The Rock Cycle

By Leilani Drew
Schroeder Skywalker The Rock Cycle Featuring: igneous rocks, metamorphic rocks, and sedimentary rocks Igneous rocks Metamorphic Rocks Sedimentary rocks Intrusive igneous rocks Extrusive Ingneous Rocks Intrusive igneous rocks form inside of earth's crust. The crystals inside of an intrusive igneous rock are usually large, because when the rock cools slowly, the crystals have a lot of time to cool, therefore, the crystals are large! Extrusive igneous rocks form outside of earth's crust. Crystals are small in extrusive igneous rocks because the rocks cool faster in the cooler atmosphere, therefore, making small crystals. Metamorphic rocks are rocks that arise from the transformation of existing rock types, in a process called metamorphism, which means to change in form. Here are some examples of metamorphic rocks This is also gneiss. You might think it is a sedimentary rock, but it is not. The lines on the rock are not layers of minerals, they are cause by pressure. This is called foliation. This is granite. Granite is made of quartz, mica, and feldspar. It is used for landscaping, road base concrete, aggregate fill, stone facings, monuments, countertops, wall tile, sculptures, floor tile, and rock climbing activities. Georgia boasts the largest amount of exposed granite in the world. This is basalt. Basalt is made of pyroxene, olivine, feldspar, and quarts. It is used for in construction (e.g. as building blocks or in the groundwork), making cobblestones (from columnar basalt) and in making statues. Heating and extruding basalt yields stone wool, an excellent thermal insulator. The Columbia Plateau, also known as the Columbia Basalt Plain, formed between 6 million and 16 million years ago as the result of successive flows of basalt. This is gneiss. Gneiss can be made of granite, fedspar, mica, and/or quarts.
It is used for building materials such as flooring, ornamental stones, gravestones, facing stones on buildings and work surfaces. Minnesota contains some of the oldest rocks found on earth. Gneiss can be some 3.6 billion years old, or 80% as old as the planet. This is sandstone.
Sandstone is made of quartz and/or feldspar and sand. Sandstone has been used for domestic construction and housewares since prehistoric times, and continues to be used
for things such as sculpting. Limestone formation occurs all over the island of Jamaica, but especially in the western areas. Sedimentary rocks are formed when plant and animal remains, shells and skeletons of sea life, and bits of older rocks, are cemented, or pressed together. Sediment is often formed when weathering and erosion break down a rock into loose material, and then get pressed together. The Grand Canyon is made up of mostly sedimentary rocks. Grand Canyon and Our Chosen Rock Our chosen rock is Limestone Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate. Many limestones are composed from skeletal fragments of marine organisms such as coral. Limestone has numerous uses: as a building material, as aggregate for the base of roads, as white pigment or filler in products such as toothpaste. Pictures are from google The End