Question

4/10
what does an
unconformity in the rock
layers indicate?
a period of uplift, weathering, erosion, and subsidence
a continuous deposition of sediments
a sudden change in rock type
a volcanic eruption

Explanation:

An unconformity represents a gap in the geologic record. This gap forms when rock layers are exposed (via uplift), eroded/weathered, then covered by new sediments after subsidence, interrupting continuous deposition. The other options do not match this definition: continuous deposition would create no gap, a sudden rock type change is not an unconformity, and volcanic eruptions form igneous rock layers, not gaps.

Answer:

A. A period of uplift, weathering, erosion, and subsidence