Rock Cycle Essay

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The Rock Cycle The rock cycle is a concept used to explain how the three basic rock types are related and how they help processes Earth and how rocks change from one type of rock into another type of rock. Rocks change shape, form and type by a few different causes. One of the causes is by plate tectonic activity, movement of Earth’s surface in the present and the past. Another cause is by weathering, wear away or change the appearance or texture of by long exposure to the air. The last type of cause is the erosional processes, a type of weathering in which surface soil and rock are worn away through the action of glaciers, water, and wind. There are three classified types of rocks. They are classified based on how they form. The first form …show more content…
They are formed by the solidification of molten rock material and there are two types of igneous rocks, intrusive igneous rocks and extrusive igneous rocks. Intrusive igneous rocks are crystallized below Earth’s surface. Examples of intrusive igneous rocks are basalt, volcanic glass, granite, pegmatite, and gabbro. Basalt consist of microscopic mineral crystals that indicate a history of rapid cooling. They have small holes or vesicles that are frozen shells of carbon dioxide and water vapor gas bubbles. These holes were created as these gases exited the lava. Volcanic glass, also known as obsidian, often forms in lava flows where cooling takes place so fast that crystals do not have time to grow, therefore volcanic glass has no crystal structure and fracture in smooth curved shapes. This type of rock was used to make tools, arrow heads, and weapons. Granite is the most common rock found in the Earth’s continental crust. It is a lights colored igneous rock with grains large enough to be visible without the use of a microscope. Granite forms from the slow crystallization of magma below Earth’s surface and is composed mainly of quartz and feldspar. Pegmatite is a very coarse to gigantic grained igneous rocks. Most pegmatites have the same minerals as granite but with larger crystals. Gabbro is an igneous rock that has large crystals formed by slow cooling of magma deep …show more content…
This is a classification of rocks that formed as a result of the weathering process by compaction or cementation of rock and mineral fragments or the precipitation of dissolved minerals. Types of sedimentary rocks include chert, limestone, mudstone, sandstone, and conglomerate. Chert is a rock that looks a lot like Ocala lime stone and actually started out as a limestone. Chert is common in Florida and used to make stone arrowheads, spear points, knives, axes, and other tools. Limestone comes in a lot of different forms, but all are made of the mineral calcite. Most limestones develop in shallow, warm marine waters where they accumulate shells, coral, and algal allowing them to later create fossils. Mudstone is made up of tiny clay particles that can only be seen under a microscope. Mudstone can be similar to sandstones with the exception of the grain sizes that are the size of silt and clay particles. Mudstone is found in very still water, this is because grains this small are able to settle only in very still water, for example, lagoons, estuaries, flood plains, and river deltas. Sandstone is a sedimentary rock made of sand sized grains of mineral, rock, or organic material. This is the most common sedimentary rock found in basins all around the world. It is mined for construction material or material used in manufacturing. Conglomerate is made of large round clasts with spaces between the clasts that are filled with smaller

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