East Pacific Rise pillow basalt | AMNH https://www.amnh.org/exhibitions/permanent/planet-earth/why-are-there-ocean-basins-continents-and-mountains/non-explosive-volcanism/volcanoes-under-the-sea/east-pacific-rise-pillow-basalt2
This sample illustrates the hollow nature of many pillow basalts.
plates move past each other Anza-Borrego Atlantis