The geologic time scale was a relative time scale before dates were assigned to the different eras, epochs, and periods. How did geologists first determine this relative time scale? In this discussion you are going to be the geologist and determine which principles of relative dating you could use to figure out the relative age of a rock layer.
Instructions
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Use the reading (and your imagination!) to answer the primary question in an initial post of at least 150 words: How do geologists use the principles of relative dating to learn about the past?
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On a voyage to a fictitious planet, you find a sequence of five rock layers. As you study the layers more closely, you find a rock layer with alien life in it! Your fictitious rock layer must have at least three of the following characteristics: tilting, life in layers above and/or below, faulting, and inclusions. Describe your rock’s setting with at least the following information:
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Are the layers flat or tilted?
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Is there life in the layers below your rock? Above?
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Does a fault cut through your rock layer?
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Does your rock layer contain inclusions from another layer?
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Explain which relative dating principles could be combined to determine the relative age of your rock layer and how each of the principles you’ve chosen can be applied to your rock layer.
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