Plosky, a small late-Quaternary basaltic shield volcano that was constructed about 20 km W of the crest of the Sredinny Range, is the westernmost volcano of the northern Sredinny Range. It is located immediately north of the large Pleistocene Tekletunup volcano. Early geologic studies in the Sredinny Range (Ogorodov et al., 1972) identified numerous Holocene eruptive centers based primarily on morphological criteria. However, later work has suggested that Sredinny Range volcanoes are less mantled by Holocene tephras than eastern Kamchatka volcanoes and therefore appear more youthful, so that Holocene eruptions are uncertain for many of these Sredinny Range eruptive vents.