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Six individual tectonostratigraphic units are identified within the Izmir-Ankara-Erzincan Suture Zone in the critical Erzincan area of the Eastern Pontides. The Aylkayasl Formation of Campanian-Maastrichtian age is composed of bedded pelagic limestones intercalated with polymict, massive conglomerates. The Ayikayasi Formation conformably overlies the Tauride passive margin sequence in the Munzur Mountains to the south and is interpreted as an underfilled foredeep basin. The Refahiye Complex, of possible Late Cretaceous age, is a partial ophiolite composed of ~ 75% (by volume) serpentinized peridotite (mainly harzburgite), ~ 20 % diahase and minor amounts of gabbro and plagiogranite. The complex is interpreted as oceanic lithosphere that formed by spreading above a subduction zone. Unusual screens of metamorphic rocks (e.g. marble and schist) locally occur between sheeted diabase dykes. The Upper Cretaceous Karayaprak Melange exhibits two lithological associations: (1) the basalt + radiolarite + serpentinite association, including depleted arc-type basalts; (2) the massive neritic limestone + lava + volcaniclastic association that includes fractionated, intermediate-composition lavas, and is interpreted as accreted Neotethyan seamount(s). The several-kilometre-thick Karadag Formation, of Campanian-Maastrichtian age, is composed of greenschist-facies volcanogenic rocks of mainly basaltic to andesitic composition, and is interpreted as an emplaced Upper Cretaceous volcanic arc. The Campanian-Early Eocene Sutpinar Formation (~ 1500 m thick) is a coarsening-upward succession of turbiditic calcarenite, sandstone, laminated mudrock, volcaniclastie sedimentary rocks that includes rare andesitie lava, and is interpreted as a regressive forearc basin. The Late Paleocene-Eocene Sipikor Formation is a laterally varied succession of shallow-marine carbonate and siliciclastic lithofacies that overlies deformed Upper Cretaceous units with an angular unconformity. Structural study indicates that the assembled accretionary prism, supra-subduction zone-type oceanic lithosphere and volcanic are units were emplaced northwards onto the Eurasian margin and also southwards onto the Tauride (Gondwana-related) margin during Campanian-Maastrichtian time. Further, mainly southward thrusting took place during the Eocene in this area, related to final closure of Tethys. Our preferred tectonic model involves northward subduction, suprasubduction zone ophiolite genesis and arc magmatism near the northerly, Eurasian margin of the Mesozoic Tethys. Keywords: Tethys, Pontides, stratigraphy, suture zone, Turkey.

Structural data and a regional tectonic interpretation are given for the NE-SW-trending Hatay Graben, southern Turkey, within the collision zone of the African (Arabian) and Eurasian (Anatolian) plates. Regional GPS and seismicity data are used to shed light on the recent tectonic development of the Hatay Graben. Faults within Upper Cretaceous to Quaternary sediments are categorized as of first-, second- and third-order type, depending on their scale, location and character. Normal, oblique and strike-slip faults predominate throughout the area. The flanks of the graben are dominated by normal faults, mainly striking parallel to the graben, that is, 045-225[degrees]. In contrast, the graben axis exhibits strike-slip faults, trending 100-200[degrees], together with normal faults striking 040- 060[degrees] and 150-190[degrees] (a subset strikes 110-130[degrees]). Similarly orientated normal faults occur throughout Upper Cretaceous to Pliocene sediments, whereas strike-slip faults are mostly within Pliocene sediments near the graben axis. Stress inversion of slickenline data from mostly Pliocene sediments at ten suitable locations (all near the graben axis) show that [[sigma].sub.3] directions (minimum stress axis [approximately equal to] extension direction) are uniform in the northeast of the graben but orientated at a high angle to the graben margins. More variable [[sigma].sub.3] directions in the southwest may reflect local block rotations. During Miocene times, the Arabian and Anatolian plates collided, forming a foreland basin associated with flexurally controlled normal faulting. During the Late Miocene there was a transition from extension to transtension (oblique extension). The neotectonic Hatay Graben formed during the Plio-Quaternary in a transtensional setting. In the light of modern and ancient comparisons, it is suggested that contemporaneous strain was compartmentalized into large-scale normal faults on the graben margins and mainly small-scale strike-slip faults near the graben axis. Overall, the graben reflects Plio-Quaternary westward tectonic escape from a collision zone towards the east to a pre- or syn-collisional zone to the west in the Mediterranean Sea. Keywords: strike-slip faults, normal faults, Dead Sea Fault, East Anatolian Fault, Eastern Mediterranean, strain analysis, neotectonics.

Field evidence from north-south transects tests three tectonic models for Tethys in Western Turkey for when a Late Palaeozoic ocean was closing and an Early Mesozoic ocean opening. In Model 1, a Palaeozoic ocean subducted southwards, rifting continental fragments from Gondwana and opening a Triassic Neo-Tethys to the south. Closure and collision occurred by latest Triassic time. In Model 2, a wide Palaeozoic Tethys subducted northwards with an active Eurasian margin and a passive Gondwana margin. The northern Gondwana margin rifled in the Triassic; fragments either remained nearby (Taurides) or drifted northwards (e.g. Karakaya) attached to a north-subducting plate. New oceanic crust replaced Palaeo-Tethys with Neotethys and back-arc marginal basins opened along the south Eurasian margin (e.g. Kure). In Model 3, a Palaeozoic ocean also subducted northwards opening wide marginal basins. A wide Southern Neotethys opened along the Gondwana margin. Rifted Eurasian (Anatolides) and Gondwana (Taurides) fragments collided in mid-Tethys by latest Triassic time. Field evidence from the Pontides supports north-dipping subduction models (Model 2 or 3 above). Key features are a south-vergent, HP--LT accretionary prism, magmatic arc and back-arc basin system bordering the Eurasian margin. Also, evidence from the Tauride Mountains favours Model 2 over Model 3. Critically, the Anatolides and Taurides appear to have a common history and were unlikely to have been located on opposite sides of Tethys, as in Model 3. Keywords: Western Turkey, Tethys, Triassic, subduction.

