Tauride Block Research Articles

The Cilicia–Adana basin complex, Eastern Mediterranean: Neogene evolution of an active fore-arc basin in an obliquely convergent margin

Detailed interpretation of multi-channel seismic reflection profiles showed that the deposition of the Miocene successions in the Cilicia–Adana basin complex occurred within a foredeep, south of the arcuate Tauride fold–thrust belt. The Misis–Kyrenia fault zone defined the northernmost of a number of smaller thrust culminations developed within this foredeep. Fluvio-deltaic successions suggest that the Adana and Inner Cilicia basins became emergent during the Tortonian, when the western portion of the piggy-back basin retained a marine connection. The entire region became emergent during the Messinian salinity crisis, and up to 1000 m of evaporites were deposited in the Cilicia and southern Adana basins. Stratigraphic and structural relationships demonstrated that the late Plio-Quaternary Cilicia–Adana basin complex evolved as an asymmetric piggy-back basin on the hanging wall of the large south-verging Misis–Kyrenia thrust culmination. On the Misis–Kyrenia segment of the culmination, thrust activity ceased in early Messinian, whereas on the Kyrenia segment, it continued to the present. The shift in the kinematics is expressed by the development of the NE–SW trending steep faults with extensional separations bounding the Plio-Quaternary depocentre in the Adana and Inner Cilicia basins. These basement-rooted faults are incompatible with the contractional regime that existed in this part of the basin complex during the Miocene. In the Outer Cilicia Basin, the incompatibility between a domain of continued south-directed fold–thrust activity and uplift on the Kyrenia Range and a domain of extension associated with the development of Plio-Quaternary depocentre indicates that strain is strongly partitioned across the E–W trending southern basin-bounding fault system along the southern margin of the Outer Cilicia Basin. Progressive westward displacement of the Tauride block within the Aegean–Anatolian microplate created a localised transtensional regime within the Inner Cilicia and Adana basins, suggesting the presence of hard intra-plate fault boundaries centred along the Misis–Kyrenia horst block and the southern basin-bounding fault system. The northern basin-bounding fault system, including the Kozan fault in the Cilicia Basin, is a set of large antithetic structures linked to the master faults. The westward pull-out of the Tauride block is related to the overall westward escape of the Aegean–Anatolian microplate during the latest Miocene to early Pliocene, whereas the continued contraction south of the basin complex across Cyprus is related to the evolving collision and under-plating of the continental micro-fragment, the Eratosthenes. We propose that the southern master fault of the Outer Cilicia Basin primarily functions as a boundary separating a contractional microplate domain to the south from a transtensional microplate domain to the north.

Neogene development of the Antalya Basin, Eastern Mediterranean: An active forearc basin adjacent to an arc junction

Detailed interpretation and mapping of high-resolution multi-channel seismic reflection profiles showed a two phase history for the Miocene–Recent kinematic evolution of the Antalya Basin. The first phase of deformation occurred in the Middle–Late Miocene when a crustal-scale imbricate fold–thrust belt developed. This phase of deformation affected the entire Antalya Basin and is represented by several major northwest–southeast-striking, north-dipping and south-verging thrust culminations, which created a series of elongated to teardrop-shaped piggyback basins. The transitions from late Miocene to Messinian and Messinian to Plio-Quaternary are marked by the N- and M-reflectors which record the periods of erosion associated with the initial and final phases of desiccation of the Mediterranean Sea, respectively. A fundamental change in kinematic regime occurred during the transition from the Miocene to Plio-Quaternary. During early Pliocene to Recent the fold–thrust belt was overprinted by extensional/transtensional faults in the northeastern Antalya Basin, while transpression dominated the southwestern Antalya Basin. This tectonic phase is related to the westward displacement of the Tauride block as the eastern segment of the Aegean–Anatolian Microplate initiated its westward escape in the latest Miocene to early Pliocene.

