Lōʻihi began forming around 400,000 years ago and is expected to begin emerging above sea level about 10,000–100,000 years from now. At its summit, Lōʻihi Seamount stands more than above the seafloor, making it taller than Mount St. Helens was before its catastrophic 1980 eruption. A diverse microbial community resides around Lōʻihi's many hydrothermal vents.