The Beysehir-Hoyran-Hadim Nappes crop out over 700 km from NW to SE. Above a regionally autochthonous Tauride carbonate platform the Beysehir-Hoyran Nappes begin with a thrust sheet (c. 400 m) of mainly redeposited carbonates, quartzose sandstones and mudstones of Mid-Late Triassic age, interpreted as a proximal slope-base-of-slope succession. Above is a thrust sheet (c. 1 km) of Middle-Upper Triassic intermediate-acidic extrusive rocks, volcaniclastic rocks and minor pelagic carbonates, interpreted as a continental rift. Thin ( Keywords: Turkey, Neotethys, tectonics, thrust sheets, orogeny.

The Lycian Taurides of SW Turkey consist of an allochthonous Mesozoic passive margin succession that was episodically detached from its autochthon and translated southeastwards between latest Cretaceous to Late Miocene times. A combination of structural analysis, sedimentology, palaeontology and geochemistry allows subdivision of this orogenic event into: (1) latest Cretaceous trench-passive margin collision causing ophiolite obduction and detachment of the Koycegiz Thrust Sheet; (2) Mid-Late Eocene continent-continent collision renewing southeastwards thrusting and causing detachment of the Teke Dere Thrust Sheet and Yavus Thrust Sheets; (3) Miocene extensional collapse of the orogen with southeastwards translation of the allochthon coeval with rift-basin formation in the hinterland. Keywords: Turkey, Lycian Taurus, thrust sheets, extension, orogeny.

The Aksu Basin, within the Isparta Angle area of SW Turkey, documents Plio-Pleistocene crustal processes at the interface between the Tauride Mountains and the Eastern Mediterranean Sea. Basin sedimentation began in the Late Miocene, following an earlier history of emplacement of Mesozoic allochthonous units (Antalya Complex), Miocene basin development and localized Late Miocene compression (Aksu Phase). Late Miocene Early Pliocene transtension deformed the Aksu Basin, exploiting pre-existing zones of structural weakness. During Early-Mid-Pliocene, muddy sediments accumulated in a shallow shelf sea ( Keywords: Turkey, Pleistocene, Pliocene, tectonics, sediments.

The Lycian thrust belt is an important part of the Tethyan orogenic belt in the eastern Mediterranean region. It includes a unit of internally disrupted, thin-skinned thrust sheets (layered tectonic melange) and a melange rich in ophiolitic material (ophiolitic melange). The layered tectonic melange is dominated by Mesozoic distal deep-water sedimentary rocks, and the ophiolitic melange includes disrupted thrust sheets of early Mesozoic shallow-water limestone and blocks of basalt of both mid-ocean ridge and within-plate geochemical affinities. A complete record of closure of a Tethyan oceanic basin began with Late Cretaceous intraoceanic subduction, followed by latest Cretaceous trench-continental collision, and ended with mid-Tertiary continental collision, and orogenic collapse.

Several pre-Jurassic tectonic units in NW Turkey are crucial to the current debate regarding the timing and direction of subduction of Palaeotethys, a major ocean that separated Eurasia and Gondwana in Late Palaeozoic-Early Mesozoic times. The most critical unit is the Karakaya Complex, a deformed, low-grade assemblage of oceanic origin which comprises a NW-verging, SE-dipping stack of tectonostratigraphic units, here interpreted as a Palaeotethyan accretionary complex. The units display lithologies consistent with origins in seamount, trench, abyssal and rifted carbonate platform settings. Clastic basin sequences developed on top of the complex. Other relevant tectonostratigraphic units in the area include ultrabasic rocks of supra-subduction zone affinity, which tectonically overlie Permian carbonate platform units with intervening metamorphic soles and melanges. Restored structural trends suggest the presence of a southward-dipping Palaeotethyan subduction zone bordering Gondwana-related units during the Late Permian-Triassic. This was probably additional to more important regional northward subduction along the southern margin of Eurasia from the Eastern Mediterranean to the Himalayas. Keywords: Turkey, Tethys, subduction, accretion, ophiolites.

Well-preserved Radiolaria have been discovered in calcareous silt turbidites and mudstones intercalated with basic extrusives of the Guevgueli Ophiolite, northern Greece. The mudstones contain terrigenous silt, probably derived from adjacent continental basement of the Serbo-Macedonian and/or Paikon units. Volcanic quartz and rare volcanic glass were probably derived from an active continental margin arc (Paikon volcanic arc) to the west. The radiolarian sediments were deposited within fault-controlled hollows in the ophiolitic extrusives, and then covered by massive and pillowed extrusives. The radiolarian assemblage is indicative of an early Late Jurassic (Oxfordian) age, which therefore dates the genesis of the Guevgueli Ophiolite. Our data are consistent with the age of the intrusive Late Jurassic Fanos Granite, believed to be contemporaneous with the Guevgueli Ophiolite. In general, the Guevgueli and related ophiolites of northern Greece are thought to have formed within a transtensional intra-continental marginal basin, generated in response to oblique eastward subduction of older Tethyan oceanic crust (Almopias ocean).

In an attempt to cnstrain the timing and mode of tectonic uplift of the classic Troodos ophiolite, colonial corals were collected from Quaternary littoral raised terraces in coastal southern Cyprus and dated using the uranium-series disequilibrium method. A total of 28 samples of Cladocora caespitosa were collected at five localities from the 8-11-m-high and