The Hawaiian Islands' youngest volcano is still well below the ocean and likely won't make its fiery debut for another 10,000 years or more, if at all. It has been growing at an average rate of 0.1ft per year over its 400,000 year life span. Although an eruption caused a swarm of over 4,000 earthquakes in 1996 (three of which rattled the residents of Kaʻu), lately Lo'ihi has been relatively quiet, and its summit is still 3200ft below sea level.
A 2014 expedition to map and study Loʻihi sampled unique iron-eating bacterial mats found at the base of the mountain – a crushing 3 miles under the ocean.
