Four laws or principles are involved with the study of stratigraphy. They are?

The four key laws or principles of stratigraphy are the Law of Superposition, which states that in undisturbed layers of rock, older layers are at the bottom and younger ones at the top; the Principle of Original Horizontality, which posits that layers of sediment are originally deposited horizontally; the Principle of Lateral Continuity, which asserts that layers extend laterally until they thin out or encounter a barrier; and the Principle of Cross-Cutting Relationships, which indicates that a geological feature that cuts through another is younger than the feature it disrupts. These principles help geologists interpret the geological history of an area.