First age dating of the Lydian stones in the Inner Hellenides (Mount Parnis, Greece); geological significances.

Using radiolarian and conodont remains, a Tournaisian age has been obtained from the Lydian rocks (or lydites) of the Parnis Mount (Greece); this resu lt is the first direct age dating of the Lydian rocks of continental Greece . In the same area, some limestone strata, interbedded in sandstones, yield Carboniferous and Permian foraminifers; the established stratigraphy is no t consistent and so, the Lydian rocks have to be considered as blocks in an olistostrome unconformably overlain or thrusted by Triassic limestones. Ot herwise, the Lydian rocks are interpreted as biogenic siliceous deposits du e to the absence of carbonate sedimentation (not as a high siliceous produc tion). (C) 2000 Academie des sciences / Editions scientifiques et medicales Elsevier SAS.