TThe Troodos Ophiolite was formed in a Supra Subduction Zone. Its subsequent uplift and the emergence of the island of Cyprus is directly connected with the subduction and collision of the African Continental plate with the Eurasian Continental plate. This collision resulted in:
a) The cessation of subduction,
b) The detachment of the Troodos Ophiolite block and its subsequent 90o counterclockwise rotation,
c) The obduction of the Mamonia Complex on the borders of the Troodos geotectonic zone and their amalgamation.
The continuous northward movement of the African plate resulted in the amalgamation of the Troodos-Mamonia zone with the Kyrenia Range. Due to tectonic quiescence southward of this collision zone, sediments were deposited in deep-sea environments that progressively shallowed, with the Troodos Mountain emerging from the sea in Miocene time.
A second major tectonic event at the end of the Miocene affected the northern part of Cyprus, as it is present today. A series of allochthonous carbonates were thrust southward on the northern hillsides of Troodos, thus folding and thrusting the younger sediments. At that time east of Cyprus the Neotethys Ocean closed up and the Mediterranean Sea almost acquired its current configuration.
However, the African Continental plate continued its northward propagation, culminating in a change in the relative movement of the plates in order to achieve a new balance. A new subduction zone developed south and south-west of Cyprus, while in the east a strike-slip zone prevails. The continuous movement of the African and Arabian Continental plates towards the north, and more specifically the collision of the Arabian plate with the Anatolian Microplate (position of Turkey today), resulted in the westward escape of the Anatolian Microplate along two major strike-slip faults (North Anatolian and East Anatolian faults).
At the end of the Miocene, a fragment of continental crust known as the Eratosthenes Seamount was “separated’’ from the African Continental plate (~200 million years ago) and reached the subduction zone. This continental crust is lighter and contained a larger volume of water compared to the oceanic crust of the Troodos Ophiolite. As the continental crust subducted under the Troodos Ophiolite, it exhumed large volumes of water which migrated upwards and became the driving force behind the serpentinization of the ultramafic ophiolite and the mantle sequence rocks. The serpentinite rocks rose due to their lighter relative density and thus aided in uplifting Troodos. This uplift was also aided by the buoyancy of the subducting continental crust, which was uplifting the oceanic crust gradually. The rate of uplift was probably changing as it is observed by high erosional surfaces and the deep, steep valleys created by rivers during episodes of strong uplift. Large quantities of erosional material were transported and deposited forming the Pleistocene Fanglomerate formation and the marine terraces around the island, which attest to the gradual uplift of the island of Cyprus.
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