Chapter 4. Igneous Rocks. General characteristics of magma. Igneous rocks form as molten rock cools and solidifies General characteristics of magma: Parent material of igneous rocks Forms from partial melting of rocks Magma at surface is called lava. General characteristics of magma.
Basaltic lava dropping into the ocean along Kilauea Volcano along the southeastern coast of the big island of Hawaii
Pumice is very glassy and sharp, with countless vesicles. along the southeastern coast of the big island of Hawaii
Magma evolves as the hotter minerals crystallize and settle to the bottom of the magma chamber