Rocks

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Rocks:---- Rocks ,naturally occurring solid material consisting of one or more minerals. Rocks are everywhere in the ground, forming mountains and at the bottom of the oceans.

TYPES OF ROCKS: 

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Rocks are divided into three main types, Based on the ways in which they form are as following: Igneous Rocks Sedimentary Rocks Metamorphic Rocks

Igneous Rocks Igneous rocks : Igneous rocks are made of old rocks that have melted within the earth to form molten material called magma.

Sedimentary Rocks 

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Sedimentary rock forms when loose sediment, or rock fragments, hardens. Geologists place sedimentary rocks into three broad categories : 1. Clastic Rocks 2.Chemical Rocks

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Clastic rocks :which form from clasts,or broken fragments, of preexisting rocks and materials. The most common types of clastic rocks are sandstone and shale, also known as mudrock. Chemical rocks : which form when minerals precipitate, or solidify, from a solution, usually seawater or lake water. The most common type of chemical rocks are called evaporites because they form by evaporation of lake water. Organic Rocks: Which form from accumulations of animal and plant remains. The most common organic

Metamorphic Rock 

Metamorphic rock forms when extreme temperatures and pressures deep within the earth alter the mineralogical or structural aspects of existing rock and change it into metamorphic rock.