Deep-ocean trenches (DOT’s)
Sea floor is very deep, >6 km and often ~10 km deep
Narrow, typically ~5 km wide at their base
Have long, arcuate traces on map or globe
Have a characteristic asymmetric V shape, with a gentle seaward slope, a pointed base, and steeper slope that rises to an arcuate string of volcanic islands or a string of evenly-spaced continental volcanoes
Volcanoes may explosive, i.e. Mt. St. Helens or Mt. Pinatubo