Geologically, the area makes up the Cockburn Island Formation, which was studied extensively in the late 1990s by H. A. Jonkers. Rocks found on the island are volcanic, and the island is characterized by its "precipitous cliffs". A "Pecten
conglomerate" from the late
Pliocene or early
Pleistocene period has been identified on the island, situated on a wave-cut platform at 720–820 ft. The island is a rare volcano type called a
tuya, or moberg, which was formed by a three-stage eruption sequence below an ice cap. The first stage was a
subglacial hyaloclastic eruption under a thick ice cap, which shattered the lava into
glass,
ash and sand, which has since weathered to yellow
palagonite layers. The second phase was a lava eruption into a meltwater glacial lake contained in the ice cap, which resulted in volcanic
breccia and
basalt pillow lava (boulders of this can be seen along the shore). The final phase was subaerial basalt lava flows on top of the previous volcanic deposits after the lake drained or boiled away. ==Wildlife==