This volcano is a member of the Stepovak Bay group. From Wood and Kienle (1990) 
: "The Stepovak Bay group is a chain of five volcanoes at the southwest end of a N40 degrees E oriented linear segment of the Aleutian arc on the Alaska Peninsula. This same segment includes the better known Veniaminof and Aniakchak calderas. Three of the Stepovak Bay volcanoes [2, 4, and Kupreanof] have clearly had Holocene eruptions, resulting in three small debris flows filling late Pleistocene glacial valleys, and a small cinder cone and associated lava flow. The other two volcanoes (1 and 3) do not show unmistakable evidence of Holocene activity. They have ice-filled summit craters 500 m (1) and 300 m (3) in diameter that may be late Pleistocene age. These volcanoes have contributed to extensive late Tertiary and Quaternary lava flows, some extending near sea level."