Paleontología y condiciones de depositación del Mioceno marino en las nacientes del río Futa, Valdivia, Chile

Abstract

Fossil samples collected near the Futa river sources, 33 km south southwest from Valdivia (Chile), bearing remains of bryozoans, brachiopods, bivalves, gastropods, worms, cirripeds and echinoids, besides of trace fossils, leaves and forams are estudied. Struthiolarella chilensis (Philippi, 1887) is remarkable among the mollusks as a predominant species, with an Early to Middle Miocene age. Recent studies on forams, in the same area, allows to restrict the age of the sequence at Futa river to the Middle Miocene. Almost the whole taxa in the fossiliferous assemblages have not been recorded previously and they are considered new for the region. The occurrence of oysters, barnacles and well preserved prints of fossil leaves, would indicate the existence of positive areas close to the place of initial deposition; this elements were removed to deeper environments to compose the final thanatocenosis. Figures and comments about Ihe most significant fossils are also given.