Question

In which situation is the principle of cross-cutting relationships useful in determining relative age?

A fault breaks through sedimentary layers.
Fossils of two different species are found in different rock layers.
Sedimentary layers form over millions of years in a lake bottom.
Lava flows form on top of one another from several eruptions over time.

Answer 1

A fault breaks through sedimentary layers.

Explanation: The principle of cross-cutting relationships says a geologic feature (like a fault or an intrusion) that cuts across other rocks is younger than the rocks it cuts. The other choices relate to fossil succession or superposition, not cross-cutting.