The high altitude Alpine arc is characterised by the existence of numerous underground level carstic phenomenon, with the presence of caves, underground passages and a hydrographic network developed inside the mountain. The carstic nature of the territory can also be seen on the surface, testified by cavities of different shapes and dimensions. We can find deep wells at high altitude like those ones generated by white malm limestone or more superficial like the lapiaz wells corresponding with junctions or fault lines. Some cavities are the result of underground phenomenon getting in contact with the surface: it is the case of the Labassa cave in the Gorge of the Chiesetta and the entry of the Arma delle Mastrelle. More other typical carstic morphologies are the dolines, closed depressions which on the territory of the Park present less deep troughs, with a smaller diameter than ten metres, the carstic clefts frequent above all in the Carsene Basin and morphologies of fewer dimensions generated by corrosion like the grooved fields, the carstic holes and the small corrosion basins.

All this phenomenon have been generated by the particular Marguareis rocky configuration: the different types of carbonate rocks where it is composed of, by the Jurassic limestone to the Cretaceous ones, have initiated a unique panorama in continuous evolution.