Global Volcanism Program | Image GVP-02367
A crater lake fills Troitsky crater, the youngest of six craters capping the elongated summit of Maly Semiachik volcano in central Kamchatka. Steam rises from the surface of the hot, acidic crater lake in this early 1970s photo. The lake has a maximum depth of about 140 m. Temperatures as high as 41°C have been recorded, along with pH levels down to 0.4.
Photo by Oleg Volynets (Institute of Volcanology, Petropavlovsk).