The Geology of Cyprus
By Christos Constantinou*, BSc, MSc
The most important fact in the geological evolution of the island of Cyprus is the ophiolite complex of Troodos. After dating analysis, the estimated age of the ophiolite of Troodos is set in the Upper Cretaceous era. The main reason for the formation of the ophiolite is attributed to the changes on the lithospheric plates of the area of Cyprus.
The Troodos Mountain, which appears at the back of the picture, is also Cyprus’ highest mountain.
Four major tectonics events which shaped the geological history of Troodos:
• The first one was the ‘birth’ of the ophiolite complex;
• The anticlockwise rotation of this complex;
• The Keryneia overthrust, and
• The deposition of continental crust below Troodos mountain
The tectonic evolution of Cyprus (Fig1 (a), (b), (c)). N and S to refer to the present North and South. Sub-figure ‘d’ shows the rotation that took place of the cover by 90° anticlockwise rotation (Clube and Robertson, 1986).
Geomorphological Sections of Cyprus
Cyprus rock formations can be separated into four (4) geomorphological sections, namely:
• Troodos mountain range
• Pentadaktilos mountain range
• Mesaoria plain
• Coastal areas
Schematic model of the tectonic evolution of the Eastern Mediterranean sea from the Mesozoic era until today. AFRB represents the African Basement. AFR represents Africa after the Arabia Plate separated from the African Plate. ANA represents the Anatolian Plate (Kempler, 1998).
The Troodos mountain range has a maximum height of 1951 metres above the sea level. The mountain top is called Olympos. Also there are other mountains tops like Madari (1612m), Papoutsa (1554m), Kykkos (1407m). The total area of Troodos range is about 3200km2 and it consists of ophiolitic rocks which are the most well-developed and better known ophiolite complex in the world. In the south part of Troodos, the fossilized fault of Arakapas is encountered which in its most part is inactive and has a direction East-West.
The unity of Pentadaktylos mountain range extends along the coastal zone in the north of Cyprus and it constitutes a physical barrier to entry of the sea in the mainland. It has a width of about 13km and the total length of the area is 160km. It extends from Cape Apostolos Andreas (Northeast) to Cape Kormakitis (West). The altitude of the mountain ranges between 700 and 1024 meters and consists mainly of limestone. The mountainous section of Kyrenia is approximately 90km long with a width of about 3km and an altitude ranging from 200 meters to 1024 meters as opposed to the sub-mountainous section which has an altitude of 0 to 200 meters. Although not visible, the sub-mountainous part of the Pentadaktylos Mountain covers a much larger area than the above-terranean section.
The plain of Messaoria located on the intermediate vicinity between the mountains of Pentadaktylos and Troodos Mountains. This plain covers an area of approximately 88 km, from the Bay of Morphou up to the bay of Famagusta, and its width is approximately 20 km. A sizable part of the plain of Messaoria is located at an altitude of 150 meters. Even after the emergence of the Troodos and Pentadaktylos Mountains, the region remained below the sea level until recent geological times.
Map of Cyprus showing the Troodos ophiolite, the Mamonia complex and the Keryneia sequence (Robertson & Xenophontos, 1993).
The coastal zone of Cyprus consists mainly of a smooth coastline of a small width. In several places there are sandy bays such as those of Famagusta and Morphou.
Litho-Stromatography of Cyprus
The litho-stromatographic sections of Cyprus comprise the:
• Troodos sedimentary sequence which consists of sediments dating from the Upper Cretaceous (Campanian–Maastrichtian) to Holocene. The constituent sediments that make-up the Troodos range are bentonite clays, Chalks, marls, sandstones and calcite sandstones, Gravels, sands and silts, Calcitic sandstones, sands and gravels, Sands, silts, clays and gravels.
• Troodos ophiolite – axial sequence, is divided into five sections, which form the roof downwards. These are: Perapedi formation (umber), volcanic rocks (pillow lavas), reef rocks, plutonic rocks (plagiogranites, gabbro, pyroxenites, verlite, dunite) and mantle sequence (serpentinite, harzburgite).
• Arakapas sequence – Transform fault: consists of breccia lavas, Lavas and volcanoclastic rocks, Penetrations of plutonic rocks and fragmented serpentinite.
• Keryneia sequence is a sequence made-up of the oldest rocks in Cyprus. The sequence of Kyrenia has longitudinal development of Cape Apostolos Andreas to Cape Kormakitis. This sequence is characterised by the northernmost mountain range in Cyprus: Pentadaktylos which has an altitude of 1024 meters. This area is considered the southernmost occurrence of the Tavro-Dinaric Alpine Zone. In the north the mountain range is separated by a wide valley and up to five kilometres to the south lies the plain of Messaoria. The sequence of Kyrenia consists of autochthonous and allochthonous sequences. The native sequence includes formations Kithraia, Kalograia–Ardanon and Lapithou while the allochthonous sequence comprises formations Agios Hilarion, Sigxari Dhikomo and Kantara. The ages of these formations range from Carboniferous–Permian (massive limestones) to Neogene–Middle Miocene.
• Mamonia complex in SW Cyprus consists of sedimentary and volcanic rocks of Middle Triassic age to Upper Cretaceous age. These deep-sea sediments and volcanic rocks represent remains of a passive continental margin and oceanic crust which formed in a small Mesozoic oceanic basin Neotythyos (Robertson and Woodcock, 1979).
Geological map of Cyprus showing the island’s major tectonic elements (Morris et. al. 1998).
References:
Clube, T., & Robertson, A.H.F. 1986. The Palaiorotation of the Troodos microplate, Cyprus, in the Late Mesozoic – Early Cenozoic plate tectonic frame – work of the Eastern Mediterranean. Surveys in Geophysics, 8, 375-434.
Kempler, D. 1998. 53. Eratosthenes seamount:The possible spearhead of incient continental collision in the eastern Mediterranean. Proceedings of the Ocean Drilling Program, Scientific Results.
Robertson, A., Xenophontos, C. 1993. Development of concepts concerning the Troodos ophiolite and adjustment units in Cyprus. Geological Society, London, Special Publications 1993.
Robertson, A.H.F. & Woodcock, N.H. 1979. The Mamonia complex, southwest Cyprus: the evolution and emplacement of a Mesozoic continental margin. Geological Society of America.
Morris, A., Anderson, W.M., Robertson F.H.A. 1998. Multiple Tectonic rotations and transforms in an intraoceanic suture zone, SW Cyprus. Tectonophysics 299.
*Christos Konstantinou is Geologist
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