Four glaciation phases have been reconstructed on the basis of glacial scouring. The oldest (Phase 1) is characterized by south-moving ice streams from the Jostedal glacier Plateau and Jotunheimen. Southwesterly movements during Phase 2 are attributed to an ice divide located further east, probably from
Weichsel maximum. The regional ice movements towards the SE during Phase 3 suggest ice flow from the Jostedal Plateau, probably of late Younger Dry as - Early Preboreal age. At the actual deglaciation, small, local ice caps existed in the mountains (Phase 4).
On the basis of lateral moraines and other marginal deposits, two preboreal events, the Årøya - Solvorn Event and the Hafslo Event, are reconstructed.
These events show glacial stagnations and advances, probably due in part to climate deteriorations, during the Preboreal deglaciation. The Årøya - Solvorn Event is assumed to be somewhat older than the Gaupne Stadial in the neighbouring area. The drainage history of the Hafslo basin is reconstructed.