JUNIOR GEOLOGIST Discovering rocks Minerals and Gems S TAMORPHIC WL JUDY MONROE PETERSON Britannica Educational Publishing IN ASSOCIATION WITH ROSEN EDUCATIONAL SERVICES
CHANGED ROCK Rocks are hard materials made up of one or more minerals Metamorphic rocks are one of the three basic types of rock found on Earth The other two types are sedimentary and igneous Metamorphic rock forms from old igneous or sedimentary rock or other metamorphic rock Very high heat and great pressure Pressure is a weight or force that pushes down heavily on something It is caused by gravity Vocabulary Rocks make up Earth’s land surface The three main types from left to right are igneous metamorphic and sedimentary 4
inside Earth’s crust can change old rock into new metamorphic rocks The name metamorphic comes from Greek words meaning change of shape Most metamorphic rocks form slowly over millions of years They come in thousands of different shapes colors and sizes Many mountain chains are made of metamorphic rock People use metamorphic rock such as gneiss and quartzite to make building materials Slate is made into roofing People make statues and buildings from beautiful marble Metamorphic rocks are common in mountain ranges all over the world 5
