What are igneous rocks?

Igneous rocks are a type of rock that is formed from the cooling and solidification of magma or lava. Magma is molten rock that is found beneath the Earth's surface, while lava is molten rock that erupts onto the Earth's surface.

Formation process

When magma or lava cools and solidifies, it forms igneous rocks. This process can happen either underground (intrusive rocks) or on the Earth's surface (extrusive rocks). Intrusive rocks are formed when magma cools slowly beneath the Earth's surface, while extrusive rocks are formed when lava cools quickly on the Earth's surface.

Types of igneous rocks

There are two main types of igneous rocks: volcanic rocks (extrusive) and plutonic rocks (intrusive). Volcanic rocks such as basalt and pumice are formed from lava cooling quickly on the Earth's surface, while plutonic rocks like granite and gabbro are formed from magma cooling slowly beneath the Earth's surface.

Characteristics

Igneous rocks are known for their interlocking crystalline structure and often contain mineral compositions such as quartz, feldspar, and mica. They can vary in color, texture, and density depending on their mineral composition and formation process.

In conclusion, igneous rocks are a fundamental part of the Earth's geology and play a crucial role in understanding the planet's history and volcanic activity.