Relatively soft, porous rock that is usually formed by the compaction and cementation of volcanic ash or dust. Tuff may vary greatly not only in texture but also in chemical and mineralogical composition. In some eruptions, foaming magma wells to the surface as an emulsion of hot gases and incandescent particles; the shredded pumice-like material spreads swiftly, even over gentle slopes, as a glowing avalanche (nuée ardente) that may move many miles at speeds of 100 mph (160 kph)
a general term for all consolidated pyroclastic rocks, but usually referring to the finer-grained variety; the coarser variety usually is called volcanic breccia
A term applied to compacted deposits of the fine materials ejected from volcanoes, such as more or less cemented dust and cinders Tuffs are more or less stratified and in various states of consolidation They are prevalent in the Mediterranean area
tuff
Турецкое произношение
tʌf
Произношение
/ˈtəf/ /ˈtʌf/
Этимология
[ 't&f ] (noun.) 1815. Middle French tuf, from Old Italian tufo.