Rocks
Igneous rocks
Igneous rocks are formed when lava cools and becomes solid. Magma is melted rock found deep below earth’s crust. When temperatures and pressures are high any rock can turn into magma. Lava is melted rock on earth’s surface. Igneous rocks can be ether intrusive, which means they are formed in the earth, or extrusive, which means that they are formed on the earth.
Sedimentary rocks
Sedimentary rock is made from sediment and by chemical reactions. Sediment is loose material such as bits of rocks, minerals, plants, and animals. Water, wind, and ice can move sediment to the place where it settles. Sediment slowly settles on the top of other sediments forming layers. Sedimentary rocks are often formed in oceans and lakes where the larger and heavier fragments settle first. Each layer of sediment is squeezed together by the weight above it, the process of the sediment squeezing together is called compaction.
Metamorphic rocks
If you find a rock with lots of shiny mica parts, cleavage and many layers then you may have found a metamorphic rock. A metamorphic rock is made when heat, pressure, or land fluids change one type of rock into another type of rock. Metamorphic rocks can be made from igneous and sedimentary rocks, and form metamorphic rocks. The formation of the metamorphic rock is long and slow.
Rock cycle