Rocks minerals and mixtures

1. Rocks minerals and mixtures By: Christopher Arizzi Jr. and Brian Carnes

2. Section 1 Vocabulary • Rock: a solid mixture of crystals of 1 or more minerals. • Rock cycle: process by which 1 rock type changes into another. • Magma: hot liquid that forms when rock partially or completely melts. • Composition: minerals a rock is made of. • Texture: determined by the sizes, shapes, and positions of the grains. • Igneous rock: rock that forms from the cooling of magma. • Sedimentary rock: rock that forms when sediments are compacted and cemented together. • Metamorphic rock: rock that forms when the texture and composition of the preexisting rock is changed by heat or pressure.

3. Rock Cycle

4. Igneous Rocks • The original sand grains from step 1 have changed a lot, but they’re not done yet! Magma is usually less dense than the surrounding rock, so it tends to rise to higher levels of the earth’s crust. Once there, it cools and solidifies, becoming igneous rocks.

5. Sedimentary Rocks • Grains of sand and other sediment are eroded from the mountains and wash down a ricer to the sea. Over time, the sediments forms thick layers on the ocean floor. Eventually, the grains of sediment are pressed and cemented together, forming sedimentary rocks.

6. Metamorphic Rock • When large pieces of the earth’s crust collide, some of the rock is forced downward. At these lower levels, the intense heat and pressure “cooks” and squeezes the sedimentary rock, changing it into metamorphic rock.

7. Section 2 vocabulary • Intrusive: when magma cools beneath the Earths surface. • Extrusive: rock that forms on Earths surface.

8. Image of igneous rocks solidifying

9. Dikes

10. Credits • Holt Science Book • http://upload.wikimedia.com • Microsoft Clip Art