Variations of water level in Vico Lake (Latium) related to climatic-environmental changes in Central Italy

Abstract

Morphological and stratigraphycal studies on the terraces and the sediments surrounding the Vico volcanic lake were carried out. The studies lead to the identification and to the dating of the remnants of Late Pleistocene and Holocene lacustrine terraces, lying higher than the current level. At present, the lacustrine level is regulated by the presence of a drainage tunnel that maintains the lake at an almost constant elevation, ca. 510 m. The lake had, in the course of its history, an intermittent outflow, fed only when the lake water exceeded the sill elevation. The lacustrine level reached 548-550 m during a period more recent than 28,720±1400 years BP, 538-540 m ca. 14,550±135 years BP.; ca. 11,000-10,000 years BP the level of the lake dropped to 510 m. The Vico lake level increases can be correlated to those of lake Fucino, in Abruzzo, having very different dimensions and catchement, and are also syncronous, in general terms, with the glacial advances in the Central Apennine. Therefore, the oscillations were caused by climatic variations that changed the hydrological budget in the lake Vico catchement. Two terraces, produced by holocene high stands, are also present; the first could be dated ca. 7000-6000 years BP, the second ca. 2800-2300 years BP according to the correlations with the lake Fucino water levels. A last terrace was probably formed after the XVI century hydraulics works.