FISSION-TRACK DATING AND THERMAL HISTORY OF SOME VOLCANIC AND PLUTONIC COMPLEX ROCKS FROM TURKEY AND FRANCE

Two sets of natural samples of known ages and different geological his tory have been investigated using the fission track dating method. The corresponding thermal history is studied by extracting: (1) apatite f rom three lavas samples belonging to the Tertiary Bodrum volcanic comp lex in Turkey; (2) apatite and sphene were extracted in a single sampl e of an hercynian granite from the Vosges massif in France. In both ca ses, these rocks had already been dated either by the K/Ar conventiona l method or by the Ar-40/Ar-39 method on biotite, K-feldspars or amphi bole. For this work, from analysis of both the track length distributi ons and fission track ages the thermal history can be retraced. For th e Turkish samples, the apatite fission track ages are interpreted as e mplacement ages. On the other side, for the French sample, the apatite and sphene fission track analysis show a moderate reheating episode a fter the lower Triassic.