ALL ABOUT ROCKS
BUILDING BACKGROUND • Here you’ll learn about three different kinds of rock and how they are formed. You will also learn how to make observations and practice interpreting observations.
BUILDING BACKGROUND • What does this remind you of? • Have you ever seen or visited a place like this? • What do you think made those rocks?
THE BIG IDEA • Rock can form on Earth or below its surface. Earth has three kinds of rock. Each kind of rock can turn into another kind of rock. The rock cycle shows how rock changes.
IGNEOUS ROCK • Igneous rock- forms in Earth’s crust when magma cools and hardens.
SEDIMENTARY ROCK • Sedimentary rock- forms on Earth’s surface when bits and pieces of rock and other things get stuck together.
METAMORPHIC ROCK • Metamorphic rock- is formed when any rock is changed by heat and pressure with Earth.
KEY CONCEPTS • Sedimentary is a word that relates to sediment, or small pieces of rock, shell, or bone. Sedimentary rock is made of small pieces of rock that get pressed together over millions of years. This happens on the surface of Earth.
KEY CONCEPTS • Igneous is a word that relates to fire. Igneous rock is made of melted rock that cools and hardens. This usually happens on or near the surface of Earth.
KEY CONCEPTS • Metamorphic is a word that relates to change. Metamorphic rock comes from the actions of heat and pressure on other kinds of rock. This always happens deep inside Earth.
HOT MAGMA • Rock deep inside Earth is soft and hot. It may melt and become magma.
HOT LAVA • This melted rock is so hot that it glows red and orange. This is called a lava flow.
COOLING LAVA • Lava cools when it meets the air. The surface of this lava is black and crusty.
COOLED ROCK • This black rock is from lava that has cooled. The lava cooled slowly. How can you tell?