The geology of Jan Mayen is part of the larger Jan Mayen Ridge, an undersea volcanic ridge that forms the boundary of the Iceland Plateau to the northeast. North of the island, the sea floor slopes steeply, plunging a depth of greater than two kilometers in the vicinity of Jan Mayen Rift Zone. The region is highly tectonically active, at the junction of the European and American plates. This activity produces volcanism and earthquakes on the island itself. Beerenberg, a 2.27 kilometer tall volcano rises on the north end of the island, covered in more than 20 glaciers.