Tufite (5) Raw Minerals Stones Rocks Collecting

Description

Origin : Italy (Veneto)

Geological era : Middle Triassic (Ladinic)

Age : 242 million of years

Tufite Dolomitic Limestone 300-400 gr - cm 10-14 Raw Minerals Stones Rocks for Collection.

Tufites are volcanic-detritic or volcanic-clastic rocks, mainly formed by pyroclasts and volcanic ash; they are rocks derived from the dismantling of what is poured into areas outside the volcano-tectonic structure.
In petrography we mean a coherent marine or lake sedimentary rock of mixed origin; it is in fact mostly a geologically altered tufa, containing pyroclastic elements associated with detrital elements in a calcareous or clayey cement. In Italy, the dolomitic calcareous tuffs of Livinallongo Formation are of particular importance.

The Livinallongo Formation consists of a stratified complex, of variable thickness (from 0 to 300 m, in lateral heteropy with the limestones and dolomites of the contemporary carbonate platform), of nodular limestones, siliceous-calcareous rhythmites, detrital limestones, tufites ( facies of the "Green Stone of Cadore") of the Lower Ladinian (Middle Triassic), dark gray to green in colour. The formation crops out in the Veneto-Trentina area, mainly straddling the provinces of Trento and Belluno (Agordino, Pale di San Lucano, Civetta group, Val Fiorentina, Val di Fiemme, Val di Fassa, Monzoni group, Pale di San Martino and Cadore).
The Livinallongo Formation was deposited in tropical areas, in progressively subsided basins, surrounded by carbonate platforms. These basin areas were affected by contributions of carbonate material from the platforms and terrigenous material deriving from volcanic activity partly outside the dolomitic area (as evidenced by the tuffaceous levels of "Green Stone"), which settled with turbiditic depositional methods.
Fossils are overall rather rare, even if locally there may be richly fossiliferous levels. Pelagic lamellibranchs (Daonella), cephalopods (Protrachyceras, Trachyceras and Arpadites), echinoderms (Cidaris and Encrinus) and various species of radiolarians are reported in the literature.