DEPOSITIONAL CONDITIONS OF PLEISTOCENE ALLUVIAL FAN DEPOSITES IN THE GÜZELYURT BASIN (TURKISH REPUBLIC OF THE NORTHERN CYPRUS)

Yıl 1995, Cilt: 117 Sayı: 117, 40 - 41, 01.10.1995

Engin Olgun

Öz

The alluvial fan deposites are
widely distributed in the Güzelyurt basin. In the southern pan of the Güzelyurt
basin, these deposites unconformably overlie the units of Middle-Late
Cretaceous Troodos massive, Late Miocene-Early Pliocene Myrtou Marls and Late
Pliocene Athalassa formation. Towards the north, they are unconformably
overlain by recent alluvium deposits. The fan deposites are deposited by
high-viscosity debris flows and braided streams dominated by sheet-flood
events. Six different lithofacies are recognized; (A) Clast supported
conglomerates are hyper-concentrated debris flow deposits, (B) Matrix supported
conglomerates represent mud flow deposits, (C) Thick bedded sandy conglomerates
represent sheet-flood and braided-stream deposits, (D) Clast supported, thick
bedded conglomerates with interbedded sandstones are suggested as a
braided-stream deposits, (E) Thirs bedded sandstones and conglomerates
represent sheet-flood deposits by very shallow migrating channels on a broad,
planar surface during upper-flow regime, (F) Caliche bearing mudstones
represent distal sheet-flood deposits in semiarid dimates At the end of the
Late Pliocene, due to the rapidly uplifting of the Troodos massive, the
coarse-very coarse pebbles of alluvial sediments are deposited as the inner fan
deposites over the Pliocene sediments. As from Middle Pleistocene, the other
alluvial fan fades are deposited together with relatively the coarse facies.
The depositional conditions and the caliche concentrations in the alluvial fan
deposites indicate a semi-arid climate.

Anahtar Kelimeler

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Kaynakça

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