A magma chamber is a structure made up of solidified crystal mush and molten rock located below the surface of the Earth. When a magma chamber solidifies and cools, it is known as a pluton.
Magma is made of fresh materials from regions located near the surface of the Earth and re-melted material from the Earth’s crust. When this magma erupts in lava form, it converts into silicate rock. Each eruption from a volcano changes a chamber's chemical composition. Scientists study the different layers of the lava flows from volcanoes to examine the chemical changes of magma in the chambers.