There are three primary classifications of rocks, including sedimentary rocks, igneous rocks and metamorphic rocks. Discover how all three main types of rocks are formed with help from a lab manager and research scientist in this free video on identifying rocks.
Promoted By Zergnet
Hi I'm Jane Stammer, a research facility at the Colorado School of Mines and I'm here to answer your questions on geology. Our first question is how to classify rocks. There are three main classifications of rocks. There are sedimentary rocks, igneous rocks and metamorphic rocks. Igneous rocks are formed both underground and aboveground when big pools of magma crystallize and form minerals which later coalesce to form different rocks. Metamorphic rocks are formed at very high temperatures and pressures deep, deep under the ground and at these high temperatures and pressures, the rocks actually melt and recrystallize and metamorphose into new and different rocks. And finally sedimentary rocks are formed from the erosion and later deposition of preexisting rocks that are deposited in low lying areas and later compacted over time. And that is how to classify the three main types of rocks.