Plutonism

Plutonism is a scientific theory that explains the origin of rocks, particularly igneous rocks, as having solidified from magma deep within the Earth. This theory was championed by James Hutton in the 18th century, contrasting with the Neptunian theory, which proposed that rocks formed from sediments deposited in a primordial ocean.1

Plutonists believed that subterranean heat played a crucial role in Earth's dynamic processes, causing the expansion and uplift of landmasses. Hutton recognized granite as an intrusive igneous rock, formed by magma cooling beneath the surface, providing evidence for this internal heat. A pluton itself is defined as a body of intrusive igneous rock, often large, whose exact characteristics may be uncertain. Adherents to this theory are known as plutonists.1234