Tuesday, March 22, 2016 B-Day Objective: YWBAT determine the visual differences between igneous, sedimentary, and metamorphic rocks. Drill: Do you think rocks that cooled and solidified from lava on Earth’s surface would look different from those that cooled and solidified from magma inside the Earth? Explain your answer. Homework Study WOW Check Power School Answer Extrusive – Lava that cools and solidifies on the Earth’s surface forms an Igneous Rock with a fine grained texture Instrusive – Magma that cools and solidifies inside the Earth’s surface forms Igneous Rock with a course grained texture DiD you know…? Pumice is an unusual, lightweight rock formed when molten rock is rapidly blown out of a volcano, forming bubbles as it quickly loses pressure and cools at the same time. Today’s Activities Drill Read pages 87 – 90 WOW Review Questions page 90 Conclusion Closure Question How does the cooling rate of lava or magma affect the texture of an igneous rock? Conclusion Answer When magma cools slowly, crystals have a long time to grow, so the igneous rock that forms is course-grained. When magma cools quickly, crystals have a short time to grow, so the igneous rock that forms is fine-grained.