The Campo Felice Plain, located at an altitude between 1524 and 1600 m, is in a closed basin of tectonic origin; its catchment consists of carbonatic rocks and includes mountains that exceed 2200 m in height. The greater portion of the sediments outcropping on the Plain are of glacial, alluvial and lacustrine origin, and can be dated to the Upper Pleistocene and Holocene. Older glacial and slope waste deposits could date back to the Middle Pleistocene. The detailed mapping of the glacial deposits and the evaluation of the equilibrium line altitude of the glaciers that produced them, allowed for the calculation of the temperature difference between the periods of glacial expansion and the present, which was accomplished through a comparison with the current theoretic equilibrium line altitude. The phases in which the lower limit of the discontinuous permafrost rose were recognised through the identification of inactive rock glaciers, that become more recent in age as their elevation rises. This limit can be considered indicative of the isotherm -1/-2°C of the annual average temperature. Using this value, it was possible to estimate the temperature difference in respect to the present. The study of the lacustrine sediments and the traces of the shore line placed in evidence lake Stillstands that can be dated to the period that spans from the Last Glacial Maximum to the Holocene. The examination of the nature of the karstic ponors showed that they had balanced the lacustrine levels and the karstic water table. The fluctuations of the lake level and the piezometric surface were produced by climatic-environmental variations. Only the development of the main ponor of the eastern zone of Campo Felice, in fact, produced the drainage of a large part of the lake located in that area. The formation of this ponor must be attributed to a substantial lowering of the karstic water table.

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