ブリッジマン島

Bridgeman Island is a small 600 x 900 m remnant of a much larger volcanic edifice that is now largely submerged. It was constructed along the axis of the Bransfield Rift spreading center between the Shetland and Wedell tectonic plates. Bridgeman is located east of King George Island at the NE end of the South Shetland Islands, north of the tip of Graham Land Peninsula. The island has a gently sloping top consisting of truncated lava flows. Steep cliffs surrounding the island expose older lavas and bedded pyroclastic rocks. The extensively eroded volcano does not display youthful volcanic features, although it has been characterized as a now inactive late Pleistocene-Holocene stratovolcano. Several reports of 19th-century fumarolic activity (Catalog of Active Volcanoes of the World) may instead refer to the much younger Penguin Island (González-Ferrán, 1972).