EVERYDAY SCIENCE

Detailed explanation-1: -Extrusive, or volcanic, igneous rock is produced when magma exits and cools above (or very near) the Earth’s surface. These are the rocks that form at erupting volcanoes and oozing fissures.

Detailed explanation-2: -When lava reaches the surface of the Earth through volcanoes or through great fissures the rocks that are formed from the lava cooling and hardening are called extrusive igneous rocks. Some of the more common types of extrusive igneous rocks are lava rocks, cinders, pumice, obsidian, and volcanic ash and dust.

Detailed explanation-3: -Igneous rocks come from melted rock material, or magma, that lies beneath Earth’s surface. Igneous rocks form when magma from inside the Earth moves toward the surface, or is forced above the Earth’s surface as lava and ash by a volcano. Here it cools and crystallizes into rock.

Detailed explanation-4: -Granite and basalt are the two most abundant igneous rocks at the earth’s surface. Magma/lava is a mixture of elements such as silica, iron, sodium, potassium, etc. As the magma/lava cools these elements chemically combine, or crystallize, in geometric patterns to form the eight rock forming minerals.

Detailed explanation-5: -Igneous rocks form when molten rock (magma or lava) cools and solidifies. Sedimentary rocks originate when particles settle out of water or air, or by precipitation of minerals from water.