Geological Society of London
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Field relations, geochemistry and origin of the Upper Cretaceous volcaniclastic Kannaviou Formation in western Cyprus: evidence of a southerly Neotethyan volcanic arc

posted on 2016-06-21, 11:13 authored by Matthew F. Gilbert, Alastair H. F. Robertson

The Kannaviou Formation (up to 750 m thick) accumulated in a deep-sea setting in west Cyprus during Campanian–Early(?) Maastrichtian time. The formation depositionally overlies Upper Cretaceous ophiolitic lavas, including those associated with serpentinite-hosted arcuate lineaments. The Kannaviou Formation locally overlies ophiolitic serpentinite, indicating that mantle rocks were exposed on the seafloor prior to sediment deposition. Geochemical analyses of basalts that depositionally underlie the Kannaviou Formation, within the arcuate lineaments, indicate close similarities with the boninitic lavas of the South Troodos Transform Fault Zone in south Cyprus. Abundant volcanogenic and minor terrigenous and pelagic sedimentary rock material is present within the Kannaviou Formation, while kaolinite is common within interbedded red clays. Suitable terrigenous source lithologies are present in the deformed continental margin/deep-sea sedimentary rocks of the Mamonia Complex in west Cyprus. Whole-rock chemical analysis of sandstones of predominantly volcaniclastic origin indicates an intermediate arc-like composition. Electron microprobe analysis shows that glass is silicic, with a tholeiitic fractionation trend. Similar arc-like volcanic rocks of Late Cretaceous age are exposed in the western Kyrenia (Girne) Range, north Cyprus. The provenance of the Kannaviou Formation provides evidence of Late Cretaceous northwards subduction of the South Neotethys beneath a continental margin to the north.