The late rifting phase and continental break-up of the southern South Atlantic: the mode and timing of volcanic rifting and formation of earliest oceanic crust
Published:January 01, 2016
H. Koopmann, B. Schreckenberger, D. Franke, K. Becker, M. Schnabel, 2016. "The late rifting phase and continental break-up of the southern South Atlantic: the mode and timing of volcanic rifting and formation of earliest oceanic crust", Magmatic Rifting and Active Volcanism, T. J. Wright, A. Ayele, D. J. Ferguson, T. Kidane, C. Vye-Brown
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Multichannel seismic and potential field data shed light on the final rifting stage in the southern South Atlantic. This was associated with major episodes of magmatism during the Early Cretaceous continental break-up. An asymmetrical simple shear-dominated variable strain rifting model is proposed with the margin asymmetry visible in shelf width, amplitude of magnetic anomalies, orientation of break-up-related sedimentary basins and basement slope angle. Along-margin rotation in spreading- and later rifting-direction from north–south to west–east are of great importance for the asymmetries. Such rotational opening may also explain why the southernmost segments of the South Atlantic are magma starved, with...
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Magmatic Rifting and Active Volcanism
A major rifting episode began in the Afar region of northern Ethiopia in September 2005. Over a ten-day period, c. 2.5 km3 of magma were intruded along a 60 km-long dyke separating the Arabian and Nubian plates. Over the next five years, a further 13 dyke intrusions caused continued extension, eruptions and seismicity. This activity led to a renewed international focus on the role of magmatism in rifting, with major international collaborative projects working in Afar and Ethiopia to study the ongoing activity and to place it in a broader context. This book brings together articles that explore the role of magmatism in rifting, from the initiation of continental break-up through to full seafloor spreading. We also explore the hazards related to rifting and the associated volcanism. This work has implications for our understanding of how continents break-up and the associated distribution of resources in rift basins and continental margins.