Origin of the Eastern Mediterranean basin: a reevaluation

The origin of the Eastern Mediterranean basin (EMB) by rifting along its passive margins is reevaluated. Evidence from these margins shows that this basin formed before the Middle Jurassic; where the older history is known, formation by Triassic or even Permian rifting is indicated. Off Sicily, a deep Permian basin is recorded. In Mesozoic times, Adria was located next to the EMB and moved laterally along their common boundary, but there is no clear record of rifting or significant convergence. Farther east, the Tauride block, a fragment of Africa–Arabia, separated from this continent in the Triassic. After that the Tauride block and Adria were separate units that drifted independently. The EMB originated before Pangaea disintegrated. Two scenarios are thus possible. If the configuration of Pangaea remained the same throughout its life span until the opening of the central Atlantic Ocean (configuration A), then much of the EMB is best explained as a result of separation of Adria from Africa in the Permian, but this basin was modified by later rifting. The Levant margin formed when the Tauride block was detached, but space limitations require this block to have also extended farther east. Alternatively, the original configuration (A2) of Pangaea may have changed by ∼500 km of left-lateral slip along the Africa–North America boundary. This implies that Adria was not located next to Africa, and most of the EMB formed by separation of the Tauride block from Africa. Adria was placed next to the EMB during the transition from the Pangaea A2 to the Pangaea A configuration in the Triassic. Both scenarios raise some problems, but these are more severe for the first one. Better constraints on the history of Pangaea are thus required to decipher the formation of the Eastern Mediterranean basin.

Neotethyan ophiolitic rocks of the Anatolides of NW Turkey and comparison with Tauride ophiolites

The I2zmir–Ankara–Erzincan zone in Turkey is part of the Anatolide belt. In NW Anatolia, near Kütahya, the ophiolitic rocks within the I2zmir–Ankara–Erzincan suture zone have a tholeiitic character and oceanic back-arc chemistry. Amphibolites form a metamorphic sole to part of the ophiolite in the Kütahya region and yield an 40 Ar/ 39 Ar age of 93 ± 2 Ma, interpreted to record high-grade metamorphism and intra-oceanic thrusting of pre-existing ocean crust. Gabbros and dykes yield 40 Ar/ 39 Ar ages of 94 ± 13 Ma and 48 ± 12 Ma. The first is suggested to be the ophiolite formation age, and the second a regional metamorphic event. The ophiolitic rocks of the Kütahya region are composite and record several events in the evolution of a Neotethyan seaway situated in north–central Anatolia and farther east. They are interpreted to have formed in a small ocean basin marginal to the subducting I2zmir–Ankara–Erzincan ocean. The Kütahya ophiolites of the Anatolide belt are similar in age to the Tauride ophiolites, and the sub-ophiolite metamorphic rocks and dykes in the ultramafic parts of the ophiolites in the Anatolide–Tauride Block formed at the same intraoceanic subduction zone within the same Neotethyan ocean.

Stratigraphical evidence for the depression of the northern margin of the Menderes–Tauride Block (Turkey) during the Late Cretaceous

Upper Cretaceous units on the Menderes–Tauride Block show a transition from a passive continental margin to a pelagic basin. This transition is related to the emplacement of ophiolitic nappes. The pelagic sediments were studied in the Aydıncık and Arslanköy (Mersin) areas in the central Tauride region, and in the Munzur Mountains in eastern Tauride region. In the Aydıncık area Upper Cretaceous units consist of Upper Campanian carbonate breccias with rudist fragments; Upper Campanian–Lower Maastrichtian slope-to-basinal sediments overlie these carbonate breccias disconformably. In the Arslanköy area the Upper Campanian–Maastrichtian Yavca Formation consists of Globotruncana-bearing biomicrites, siliciclastic turbidites, calciturbidites and debris flows and overlies Jurassic–Cretaceous platform carbonates disconformably. The uppermost levels of the Liassic–Cenomanian platform carbonates in the Munzur Mountains are composed of Cenomanian Hippurites/Orbitolina-bearing reefal limestones and then Turonian–Campanian Globotruncanidae-bearing biomicrites.The stratigraphic sequence in the Menderes–Tauride Block shows that rifting to form a northern Neotethyan basin took place in the Triassic and gave rise to the Inner Tauride Ocean. From Jurassic to Cenomanian times, the northern part of the Menderes–Tauride Platform formed a passive continental margin. In the Late Cretaceous the Inner Tauride Ocean is believed to have commenced intra-oceanic, northward subduction. Inner Tauride oceanic crust-derived nappes were emplaced southward onto the Menderes–Tauride Block. Flexural foreland basins in which pelagic sediments were deposited were formed in the Taurus Mountains related to southward thrusting and the emplacement of the ophiolite nappes.

