Littoral (or steam) explosions occur when hot lava enters the sea along a shoreline, which is also known as a littoral zone. In this image we see an explosion of lava fragments showering into the air, most likely above an open vent in a lava tube system, bursting out as a lava bubble, then showering molten fragments to earth around the vent, eventually forming a cone. Other fragments fall into the sea, where they are carried by ocean currents and deposited in bays to form black sand beaches. This view is from the coastal village, Kalapana, on Hawaii's southeast coast.