extrusive rock
Definitions
Igneous rock formed from magma that has erupted onto the Earth's surface and cooled rapidly.
Volcanic rock characterized by a fine-grained or glassy texture due to quick solidification.
Examples
Basalt is a common type of extrusive rock formed from the rapid cooling of lava on the Earth's surface.
Geologists studied the volcanic landscape to identify various samples of extrusive rock scattered across the crater.