E. Pereira et al., Castiglione (Oletta, Corsica): relationships between phenomena of calcification and tectonic fossiliferous fracture dating, GEODIN ACTA, 12(6), 1999, pp. 371-375
Six cavities have been discovered in the Oletta massif. The massif, today c
onstitued of Schistes lustres with several metres of calcareous layers abov
e them, has undergone intense fracturing. The networks of cavities are orga
nised along north-south and subequatorial directions, and form a narrow bay
onnet-network. All the elements in the galleries appear to be karstic: stal
agmites, stalactites and calcitic deposits along the walls; but no trace of
dissolution or excavation was found. Thus, the origin of the galleries is
only tectonic, while the calcitic deposits result from the dissolution of t
he old, thick calcareous layers above, which are no longer present. The thi
ckness and the volume of the calcitic deposits, which is variable depending
on the galleries, indicates the chronology of the different tectonic perio
ds which have fractured the massif. Five tectonic and successsive events ha
ve been detected. Calcitic datings confirm the timing of successional fract
uring, indicating also the variable age of the fossiliferous Middle Pleisto
cene deposits found in these cavities. (C) 1999 Editions scientifiques et m
edicales Elsevier SAS.