igneous
/ˈɪɡnɪəs
/adjective Geology
1(Of rock) having solidified from lava or magma.The occurrence of these felsic extrusive igneous rocks potentially provides key information on the complex interplay of magmatism and tectonics....
- This heat gradually accumulates and eventually causes localized eruptions of basaltic magmas (molten igneous rock).
- The prevalence of Late Jurassic subduction-related igneous rocks indicates that arc formation and accretion orogeny were the most important processes during the evolution of this part of the Internal Hellenides.
1.1Relating to or involving volcanic or plutonic processes: igneous activity...
- The layering in these ultramafic rocks, and their position above mantle tectonites, is attributed to lower crustal igneous processes.
- However, enormous emphasis has been placed on them for understanding igneous processes and the evolution of Earth.
- On Macquarie Island there's very similar kind of geology, as I'm sure Rick has described; we have mantle rocks and evidence of punctuated deformation events in igneous activity.
1.2 rare Of fire; fiery.It is an igneous or fiery aura, not indeed in the open act of combustion, but composed of the finest and most minute particles of a peculiar species of elementary fire.
Origin
Mid 17th century: from Latin igneus (from ignis 'fire') + -ous.