ROCK FORMATION

Rock formations are created millions of years of weathering and erosion by the elements such as heat, wind, rain and occasional volcano.

Our planet is chock full of beautiful and bizarre rock formation. Access the link to some incredible pictures of rock formation

The main types of rock  and the differences among them have to do with how they are formed. 

IGNEOUS ROCKS

Examples Granite, Basalt, Obsidian, Pumice
Igneous rocks are formed from molten magma or lava. The word, igneous means, "fire". All igneous rock starts deep in the earth as hot, molten magma.
If the magma cools and hardens inside the earth it is called "intrusive" rock. These rocks cool slowly and have large crystals. When the magma comes out of the earth's crust through a volcano, it is called "extrusive". It cools off quickly, and the crystals that form are very small.
Molten, or hot, liquid rock is called MAGMA when it is still inside the earth, but once it comes out through a volcano it is called LAVA.


SEDIMENTARY ROCKS

Examples Limestone , Jasper, Gypsum, Conglomerate, Sandstone
Every minute of every day, rocks are being worn down by wind and rain. Tiny grains of dirt, sand, mud and clay are worn off and washed into streams, rivers, lakes and oceans. When these tiny bits of sand and dirt settle to the bottom of the water, they are called sediment.
Minerals in the water and microscopic, or very tiny sea animals also get mixed in with the dirt and sand to form the sediment. Every day more sediment piles on top of what is already there.
After thousands and millions of years we end up with a really deep pile of sediment. The weight and pressure from all the stuff on top turns the sediment on the bottom into sedimentary rock!


METAMORPHIC ROCKS

Example Quartz, Amethyst, Marble, Slate, Gneiss, Graphite
Metamorphic rocks are formed when other kinds of rocks are changed by great heat and pressure inside the earth.
The word "metamorphic" means changed. Think of metamorphic rocks as recycled rocks. When igneous, sedimentary or even metamorphic rocks get buried deep beneath the surface of the earth, over millions of years the heat and pressure inside the earth change them into something else.
Limestone can be changed to marble, sandstone can be changed into quartzite, and shale can be changed to slate. It's just another example of how the earth is constantly changing!


TRANSPORTATION OF ROCKS

As rocks are broken down by chemical and physical forces, particles become increasingly smaller. The particles are transported through rivers and by wind. The three main sizes of soil include sand, silt, and clay. Soil formation occurs due to the change in particle size, organic matter, and the movement of elements and minerals. The four major influences on soil are weathering, climate, land surface, and living organisms.

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