Copy of The Cycle of Rocks - Cbot
Sedimentary rocks are formed from sediment. This sediment can be pebbles, shells, sand, and other small pieces of material. Sedimentary rocks are often soft, break apart, and crumble easily. A lot of times you can see stones and sand in the rock, and it is the only type of rock that contains fossils. Examples of sedimentary rocks are conglomerate and limestone.
Metamorphic rocks are formed under the Earth's surface from metamorphosis that happens from heat and pressure. Metamorphosis can occur when rock is heated at 300 to 700 degrees Celsius. The rocks that result from this process often have layers and may have shiny crystals formed on their surface by minerals which grow slowly over time. Examples of metamorphic rock are gneiss and marble.
Sometimes these metamorphic rocks are pushed back into the earth, melt and turn into magma and the cycle starts all over again!
Sources:
http://www.learner.org/interactives/rockcycle/
Images: Google Images, Geology.com
Cycle of Rocks
SEDIMENTARY ROCK
By : Colin Sandee
EROSION AND SEDIMENT
The rocks that are on the Earth's surface can be broken down into pieces by wind and water. The wind and water can take the rock to another place, this is called erosion. These pieces of rock are called sediment. Sediment drops from the wind and water to form a layer. Over a long period of time there can be many layers of sediment, and these can harden into sedimentary rock.
IGNEOUS ROCK
Magma cools and makes crystals which turn into igneous rock. Igneous rock can be formed underground where the magma cooks for a long time. It can also be formed above ground where it cools for a short period of time. Sometimes when it cools quickly then the crystals do not form which makes the rock look like glass. Gas bubbles sometimes form in the rock leaving holes in it. Basalt and Obsidian are types of igneous rocks.
Introduction
This is a presentation about the rock cycle which I have called "The Cycle of Rocks". In this presentation I will show and describe the five parts of the rock cycle. I will also show and describe the different types of rocks within each cycle.
HEAT AND PRESSURE
Inside the Earth there is heat and pressure. The heat comes from friction caused by the movement in the Earth's crust. Rocks get pushed down in the Earth where it is hotter which then change the rock, this rock is called metamorphic rock.
MAGMA
The first part of the rock cycle I am going to describe is magma. The magma is located in the Earth's core. The magma rises up to the Earth's surface and cools, and sometimes it erupts from a volcano. Magma is a hot liquid made of melted minerals. When magma pours out of the volcano it is called lava. As the magma cools it hardens and forms igneous rock.