Question: Which image is an example of an angular unconformity?

Answer: sedimentary rock 6, shaped like a triangle

Question: In the images below, which contains a disconformity?

Answer: Sedimentary rock 3/Sedimentary rock 2~~~~Sedimentary rock 1

Question: What does the term unconformity mean?

Answer: a missing rock layer in a sequence that represents a period of erosion or nondeposition

Question: In the following rock sequence, how much erosion might have occurred between rock layer A and rock layer B?

Answer: none or only a very small amount (Time does not equate to erosion.)

Question: What characteristic most directly DISTINGUISHES an angular unconformity from a nonconformity?

Answer: Angular unconformities separate rock layers along nonparallel surfaces.

Question: Which list best describes the events that would lead to the layering of sedimentary rocks in this diagram?

Answer: deposition, erosion, deposition, erosion, deposition

Question: What happens during radioactive decay?

Answer: Parent isotopes turn into daughter isotopes.

Question: What is the scientific definition of half-life?

Answer: the amount of time over which the number of parent isotopes decreases by half

Question: Two containers hold the same radioactive isotope. Container A contains 1000 atoms, and container B contains 500 atoms. Which of the following statements about containers A and B is true?

Answer: