From Feeley and Winer (1999): "Polovina Hill is a cluster of several scoria cones, the largest of which is ~75 m high with a small water pond occupying the floor of the summit crater. The cone is surrounded by a ring of coarse bombs up to 1.5 m across and the surface is covered by poorly sorted ash, lapilli, blocks, and bombs. A borrow pit on the east flank of Polovina Hill exposes a small cross-section of the interior of the cone, which is characterized by poorly bedded and unconsolidated scoriaceous, red and black lapilli and bombs of various sizes ranging up to 0.5 m across. Sample POL1 is a poorly vesiculataed tachylitic bomb (~25 cm across) collected near the crater rim."
Evidence for fractionation of Quaternary basalts on St. Paul Island, Alaska, with implications for the development of shallow magma chambers beneath Bering Sea volcanoes