Exercise
Unconformities and Geological Gaps
Learn how unconformities represent missing time and gaps in the rock record caused by erosion or non-deposition.
Questions
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MultiChoice
What is an unconformity in geology?
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MultiChoice
Which type of unconformity features parallel sedimentary layers separated by an eroded surface?
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MultiChoice
An angular unconformity is identified when:
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MultiChoice
What is a nonconformity?
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MultiChoice
Which natural processes are primarily responsible for creating unconformities?
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MultiChoice
What does an unconformity represent in Earth's geological history?
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MultiChoice
Why might a expected rock layer from a specific time period be missing between two strata?
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MultiChoice
Which field observation provides direct evidence of an angular unconformity?
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MultiChoice
In forming an angular unconformity, what step must happen after horizontal layers are deposited?
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MultiChoice
How do geologists detect a disconformity when layers above and below are parallel?
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MultiChoice
If a rock layer dated at 200 million years sits directly below a layer dated at 50 million years, what is present?
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MultiChoice
Why must geologists identify unconformities when constructing geological histories?