Five jaw-dropping facts from the ocean’s deepest trenches

Mariana forearc has at least 19 active serpentinite mud volcanoes venting cold, hyperalkaline fluids with pH up to 12.6.

Excess trench sediments may help trigger great earthquakes, and 13 of 19 huge events fit that pattern.

The hadal snailfish survives by losing its swim bladder and making TMAO to stabilize proteins under pressure.

Deep trench seep fields host the deepest, most extensive chemosynthetic communities yet reported, reaching 9,533 meters across about 2,500 kilometers.