What is stratigraphy?

What is stratigraphy?

• A. Study of rock layers and layering.
• B. Study of earthquakes.
• C. Study of fossils.
• D. Study of volcanic activity.

Answer: (A)

Stratigraphy is the study of rock layers and layering. By looking at the order, thickness, and composition of sedimentary layers, and the fossils they contain, geologists reconstruct how environments changed over time and how different rocks relate to one another in history. The method relies on principles like layers being deposited in a sequence from oldest at the bottom to youngest at the top, layers originally being laid down horizontally, and features that cut through layers indicating a later event. This allows scientists correlate strata across different places and build a timeline of past events. The other topics—earthquakes, fossils as a broader field, and volcanic activity—are studied in related areas (seismology, paleontology, and volcanology) but do not define stratigraphy.

Stratigraphy is the study of rock layers and layering. By looking at the order, thickness, and composition of sedimentary layers, and the fossils they contain, geologists reconstruct how environments changed over time and how different rocks relate to one another in history. The method relies on principles like layers being deposited in a sequence from oldest at the bottom to youngest at the top, layers originally being laid down horizontally, and features that cut through layers indicating a later event. This allows scientists correlate strata across different places and build a timeline of past events. The other topics—earthquakes, fossils as a broader field, and volcanic activity—are studied in related areas (seismology, paleontology, and volcanology) but do not define stratigraphy.