It would become a nuclear volcano and would likely end all life on earth since volcano ash travels extremely far distances in the atmosphere and would be contaminated with nuclear radiation It would also likely trigger earthquakes and tsunamis It would be Chernobyl reactors exploding but a million times worse Since it’s a volcano and as I said the ash would travel across the globe spreading deadly radiation The ash would kill everything it touches basically since it would be soaked with nuclear radiation It would be Armageddon to sum it up The explosion would definitely cause the volcano to erupt by force alone