During the October 2011 eruption of El Hierro volcano, hundreds of steaming volcanic "bombs" appeared floating on the sea surface about 1.2 miles (2 kilometers) offshore La Restinga village. Tiny marine fossils encased in the lava fragments could reveal when El Hierro volcano, a new study suggests. Here are amazing images of the eerie rocks.
Another view of lava bombs offshore El Hierro in 2011. (Photo credit: Valentin Troll, Uppsala University)