Evolution and architecture of the Hellenic Arc - Cyprus Arc junction in the eastern Mediterranean

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This study aims to investigate the tectonic and sedimentary evolution of the Hellenic Arc-Cyprus Arc junction in the eastern Mediterranean Sea over the last 25 million years using high-resolution marine multi-channel seismic reflection profiles. The two arcs form the active convergent boundary between the African and Aegean-Anatolian plates. The Hellenic Arc is still an active subduction zone, rolling back to the south, while the subducting African plate dips down below it to the north. The Cyprus Arc is moving much more slowly southwards relative to the African plate. This part of the plate boundary is in transition from subduction to continental collision. Thus, the Hellenic Arc is moving southwards relative to the Cyprus Arc, with the relative motion accommodated by a sinistral transform, which is the focus of this study. The key question is "how do such arc junctions behave? We know they are sites of extreme topography, presumably caused by stress build up at corners. But, the tectonic evolution and its impact on the record of sediments deposited at sea is not well understood. The study area includes the southern portion of the Rhodes Basin, the Anaximander Mountains and the western portion of the Florence Rise. It is the most accessible place to answer these questions, with good knowledge of surrounding geology. The marine areas provide outstanding subsurface seismic images that enable our group to examine the tectonic and sedimentary evolution and determine and the changes in stress orientations during the last 25 million years associated with plate convergence. Our group will test various hypotheses related to the development of extreme relief at the arc-arc junction (Rhodes Basin and Anaximander Mountains), the transfer of thick crustal blocks (Anaximander Mountains) from lower to upper plate as plate convergence proceeds, the behavior of salt in compressional basins (Florence Rise, Antalya Basin), and the timing of dewatering in accretionary wedges (Mediterranean Ridge, Florence Rise) as their stress systems change from compression to transtension.