Biostratigraphy of the supra-ophiolite sediments of the Troodos Massif, Cyprus: the Cretaceous Perapedhi, Kannaviou, Moni and Kathikas formations

• Published in: Geological Magazine
• Main Authors: Urquhart, E., Banner, F. T.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 1994
• Subjects: Planktonic foraminifera
• Online Access: http://dx.doi.org/10.1017/s0016756800012127; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0016756800012127

Abstract The Troodos Massif of Cyprus exposes a classic and much-studied ophiolite sequence representing oceanic crust of Late Cretaceous age. K-Ar dating of the sheeted dykes and of the overlying pillow lavas gives a range of 83±3 Ma (earliest Campanian) and 75±5 Ma (late Campanian) respectively for the formation of the upper levels of the ophiolite. An autochthonous sequence of Late Cretaceous to Recent age sediments is exposed resting on the ophiolite, the oldest part of which reflects sedimentation in an apparently deep marine, oceanic setting. Little biostratigraphical information is available to constrain the chronostratigraphy of these sediments in relation to the complex geological history of the island, including the uplift and unroofing of the ophiolite, despite their richness in microfauna and flora. This paper provides an integrated biostratigraphical study based on radiolaria, planktonic foraminifera and calcareous nannofossils of the oldest part of the supra-ophiolite succession, of the Cretaceous Perapedhi, Kannaviou, Moni and Kathikas formations. For the first time, well-defined micropalaeontological evidence establishes the relative ages of these formations. The umbers of the Perapedhi formation are no younger than Campanian in age while the volcaniclastic sediments of the Kannaviou formation were also deposited during Campanian times. The matrix of the Moni formation contains a microfauna consistent with the hypothesis that it is derived from the Kannaviou. In contrast, the Kathikas formation is composed of sediment derived mainly from the allochthonous Mamonia complex, but autochthonous pelagic interbed horizons demonstrate that it was deposited probably within a very short time interval during the late Maastrichtian. Key index species are figured, including the first published micrographs of Cretaceous planktonic foraminifera from Cyprus.