Rock Cycle Smith

Rocks Naturally occurring solid mixture of one or more minerals and organic matter. Rocks continually change through a process called the rock cycle. A rock’s value is based on the mineral that make it up. Example….Gold, Granite, quartz are all popular. Rock or Rocks make up most of the earth.

Rock Cycle the rock cycle works in a pattern or circular rotation. There is not a definite starting point or ending point. Weathering is a huge part of the rock cycle. Weathering is the breaking down of rocks by water, wind, ice, heat. Erosion is also a process that helps drive the rock cycle. Erosion is the when water, wind or gravity take sediment from its location.

Rock Cycle As rocks are broken down by weathering, the pieces become sediment or small fragments of rock that make up soil. Soil is made up of sediments, dead and decomposed matter. From that point the Rock Cycle process begins. The Rock cycle produces 3 types of rocks: Sedimentary, Metamorphic and Igneous

Sedimentary Rocks Sedimentary rocks are called Sedimentary because they are made of sediments. As sediments are buried and squeezed by the weight above it, the pressure forms a rock of the sediments. The sediments can be seen very clearly and usually feel very rough.

Sediments Sediments are anything that has been weathered or eroded. Sediments come in all sizes. Sand, Mud and dirt are made of sediments. Sediments are usually made of the rocks around them. As more sediment piles on top of other sediment, the sediments sink into the ground and become cemented by the pressure of the dirt and ground above them, this is called Cementation.

Sedimentary Rock As the sediments from earth’s crust are pressured and heated, they are then cemented to become rock. Sedimentary rocks can be made of organic matter and other mineral sediments. Sedimentary rocks can preserve fossils. As sediments layer on top of each other they can trap animal remains and shells or anything hard enough to not be decomposed.

Metamorphic Rocks Sedimentary rock can change to metamorphic rocks by adding pressure and heat. Metamorphic is the stage between sedimentary and igneous where temperatures are high enough to melt the sediments together and change the composition.

Metamorphic rocks form when the chemical composition of the rock changes due to extreme heat and pressure. The minerals inside of rocks react different to heat and pressure causing them to form into all kinds of rock after being exposed to heat. For example: Quatz, which is like glass can turn into Garnet. Garnet is like a ruby.

Igneous Rocks As sedimentary rocks sink deeper into the ground the temperature begins to increase and get hotter. This heat melts the sedimentary rock into magma. The magma then flows to earths surface, cooling and creating Igneous rocks. Igneous rocks always need extreme heat and pressure to transform from sedimentary to igneous.

Remember……. Remember it takes EXTREME heat and pressure to convert sediments into a mineral or a sedimentary rock into a metamorphic rock or metamorphic rock into a Igneous rock. Metamorphic and Igneous rocks can be turned back into sedimentary rock simply by erosion and weathering. So the only way for a rock to change in the rock cycle is to encounter extreme heat and pressure or to be weathered/eroded.