Types of Rocks

There are three major types of rocks, which are:

1. Igneous Rocks
2. Sedimentary Rocks
3. Metamorphic Rocks

Igneous Rocks

Igneous rocks are formed from the cooling and solidification of magma or lava. Magma is the molten rock that is found beneath the Earth's surface, while lava is the magma that has erupted onto the Earth's surface. Igneous rocks are classified based on their texture and composition. Some examples of igneous rocks are granite, basalt, and pumice.

Sedimentary Rocks

Sedimentary rocks are formed from the accumulation of sediments, which are particles of rock, mineral, and organic matter that have been weathered and eroded from other rocks. The sediments are transported by water, wind, or ice and are deposited in layers. Over time, the layers become compacted and cemented together to form sedimentary rocks. Some examples of sedimentary rocks are sandstone, limestone, and shale.

Metamorphic Rocks

Metamorphic rocks are formed from the transformation of existing rocks through heat, pressure, and chemical reactions. The original rock, called the protolith, is subjected to these forces, causing it to change into a new type of rock. Metamorphic rocks are classified based on their texture and the type of protolith they were formed from. Some examples of metamorphic rocks are marble, slate, and gneiss.

Mantle Rocks

The mantle is the layer of the Earth that lies between the crust and the core. It is composed of rocks that are mostly solid, but can flow like a thick liquid over long periods of time. The rocks in the mantle are not considered a separate type of rock, as they are not exposed at the Earth's surface and are not easily accessible for study. Therefore, mantle rocks are not one of the major types of rocks.