Mid-Atlantic Ridge pillow basalt
This sample illustrates how pillow basalts grow. First, a pillow structure forms, then increasing magmatic pressure fractures part of the surface. Lava is squeezed through the jagged fracture like toothpaste, forming a striated pillow tube.
Provided by Prof. Charles Langmuir, Lamont-Doherty Earth Observatory, Columbia University, New York, New York
Topic: Earth Science
Keywords: Basalt, Lava, Magmas, Mid-ocean ridges, Ocean bottom, Volcanoes