Agradecimentos: We are grateful to Professor Peter Hackspacher and to Daniel Godoy, from UNESP - Rio Claro, by the geological support concerning to this work and to State of São Paulo Research Foundation (FAPESP) which supported this work through a Doctoral Grant (E.A.C.C.), Process 02/13258-1, and a Thematic Project, Process 00/03960-5. We are also indebted to the unknown referee for valuable comments that improved our manuscript very much Ver menos

Abstract: Epidote fission-track dating (FTD) was performed through both Population and external detector method (EDM) in five samples from the Mantiqueira Mountain range, southwestern Brazil. The ages obtained via population conducted to a weighted mean age of (114 +/- 19) Ma. In order to perform EDM dating, it was necessary to measure the efficiency factor (g) between muscovite mica and epidote. Three measurements were performed and the weighted mean g value obtained was (0.57 +/- 0.03). The weighted EDM age was (98 +/- 7) Ma. The population error magnitude occurs due to the existence of few useful epidote grains. EDM provides dating with fewer grains, however there are difficulties concerning etching anisotropy that should be regarded. Both dating methods agreed Ver menos