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TYPES OF ROCKS



                       Many of the materials we use every day are made from different kinds of rocks.

                       On the basis of their mode of formation , rocks are classified into three categories :
                               IGNEOUS  ROCKS





                              SEDIMENTARY ROCKS




                              METAMORPHIC ROCKS




               1.  IGNIOUS ROCKS:
                    All rocks on earth were initially igneous in nature.
                    Rocks  formed  by  the  solidification  (due  to  cooling)  of  volcanic  eruptions  (lava)and
                      magma.

                    The interior of the earth consists of molten material called magma.
                    Magma that reaches the surface of earth is known as lava.
               2.  SEDIMENTARY ROCKS:
                    These  rocks  are  formed  by  the  deposition  of  the  material  (sediment)  present  at  the
                      earth’s surface.
               3.  METAMORPHIC ROCKS:
                    Rocks  formed  by  the  transformation  of  igneous  or  sedimentary  rocks  into  different
                      kinds of rocks under intense heat and pressure.
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