plutonism
/ˈpluːtəˌnɪzəm/
noun
- A theory in geology that most rocks, especially igneous rocks, were formed by the cooling of molten magma from inside the Earth.
- Modern geology accepts plutonism as the process behind volcanic rock formation.
- The debate between plutonism and neptunism shaped early geology.
- Plutonism was a major scientific idea in the 18th century that explained how granite forms.