These tiny, crackly bubbles are a new type of volcanic ash

Called bread-crust bubbles, this ash consists of millimeter-long spheres with a crackled surface

bread-crust bubble ash samples

LAVA BUBBLES  Researchers have discovered a new kind of ash, dubbed bread-crust bubbles, which are tiny spheres of ash no more than a millimeter in diameter that form deep underground.

S. Quane and B. Andrews/Smithsonian Institution

This article is only available to Science News subscribers.

Subscribers, enter your e-mail address to access our archives.

Not a subscriber?

Science News is a nonprofit.

Support us by subscribing now.

More Stories from Science News on Earth

From the Nature Index

Paid Content