Akademik Veri Yönetim Sistemi
Şubat 2023 Depremleri ve Bölgemize Etkileri, Adana, Türkiye, 28 Şubat - 01 Mart 2024, cilt.1, sa.1, ss.9-14
A good understanding of the controls of hazard in the earthquake region is aided by a knowledge of the regional geology and tectonic development.The region belongs to the Arabian (African) plate and the over-riding Tauride (Eurasian plate). The palaeogeography of the African plate was largely controlled by rifting of the S Neotethys during the Triassic. The collision of this rifted margin with the over-riding Tauride plate initiated the neotectonics of the easternmost Mediterranean and adjacent SE Turkey. The PalaeozoicMesozoic geological record of the Arabian plate is largely known from the Amanos Mountains that were uplifted and exposed during the Miocene, whereas the late MesozoicRecent is exposed much more widely along the northern margin of the Arabian plate.Initially, Precambrian-Lower Palaeozoic siliciclastic and carbonate sediments accumulated on a broad shelf bordering N Gondwana. Following Triassic rifting of S Neotethys, a Bahama-type carbonate platform developed during passive margin subsidence. During the Late Cretaceous, ophiolites formed above a subduction zone and were then obducted southwards onto the Arabian continental margin as a result of trench/passive margin collision (e.g. Hatay and Amanos ophiolites). Passive margin conditions resumed during the Paleogene when the continental margin was mainly covered by shelf carbonates. There are indications of compression related to initial continent-continent collision during the Eocene in the S Amanos Mtns. The Eurasian plate was clearly colliding with the Arabian plate during the Early Miocene, associated with large-scale southward emplacement of Tauride-derived thrust sheets over a flexurally downwarped foreland basin along the northern edge of the Arabian plate. The over-riding Tauride plate comprises a stack of thrust sheets that restore, from south to north, as the distal passive margin of the Arabian plate (Karadut Complex), deep-sea sediments, volcanics accreted from the S Neotethys (Koçali Complex), intrusive Upper Cretaceous SSZ-type ophiolitic rocks (Berit ophiolite), and Palaeozoic-Mesozoic continental crust cut by Upper Cretaceous granitoids (Malatya Metamorphics). Continuing plate convergence during Mid-Late Miocene was largely accommodated by internal shortening and uplift within the emplaced Tauride thrust wedge, culminating in a final pulse of southward thrusting and folding during the Late Miocene (possibly accompanied by progressive slab break-off). Left-lateral strike-slip along the broad array of faults related to the East Anatolian Transform Fault began during the Pliocene, continuing until Recent. To the E of the Amanos Mountains, the Karasu basin developed as a transtensional rift with basaltic eruptions and marginal alluvial fans, extending to the coast as the Hatay half-graben structure. The earthquake region is marked by displacements along two main contrasting fault trends, which bear comparison with the previously mapped pattern of Plio-Quaternary faults in the region. Overall, the above restored tectonic development shows that the earthquake-affected region developed as a dogleg in the rifted Arabian margin (Permo-Triassic), which in turn influenced the mainly Miocene collisional tectonics, and subsequently became involved in westward tectonic escape.