The Central Atlantic Magmatic Province

Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 136. A singular event in Earth's history occurred roughly 200 million years ago, as rifting of the largest and most recent supercontinent was joined by basaltic volcanism that formed the most extensive large igneous province (LIP) known. A profound and widespread mass extinction of terrestrial and marine genera occurred at about the same time, suggesting a causal link between the biological transitions of the Triassic-Jurassic boundary and massive volcanism. A series of stratigraphic, geochronologic, petrologic, tectonic, and geophysical studies have led to the identification of the dispersed remnants of this Central Atlantic Magmatic Province (CAMP) on the rifted margins of four continents. Current discoveries are generally interpreted to indicate that CAMP magmatism occurred in a relative and absolute interval of geologic time that was brief, and point to mechanisms of origin and global environmental effects. Because many of these discoveries have occurred within the past several years, in this monograph we summarize new observations and provide an up-to-date review of the province.

Preface Willis E. Hames, J. Gregory McHone, Paul R. Renne, and Carolyn Ruppel vii Introduction W. Hames, J. G. McHone, P. Renne, and C. Ruppel 1 Cyclo-, Magneto-, and Bio-Stratigraphic Constraints on the Duration of the CAMP Event and its Relationship to the Triassic-Jurassic Boundary Paul E. Olsen, Dennis V. Kent, Mohammed Et-Touhami, and John Puffer 7 Relative Timing of CAMP, Rifting, Continental Breakup, and Basin Inversion: Tectonic Significance Roy W. Schlische, Martha Oliver With jack, and Paul E. Olsen 33 Age Estimates of the Seaward-Dipping Volcanic Wedge, Earliest Oceanic Crust, and Earliest Drift-Stage Sediments Along the North American Atlantic Continental Margin Richard N. Benson 61 Critical Evaluation of 40Ar/39Ar Ages for the Central Atlantic Magmatic Province: Timing, Duration and Possible Migration of Magmatic Centers Ajoy K. Baksi  77 The Central Atlantic Magmatic Province (CAMP) in Brazil: Petrology, Geochemistry, 40Ar/39Ar Ages, Paleomagnetism, and Geodynamic Implications Angelo De Min, Enzo M. Piccirillo, Andrea Marzoli, Giuliano Bellieni, Paul R. Renne, Marcia Ernesto, and Leila S. Marques 91 Paleomagnetic and Geochemical Constraints on the Timing and Duration of the CAMP Activity in Northeastern Brazil M. Ernesto, G. Bellieni, E. M. Piccirillo, I. S. Marques, A. De Min, I. G Pacca, G. Martins, and, W. P. Macedo 129 A Reactivated Back-arc Source for CAMP Magma John H. Puffer 151 Temporal Chemical Variations Within Lowermost Jurassic Tholeiitic Magmas of the Central Atlantic Magmatic Province Vincent J. M. Salters, P. C. Ragland, W. E. Hames, K. Milla, and C. Ruppel 163 The Late Triassic-Early Jurassic Volcanism of Morocco and Portugal in the Framework of the Central Atlantic Magmatic Province: An Overview Nasrrddine Youbi, Lfnia Tavares Martins, Jose Manuel Munha, Hassan Ibouh, Jose Madeira, El Houssaine Ait Chayeb, and Abdelmajid El Boukhari 179 The Northernmost CAMP: 40Ar/39Ar Age, Petrology and Sr-Nd-Pb Isotope Geochemistry of the Kerforne Dike, Brittany, France Fred Jourdan, Andrea Marzoli, Herve Bertrand, Michael Cosca, and Denis Fontignie 209 Magma Flow Pattern in the North Mountain Basalts of the 200 Ma CAMP Event: Evidence From the Magnetic Fabric Richard E. Ernst, Jelle Zeilinga de Boer, Peter Ludwig, and Taras Gapotchenko 227 Volatile Emissions From Central Atlantic Magmatic Province Basalts: Mass Assumptions and Environmental Consequences J. Gregory McHone 241 Volcanism of the Central Atlantic Magmatic Province as a Potential Driving Force in the End-Triassic Mass Extinction Jozsef Palfy 255