The Calabrian Arc (CA) subduction system is part of the complex African-Eurasian plate boundary in the central Mediterranean Sea and connects the NW/SE trending Apennine with the E-W trending Magrebian thrust belt. Previous studies have outlined the overall architecture of the subduction complex in the Ionian Sea through the analysis of high penetration seismic lines (Cernobori et al., 1996; Doglioni et al. 1999; Finetti, 2005). None of these studies focuses on the outermost part of the CA system, i.e. the transition between the accretionary wedge and the Ionian abyssal plain, and we believe this is the reason why a major question remains unanswered: “is the CA subduction still active”? The lack of seismicity along the subduction fault plane (with a characteristic shallow dipping thrust-type focal mechanism) can be explained by one of the following occurrences: 1) subduction has ceased; 2) subduction is active but aseismically, or 3) subduction is active and there is a large locked seismogenic zone. Diverse earthquake scenarios can be envisioned depending on which of these three hypotheses is taken into account. Understanding the present-day tectonics of the CA is thus important to understand the geological risk in central Mediterranean region.
Polonia A., Torelli L., Capozzi R., Riminucci F., Artoni A., Ramella R., et al. (2008). African/Eurasian plate boundary in the Ionian Sea: shortening and strike slip deformation in the outer Calabrian Arc accretionary wedge.. TRIESTE : Stella Arti Grafiche, Trieste.
African/Eurasian plate boundary in the Ionian Sea: shortening and strike slip deformation in the outer Calabrian Arc accretionary wedge.
CAPOZZI, ROSSELLA;
2008
Abstract
The Calabrian Arc (CA) subduction system is part of the complex African-Eurasian plate boundary in the central Mediterranean Sea and connects the NW/SE trending Apennine with the E-W trending Magrebian thrust belt. Previous studies have outlined the overall architecture of the subduction complex in the Ionian Sea through the analysis of high penetration seismic lines (Cernobori et al., 1996; Doglioni et al. 1999; Finetti, 2005). None of these studies focuses on the outermost part of the CA system, i.e. the transition between the accretionary wedge and the Ionian abyssal plain, and we believe this is the reason why a major question remains unanswered: “is the CA subduction still active”? The lack of seismicity along the subduction fault plane (with a characteristic shallow dipping thrust-type focal mechanism) can be explained by one of the following occurrences: 1) subduction has ceased; 2) subduction is active but aseismically, or 3) subduction is active and there is a large locked seismogenic zone. Diverse earthquake scenarios can be envisioned depending on which of these three hypotheses is taken into account. Understanding the present-day tectonics of the CA is thus important to understand the geological risk in central Mediterranean region.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
