Igneous rocks are formed from melted rock deep inside the earth. Sedimentary rocks are formed from layers of sand, silt, dead plants, and animal skeletons. Metamorphic rocks formed from other rocks that are changed by heat and pressure underground.
Rocks Are Grouped into Three Classes Depending on How the Rock Was?
Rocks are a naturally occurring solid material composed of several minerals, and they are often classified into three distinct categories depending on how they were formed. The first class of rocks is igneous rocks, which are formed from molten magma deep within the Earth’s crust. The second class of rocks is sedimentary rocks, which are formed from the erosion of existing rock and the deposition of sediment. The third class of rocks is metamorphic rocks, which are formed when sedimentary or igneous rocks are exposed to extreme temperatures and pressures.
Igneous rocks are the oldest type of rocks and are formed when molten magma cools and hardens. Magma is the molten material that lies beneath the Earth’s surface and is composed of melted minerals and gases. Igneous rocks are further classified based on their texture and mineral makeup. For example, some igneous rocks are composed of large, easily distinguishable crystals, while others are composed of tiny, microscopic crystals. Examples of igneous rocks include granite, basalt, and obsidian.
Sedimentary rocks are formed when existing rocks are eroded away by wind, water, and other forces of nature, and the eroded particles are deposited in layers. Over time, the layers of