THE TECTONOSTRATIGRAPHY OF CYCLADIC BLUESCHIST UNIT ON SIKINOS AND SIFNOS: IMPLICATION FOR THE MESOZOIC TECTONIC SETTING

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Published: Jul 27, 2016
DOI: https://doi.org/10.12681/bgsg.11707
Keywords:
Ductile thrust Incipient Ocean Hellenides
S. Papadopoulou
University of Patras, Department of Geology
E. Aravadinou
University of Patras, Department of Geology
C. Karavoulia
University of Patras, Department of Geology
P. Xypolias
University of Patras, Department of Geology
Abstract

This study presents new results for the tectonostratigraphic configuration of the Cycladic Blueschist unit (CBU) in the islands of Sikinos and Sifnos. These results show that the observed tectonostratigraphy in CBU results from tectonic repetitions of a thinner sequence. Tectonic repetitions have been achieved by a series of largescale ductile thrusts that operated during burial and exhumation of CBU. Restoration of the tectonostratigraphy in both islands implies an original, pre-metamorphic sequence, which was made up by a volcano sedimentary complex at the base and an overlying carbonate-rich sedimentary succession. This Mesozoic protolithic sequence was possibly formed in a continental terrane or in a transitional domain between a continental terrane and an oceanic basin. We suggest that the Mesozoic protolith of the CBU was formed in an incipient oceanic basin rather than a mature ocean like Pindos Ocean. This incipient oceanic basin was developed either along south part or along the north margin of Pelagonian microcontinent.

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  • Structural Geology
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