Achilled margin is a shallowintrusive orvolcanicrock texture characterised by aglassy orfine-grained zone along the margin where themagma orlava has contacted air, water, or particularly much cooler rock. This is caused by rapid solidification of the melt near the contact with the surrounding low temperature environment. In an intrusive case, the crystallized chilled margin may decrease in size or disappear by later remelting during magma flow, depending on magmaheat flux.

The feature is often seen indikes orsills, and especially insheeted dike complexes, where multiple chilled margins are a distinctive feature.

Pillow lavas often show such chilled margins which are glassy and prove the sudden cooling undergone due to contact with water.

• H.E. Huppert and R.S.J. Sparks (1989): Chilled margins in igneous rocks. Earth and Planetary Science Letters, volume 92, issues 3–4, pages 397-405.

This article aboutigneous petrology is astub. You can help Wikipedia byexpanding it.

• v
• t
• e

• Igneous petrology
• Igneous petrology stubs

• Articles with short description
• Short description matches Wikidata
• All stub articles