Integrated stratigraphy and paleoceanographic evolution of the pre-evaporitic phase of the Messinian salinity crisis in the Eastern Mediterranean as recorded in the Tokhni section (Cyprus island)

.An integrated micropaleontologic, magnetostratigraphic and cyclostratigraphic investigation ofthe Tokhni composite section (Southern Cyprus Island, Eastern Mediterranean) refines the previously pub-lished age model and paleoenvironmental interpretation particularly concerning its uppermost pre-MessinianSalinity Crisis interval (pre-MSC), between 6.46 and 5.97 Ma. This section is characterized by a precession-paced alternation of red shales and limestones, which correlate with insolation maxima and minima on thebasis of their δ18O signatures and calcareous nannofossil assemblages. The planktonic foraminifer and mag-netostratigraphic events permit the tuning of the sedimentary cycles to the 65° N summer insolation curve andto the Mediterranean pre-evaporitic reference sections. The upper bathyal sedimentary succession of theTokhni composite section records paleoceanographic changes at 6.4 and 6.1 Ma, indicating increasinglystressed conditions both at the sea floor and in the water column. Compared to the Western Mediterraneanpre-MSC successions, we observe less severe sea floor anoxic conditions at times of insolation maxima andhigher salinity surface and bottom waters at times of insolation minima. Moreover, from 6.1 Ma to the MSConset we observe a progressively increase of continental-derived waters, which was likely caused by a tectonic pulse. The MSC onset at 5.97 Ma is marked by the deposition of clastic carbonates rather than primaryevaporitic facies and is approximated by the last recovery of foraminifera, the abundance peaks of Helico -sphaera carteriand Umbilicosphaera rotulaand the decrease of the 87/86Sr. The MSC onset is recorded twocycles below the Messinian erosional surface (MES, 5.60 Ma) and the overlying clastic evaporites, suggestinga hiatus of approximately 350 kyr.