There's a seam of volcanic mountains that runs down the center of the Atlantic, but nothing that resembles a supervolcano. The supervolcano complex under the Pacific is one of the largest known in the solar system, however.
reply> There's a seam of volcanic mountains that runs down the center of the Atlantic
replyYeah, that's the pacific rim, which in some sense is the opposite of a volcano.
No the seam at the center of the Atlantic is a mid-oceanic ridge, and it’s very much like a volcano since magma comes out. Icelandic volcanology comes from it being on the ridge.
replyThere are ridges off of the US coast (Explorer, Juan de Fuca, Gorda) but the ring of fire which surrounds the pacific is mostly subduction areas.