Il Lacus Turni scomparso nella provincia di Roma

Abstract

The lakes known by the name of Lacus Turni or Lago di Turno, in the province of Rome, are two. The first, better known, is located near Pavona (Albano) and was also known in the past with the “Lago di Giuturna”, currently it is indicated with the name of the lake and was reclaimed by Paolo V in 1611; the second is located on the border between the territory of Rome and that of Pomezia, in the Macchia della Capocotta area, and today it is also completely extinct. The first lake develops in the upper Pleistocene after the phase of volcanic activity that determined the depression that hosts it, is well documented from the historical point of view and finds its precise geomorphological connotation. The second lake must have had a recent origin, probably from the seventeenth century, imposed on the deposits of the middle Pleistocene pp of the "ancient red dune" Auct., On one of the marine terraces bordering the Roman coast and was supposed to be food from some sub lake springs so as to originate an emissary that flowed towards the coast near Torvaianica. This lake, poorly documented from a historical point of view, disappears from the cartography around 1850 and its memory was completely lost. Its sub-circular shape, the modalities of its origin, the structural and stratigraphic context as well as the presence in the area of significant gaseous emissions both cold and hot, made it believe that its origin could be compatible with sinkhole similarly to what happened for numerous other small lakes and sinkhole ponds in the Lazio area