In picture B, new rocks were introduced. What law is best explained in this kind of rock stratum?

Since new rocks were introduced in picture B, the law which best explain this kind of rock stratum is: Steno's law of superposition.

Nicolas Steno was a 17th-century Dan-ish geologist who developed the four (4) laws of stratigraphy.

Basically, these laws governing stratigraphy revealed a lot of information to humans about the formation of a rock and its layers. Also, the laws of stratigraphy describes how endogenic and exogenic geological processes give rise to alteration in rocks, thereby, leading to the formation and deformation of rock layers.

The four (4) laws of stratigraphy include the following:

Steno's law of superposition states that within a sequence of rock layers (rock strata) in sedimentary rocks, the oldest (first) strata lies at the base (bottom) of the sequence while younger (newer) strata sit atop the older strata.

Hence, the sequence of rock layers (rock strata) in sedimentary rocks typically marks the time of deposition of each of the rock layers according to Steno's law of superposition.

In conclusion, the introduction of new rocks in picture B best explains Steno's law of superposition.

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Principle of cross-cutting relationships

Explanation:

The principle introduced in this rock stratum is the principle of cross-cutting relationships.

This principle states that "in a sequence of rock strata, the feature that cuts another is younger than the rocks they permeate through".

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