Which rock type is formed from cooling magma or lava?

Which rock type is formed from cooling magma or lava?

• A. Metamorphic Rock
• B. Sedimentary Rock
• C. Fossil Rock
• D. Igneous Rock

Answer: (D)

Rocks are classified by how they form. Igneous rocks come from cooling and solidification of molten rock. When magma cools beneath the surface, it forms intrusive igneous rocks with larger crystals; when lava erupts and erupts on the surface and then cools quickly, it forms extrusive igneous rocks with small crystals or a glassy texture. This process is different from metamorphic rocks, which arise from existing rocks transformed by heat and pressure, and from sedimentary rocks, which form from particles deposited and cemented together or from minerals precipitated from solution. The term “Fossil Rock” isn’t a standard rock category, though fossils can be found in sedimentary rocks.

Rocks are classified by how they form. Igneous rocks come from cooling and solidification of molten rock. When magma cools beneath the surface, it forms intrusive igneous rocks with larger crystals; when lava erupts and erupts on the surface and then cools quickly, it forms extrusive igneous rocks with small crystals or a glassy texture. This process is different from metamorphic rocks, which arise from existing rocks transformed by heat and pressure, and from sedimentary rocks, which form from particles deposited and cemented together or from minerals precipitated from solution. The term “Fossil Rock” isn’t a standard rock category, though fossils can be found in sedimentary rocks.