Kinematic evidence for Late Mesozoic–Miocene emplacement of the Lycian Allochthon over the Western Anatolide Belt, SW Turkey

AbstractRecent controversies relating to the transport directions of the Lycian Allochthon and the kinematic relationships of this to the underlying Menderes Massif are addressed by looking at the structural record preserved at the main tectonic boundaries within the Lycian Allochthon. Rocks today within the Lycian Thrust Sheets were deposited as a north‐facing Late Palaeozoic– Mesozoic rift/passive margin succession that formed in a northern Neotethys Ocean separating the Menderes–Tauride block and Eurasia. The allochthon was emplaced onto the southern continental margin in stages from latest Cretaceous to Late Miocene times. Throughout the Lycian Allochthon early kinematic fabrics indicate that the allochthon was emplaced, and successively transported, from northwest to southeast. Mylonites at the contact between the Lycian Allochthon and the underlying Menderes Massif exhibit top‐to‐the‐east non‐coaxial flow. The major tectonic boundaries within the allochthon preserve various kinematic indicators showing top‐to‐the‐southeast transport.An intra‐platform basin (Tavas/Bozdağ unit), represented by structurally low Mesozoic–Palaeogene successions, probably originated as a rift basin between the Menderes Massif to the north and the Bey Dağları carbonate platform to the south. However, there is no structural evidence that the Lycian Thrust Sheets or the Lycian Peridotite Thrust Sheet were rooted in this basin. Copyright © 2003 John Wiley & Sons, Ltd.

Constrains on the origin and history of the Eastern Mediterranean basin

The basin formed along the northern passive margin of Gondwanaland as a relict of the Mesozoic Neotethys in early Mesozoic time. Though direct information from the basin itself is meagre, the geology of its passive margins and the regional framework of the Tethys evolution constrain the formation and history of the basin. The Eastern Mediterranean and its passive margins are interpreted to have formed as a result of several faulting and continental breakup phases from Early Permian to Middle Jurassic times, before Pangaea's complete disintegration. This led to the detachment of the Eratosthenes and Tauride blocks from the margins of the Levant and Herodotus basins, respectively. The latter merged in the northeast with the Cyprus basin that extended along Arabia's northern margin. The main rifting probably occurred in the Triassic, leading to seafloor spreading in the Herodotus and Cyprus basins, while along the Levant margin important rifting also occurred in the Jurassic. During the initial rifting stages extension perpendicular to the Levant margin was important, but subsequently the Tauride block drifted mainly northward. The existence of the passive margins and slopes of the Eastern Mediterranean is documented at least from the end of the Middle Jurassic. Until then the basin was probably narrow (≤200–300 km?), but during the main phase of the Africa–Laurasia separation it grew to twice its present width, or more. This scenario depends critically on the interpretation that the Tauride block was originally located next to northeastern Africa on the western side of the Eratosthenes block. Plate convergence and consumption of the northern portion of the basin have taken place since mid-Cretaceous times, but the active convergent boundary on its northern side formed only in the Neogene by modification of earlier structures. Some intra-plate deformation also took place, especially in the Neogene, but it hardly changed the original configuration of the remaining portion of the basin.

Permian-early Mesozoic tectonism and continental margin formation in Israel and its implications for the history of the Eastern Mediterranean

Summary The Early Mesozoic tectonic reorganization of the Tethys region also affected the Levant area. Here two processes were superimposed: (a) The pattern of long-wavelength vertical motions of the Arabo-Nubian platform changed in the Late Permian when Israel and nearby areas began to subside. (b) Rifting occurred in this subsiding area, probably in several phases: Late Anisian (and Ladinian?), Carnian-Norian, and Liassic. Differential movements reached 2–3 km and magmatism occurred in the Liassic and perhaps also in the Triassic. The tectonism was strongly felt up to 50 km landward of the present coast. The crust was thinned and modified under the present continental margin and in the main rifts. Passive margin conditions were established in Late Liassic times over the previously faulted area. Later in the Jurassic a carbonate shelf was constructed along this subsiding margin; its basinward edge was 1–1.5 km high, which shows that the adjacent SE Mediterranean was already a deep sea. Hence this basin and its passive margin are considered to have been shaped by the Early Mesozoic rifting which is recognized in Israel. The rifting process probably signifies oblique separation of the Tauride block from the Levant part of Gondwana.