Evolution of the southern Tyrrhenian slab tear and active tectonics along the western edge of the Tyrrhenian subducted slab
Published:January 01, 2009
Andrea Argnani, 2009. "Evolution of the southern Tyrrhenian slab tear and active tectonics along the western edge of the Tyrrhenian subducted slab", Collision and Collapse at the Africa–Arabia–Eurasia Subduction Zone, D. J. J. Van Hinsbergen, M. A. Edwards, R. Govers
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The evolution of the southern Tyrrhenian subduction has been possibly controlled by distinct episodes of slab break-off as indicated by a critical review of the geological literature and by the analysis of purposely acquired multichannel seismic profiles. Within the proposed interpretation the first episode occurred from 8.5 to 4.0 Ma and affected the segment of the slab located in the Sardinia Channel, causing the abandonment of the Adventure thrust front in western Sicily. The second episode occurred between 2.5 and 1.6 Ma, affecting the segment of slab located north of Sicily, and was preceeded by rifting in the Strait of Sicily. The space and time location of these episodes appear controlled by discontinuities pre-existing within the subducted African plate that trend at high angle to the advancing subduction front. These discontinuities delimit segment of subducted slab that can be affected by slab break-off and can act as wayouts for magma and mantle derived He. The major of these discontinuities, the Malta Escarpment, has been reactivated in the Quaternary as a trench-perpendicular tear (STEP faults). Ultimately, the hierarchy in strength of these trench-perpendicular features could have affected the timing and amount of trench retreat and backarc opening.
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Collision and Collapse at the Africa–Arabia–Eurasia Subduction Zone
The Mediterranean and northern Arabian regions provide a unique natural laboratory to constrain geodynamics associated with arc–continent and continent–continent collision and subsequent orogenic collapse by analysing regional and temporal distributions of the various elements in the geological archive. This book combines thirteen new contributions that highlight timing and distribution of the Cretaceous to Recent evolution of the Calabrian, Carpathian, Aegean and Anatolian segments of the Africa–Arabia–Eurasia subduction zone. These are subdivided into five papers documenting the timing and kinematics of Cretaceous arc–continent collision, and Eocene and Miocene continent–continent collision in Anatolia, with westward extrusion of Anatolia as a result. Eight papers provide an overview and new data from stratigraphy, structure, metamorphism and magmatism, covering the geological consequences of the largely Neogene collapse that characterizes the segments of interest, in response to late stage reorganization of the subduction zone, and the roll-back and break-off of (segments of) the subducting slab.