The summit cap of Mont Ventoux is uniformly covered by a scree of lauzes, flat and fine stones used as tiles or slabs, due to the repeated action of frost and thaw, which shattered the limestone. It also tends to disintegrate under the action of intensive runoff of rainwater. Four active resurgences - the Font Martin, the resurgence of Notre-Dame des Anges, the Groseau, and the fountain of Vaucluse - located at the base of the massif are proof of its strong karstification.