1
زمینشناسی و معدن::
سنگ مذاب-گداخته شده
Magma: Parent Material of Igneous Rock Our discussion of the rock cycle in Chapter 1 explained that igneous rocks (ignis =fire) form as molten rock cools and solidifies.
Occasionally, molten rock reaches Earth's surface, where it is called lava (Figure 4.1).
The Nature of Magma Magma is completely or partly molten rock, which when cooled solidifies to form igneous rocks composed mainly of silicate minerals.
Molten rock may crystallize within Earth's crust over a range of depths, or it may solidify at Earth's surface (Figure 4.3).
Igneous rocks that form when molten rock solidifies at the surface are classified as extrusive igneous rocks.
واژگان شبکه مترجمین ایران