ConcepTest: Cross Section Explanation

ConcepTest questions by David McConnell , David Steer , Walter Borowski, Jeffrey Dick, Annabelle Foos, Jeffrey Knott, Alvin Konigsberg, Michelle Malone, Heidi McGrew, Kathie Owens, and Stephen Van Horn
This material was originally created for Starting Point:Introductory Geology
and is replicated here as part of the SERC Pedagogic Service.

Question:

During fieldwork in the western U.S., an experienced geologist sketched the cross section below showing three different units of tilted rocks and their relative ages. What could you best infer from this diagram?

Cross Section 1

a. Mountain building has overturned the units.
b. C formed first and so lies on the bottom.
c. B and C must be igneous rocks.
d. The sequence of rock layers conforms to the principle of superposition.

Student Responses:

No data yet. The correct response is a.

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References and Notes: