Outer Cilicia Basin – A piggy back basin developed in an intramontane setting following the partitioning of a large ancestral Miocene basin across the northeastern Mediterranean

• Published in: Tectonophysics 2021-09, Vol.814, p.228952, Article 228952
• Main Authors: Aksu, A.E., Yaltırak, C., Hall, J.
• Format: Article
• Language: English
• Subjects: Basins; Central Taurus Mountains; Dipping; Eastern Mediterranean; Evaporites; Fault lines; Fault zones; Geological faults; Graben; Hanging walls; Messinian; Miocene; Mountains; Mut Basin; Outer Cilicia Basin; Partitioning; Quaternary; Regional tectonics; Seismic reflection profiles; Seismic stratigraphy; Seismic surveys; Strike-slip faults; Tectonics
• ISSN: 0040-1951; 1879-3266
• DOI: 10.1016/j.tecto.2021.228952

Multichannel seismic reflection profiles show that the Outer Cilicia Basin evolved mainly during the uppermost Messinian–Quaternary as an asymmetric piggyback basin on the hanging wall of the large south-verging Kyrenia thrust culmination, following the partitioning of the much larger Miocene basin. A major north-verging backthrust and several similarly-verging smaller splays developed during the deposition of the uppermost Messinian–Quaternary succession, elevating the southern sector of the Outer Cilicia Basin ~250–500 ms above the central portion of the basin. An E–W trending zone characterized by 6–9 positive flower structures which are cored by the Messinian evaporite successions developed immediately north of the backthrust. Two prominent broadly E–W striking extensional fault zones define the tectonic framework of the north and south margins of the basin: (a) the Zafer–Kormakiti zone in the south with 5–6 internally parallel and invariably north-dipping large listric extensional faults developed immediately north of the Kyrenia Range and (b) the Anamur–Silifke zone in the north with 4–8 internally parallel and steeply north- and south-dipping planar faults defining a series of shore-parallel horst and graben structures developed immediately south of the Central Taurus Mountains. The Zafer–Kormakiti and the Anamur–Silifke fault zones are shown to be the westward extensions of the uppermost Messinian–Quaternary Misis–Kyrenia and Kozan fault zones, respectively. The tectonic framework of the Miocene successions across the Mut Basin delineated using >310 strike and dip measurements extracted from 1:25,000–1:100,000 maps supplemented by >1200 strike and dip determinations using the rule of Vs and construction of structure contours. These data revealed two distinct regional folds, where the anticlinal and synclinal axes are oriented WNW–ESE and NE–SW directions. Geological cross sections constructed suggest that the folds are likely cored by broadly southerly verging deep-seated blind thrusts. •A large ancestral Miocene basin became partitioned during the Pliocene–Quaternary.•During the Messinian Outer Cilicia Basin was periodically inundated by the sea.•Pliocene–Quaternary strain was spatially partitioned into five E–W oriented zones.•Miocene successions in Mut Basin exhibit WNW–ESE and NE–SW oriented folds.