ASBOG Practice Exam 2025 – 400 Free Practice Questions to Pass the Exam

The principle of superposition is a fundamental concept in geology, particularly regarding sedimentary rocks. It asserts that in any undisturbed sequence of sedimentary layers, the oldest layers of rock are found at the bottom, while the younger layers are deposited on top. This principle allows geologists to determine the relative ages of rock layers and the fossils contained within them, as sediments accumulate in a chronological order over time.

Understanding the sequence is essential for reconstructing geological history, as it provides insights into the environmental conditions and changes that occurred over geological time. This is critical for various applications, including resource exploration and assessing natural hazards. The other options do not align with geological practices: stating that all rocks are formed at the same time is incorrect as it contradicts the layering that the principle of superposition explains, while suggesting that the newest rocks are at the bottom or that rocks form randomly lacks grounding in geological processes.