Galápagos and Easter: A Tale of Two Hotspots
   Karen S. Harpp, Paul S. Hall, and Matthew G. Jackson 27

4. Eruption Rates for Fernandina Volcano: A New Chronology at the Galápagos Hotspot Center
   Mark D. Kurz, Scott K. Rowland, Joshua Curtice, Alberto E. Saal, and Terry Naumann 41

5. Galápagos Magma Chambers
   Dennis J. Geist, George Bergantz, and William W. Chadwick, Jr 55

6. The Geology and Geochemistry of Isla Floreana, Galápagos: A Different Type of Late-Stage Ocean Island Volcanism
   Karen S. Harpp, Dennis J. Geist, Alison M. Koleszar, Branden Christensen, John Lyons, Melissa Sabga, and Nathan Rollins 71

7. Plate Tectonics, Evolution, and the Survival of Species: A Modern Day Hotspot
   Godfrey Merlen 119

8. A Paleogeographic Model of the Galápagos Islands and Biogeographical and Evolutionary
   Implications
   Dennis J. Geist, Howard Snell, Heidi Snell, Charlotte Goddard, and Mark D. Kurz 145

9. Hydrogeology of the Galápagos Archipelago: An Integrated and Comparative Approach Between Islands
   Sophie Violette, Noémi d'Ozouville, Alexandre Pryet, Benoît Deffontaines, Jérôme Fortin, and
   Mathilde Adelinet 167

10. Controls on the Hydrological and Topographic Evolution of Shield Volcanoes and Volcanic Ocean Islands
    Anne J. Jefferson, Ken L. Ferrier, J. Taylor Perron, and Ricardo Ramalho 185

11. Climate and the Global Reach of the Galápagos Archipelago: State of the Knowledge
    Kristopher B. Karnauskas, Raghu Murtugudde, and W. Brechner Owens 215

12. Assessment of the Chile 2010 and Japan 2011 Tsunami Events in the Galápagos Islands
    Willington Rentería and Patrick Lynett 233

13. Patterns in Galápagos Magmatism Arising from the Upper Mantle Dynamics of Plume-Ridge
    Interaction
    Garrett Ito and Todd Bianco 245

14. Variations in Crustal Thickness, Plate Rigidity, and Volcanic Processes Throughout the Northern Galápagos Volcanic Province
    Eric Mittelstaedt, Adam S. Soule, Karen S. Harpp, and Daniel Fornari 263

15. Plume-Ridge Interaction in the Galápagos: Perspectives from Wolf, Darwin, and Genovesa Islands
    Karen S. Harpp, Karl R. Wirth, Rachel Teasdale, Susanna Blair, Leslie Reed, Jay Barr, Janna Pistiner,
    and Daniel Korich 285

16. A Preliminary Survey of the Northeast Seamounts, Galápagos Platform
    Christopher W. Sinton, Karen S. Harpp, and David M. Christie 335

17. Effect of Variations in Magma Supply on the Crustal Structure of Mid-Ocean Ridges: Insights from the Western Galápagos Spreading Center
    Juan Pablo Canales, Robert A. Dunn, Garrett Ito, Robert S. Detrick, and Valentí Sallarès 363

18. Helium Isotope Variations and Mantle Plume-Spreading Ridge Interactions Along the Galápagos Spreading Center
    David W. Graham, Barry B. Hanan, John E. Lupton, Kaj Hoernle, Reinhard Werner, David M. Christie, and John M. Sinton 393

Index 415