Discovery Box
GEOLOGY ROCKS!
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by Andrea Willingham, the UO Museum of Natural and Cultural History Illustrations by Liz White
he Pacific Northwest is home to some truly fascinating geology. From the coast to the mountains to the high desert, the region’s rocks and landscapes tell amazing stories about the Earth’s deep past. Did you know that rocks are changing all the time? Even though they look like they’re always the same, they’re actually transforming very slowly, over millions of years, through a process called the rock cycle. Let’s explore the rock cycle and see how it works. It all starts with the three types of rocks that make up planet Earth: igneous, sedimentary, and metamorphic. Igneous rocks form when magma—the hot liquid rock that flows underneath Earth’s surface—cools and hardens. Basalt, granite, and obsidian are all
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S E P T E M B E R 2 0 2 0 • O R E G O N F A M I LY. C O M