Find-A-Feature: Vesicles

Holes in rocks? How did they get there? What do they mean? For this Find-A-Feature challenge, we challenge you to look around you for examples of vesicles.

Vesicles are the small holes left behind after lava cools and turns into volcanic rock. Vesicles help geologists understand the cooling history of extrusive (volcanic rocks) because lava contains large amounts of dissolved gases that are released as the lava hardens. A similar process can be seen when bubbles created by yeast are released in the bread-baking process or when dissolved carbon dioxide is released when a can of soda is opened. What do you see around you that forms in this way?


We'll be watching Instagram and Twitter for some great #findafeature examples and may share them here with the first name or initials of the contributor, and a general location. If you tag us with @USGS_YES you are giving us permission to use your image. Please see the USGS social media sharing policy at: Or, you can e-mail photos to us at and we may share them on this page or on social media. Thanks for participating and for seeing science all around you!