The volcano rises 2,100 metres (6,900 ft) above the ice level[15] to a maximum elevation of 3,460 metres (11,350 ft).[16][17][3][lower-alpha 3] It is an undissected nearly perfect cone,[5] a 30-kilometre-wide (19 mi) shield volcano[16] with an exposed volume of about 780 cubic kilometres (190 cu mi).[21] The subglacial part, which might bottom out at 1,340–2,030 metres (4,400–6,660 ft) below sea level,[22] could have an even larger volume[21] and is elongated in an east–west direction.[23] On its summit lies a flat, snow-filled 8-kilometre-wide (5 mi) caldera[5] with a 10-metre-wide (33 ft) and 15-metre-high (50 ft) volcanic neck.[24] A lava dome may crop out inside the caldera.