Question

3. According to the Law of Superposition, in undisturbed, horizontal, sedimentary rock layers, the oldest layer is at the bottom. Each higher layer is younger than the rocks below it. Why is it important that the rock layers be undisturbed? SC.7.E.6.3

A. If the rock layers are disturbed, the absolute age of the rocks will change
B. If the rock layers are disturbed, certain layers may be missing or relocated
C. If the rock layers are disturbed, the Law of Superposition is proven wrong
Please explain why you chose this

Answer 1

Answer: law of superposition, a major principle of stratigraphy stating that within a sequence of layers of sedimentary rock, the oldest layer is at the base and that the layers are progressively younger with ascending order in the sequence. On occasion, however, deformation may have caused the rocks of the crust to tilt, perhaps to the point of overturning them. Moreover, if erosion has blurred the record by removing substantial portions of the deformed sedimentary rock, it may not be at all clear which edge of a given layer is the original top and which is the original bottom.

law of superposition, a major principle of stratigraphy stating that within a sequence of layers of sedimentary rock, the oldest layer is at the base and that the layers are progressively younger with ascending order in the sequence.