Which of the following best describes an “unconformity”?
A fault or fracture with younger strata above and older strata below.
B. A surface of erosion with younger strata above and older strata below.
C. A surface of erosion with older strata above and younger strata below.
D. A fault or fracture with older strata above and younger strata below.
Relative time answers which one is older and which one is younger. The simple rules or principles we usually used are:
A. Principle of Original Horizontality
B. Law of Superposition
C. Principle of Cross-Cutting Relationships
D. Principle of lateral continuity
E. Faunal Succession
F. Inclusions and Cross-Cutting Relations
Inclusions and cross-Cutting relations tell us that the younger broke the old.
The statement "The present is the key to the past" is referred as：
A. Uniformitarianism
B. Catastrophism
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