Question

state three difference between intrusive and extrusive igneous rocks give examples for both?​

Answer 1

Answer:

Extrusive

Extrusive, also known as volcanic, rocks are a type of igneous rock that form at the crust's surface as a result of volcanic activity. This type of rock occurs when lava flows on or above the Earth's surface and cools down rapidly. The lava comes from the upper mantle layer, 30 to 90 miles beneath the surface, and cools within a few weeks. Because the magma cools and solidifies quickly, the crystals that form do not have time to grow very large, and therefore most extrusive rocks are finely grained. The most common type of extrusive rock is basalt.

Intrusive

Intrusive, or plutonic, igneous rocks form underneath the Earth's surface when magma flows into underground chambers or tunnels. The rock is not exposed to the atmosphere above surface, so the magma cools slowly which allows large mineral crystals to form within the rock. It takes thousands of years for Intrusive rocks to form. A mass of this rock type is called an “intrusion.” Granite is the most common type of intrusive igneous rock.

Answer 2

Answer:

Explanation:

INTRUSIVE                           EXTRUSIVE

magma cools and solidifies                Lava cools on the earth's surface.

beneath the earth's surface.

     Cools very slowly                                      Cools very quickly

       Large crystals                                          Small or no crystals

         Ex: Granite                                                      Ex: Basalt