Lava spills from ‘smiling’ volcano into the sea
Geology is an odd mix of incredibly slow processes over hugely long periods of time, and abrupt, immediate changes happening right now. While Canada and Australia vie for the title of who has the oldest rock from when the Earth’s crust was still hot and young, Hawaii and other island volcanoes are in a constant competition for the freshest, newest rock around. When the lava meets the sea, it cools quickly while boiling the ocean into steam. This results in a distinctive texture: the quenching produces a glassy outer surface from the lava cooling too quickly for crystal structure to grow. This insulates the inside of the globs, trapping any dissolved gas as bubbles and allowing internal microcrystal growth from the slightly slower cooling rate.