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Remember that the three types of rock are: · sedimentary - formed when sediment hardens · igneous - formed when magma hardens · metamorphic - formed from intense pressure under the Earth's surface In what type of rock are imprints and mineralized fossils created? Can you exclude one type of rock right away?
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· sedimentary - formed when sediment hardens · igneous - formed when magma hardens · metamorphic - formed from intense pressure under the Earth's surface Metamorphic rock forms deep under the Earth's surface. Things
- n top of the Earth (like a
dinosaur) would not be in contact with metamorphic rock. There are three major types of rocks
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That leaves sedimentary rock or igneous rock. Discuss these
- ptions with a partner and then click on the pictures to see if these
rocks are the source of fossils. Igneous Rock Sedimentary Rock Igneous rock forms as hot magma cools. Any
- rganism that is covered in
hot magma would not survive the heat. Fossils do not form in igneous rock. Sedimentary rock forms when layers
- f soft sediment harden into rock.
This is how fossils form.
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Sediments flow on top of each other and slowly harden to rock. Then, more sediment flows on top of the rock, eventually turning into more rock. This creates layers of rock where fossils can be preserved. Look at the sedimentary rock below. Which fossil was created earlier: fossil A or fossil B? A B
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A B Fossil B would have formed first. After the sediment surrounding B hardened, more sediment piled on top where fossil A would have eventually formed.
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Click the image below to watch a video about fossils. Watch closely - can you find an imprint, a preserved fossil and a mineralized fossil in the video?