“…4). The uppermost Permian succession comprises alternating tuff, tuffaceous sandstone and basalt flows up to 350 m thick (Pogrebitskiy and Lopatin, 1999a,b (Data sources: Grigorieva, 1983, 1986;Budnikova et al, 1991;Bulgakova, 1967;Egorov, 1993;Egorov and Andreev, 1981;Ershova et al, 2012Ershova et al, , 2014Gogina, 1979;Kalinko, 1953;Kontorovich et al, 2013;Matukhin, 1991;Matukhin et al, 1995;Menner and Sidyachenko, 1975;Mezhvilk and Markov, 1983;Pogrebitskiy and Lopatin, 1999a,b;Pogrebitskiy and Shanurenko, 1998a,b;Prokopiev et al, 2001;Proskurnin et al, 2013;Shishlov et al, 1997;Sobolev, 1997Sobolev, , 1999Solomina, 1997;Vanin et al, 2001;Yazikov et al, 2013).…”