The principle of stratigraphic superposition tells us that _____.
A)a rock unit is older than any geologic feature that disturbs or cuts it.
B)the oldest rock strata in any undisturbed sedimentary sequence are on the bottom,and the youngest are on the top.
C)sedimentary rock strata are deposited in flat-lying layers,one on top of another.
D)All of the above are true.

Question

Quizplus · Accepted Answer

The principle of stratigraphic superposition states that the oldest rock strata in any undisturbed sedimentary sequence are on the bottom, and the youngest are on the top. This principle is used to determine the relative ages of rock units based on their positions in a sequence of sedimentary rocks. It does not necessarily tell us anything about the orientation or depositional environment of the rocks, only their relative ages. Option A is partly correct but incomplete, as it only applies to situations where there is an obvious disturbance or cutting of the rock sequence. Option C is incorrect, as sedimentary rock strata can be deposited in a variety of orientations depending on the depositional environment.

The Principle of Stratigraphic Superposition Tells Us That _____