Which limestone layer is the youngest?

The correct choice asserts that all layers are the same age, indicating a significant geological concept in stratigraphy where certain limestone layers may exhibit similar formation periods. However, in the context of Niagara Cave and the surrounding geological formations, it is more accurate to say that these layers are not all the same age.

Each limestone layer, such as the Prosser Layer, Dubuque Layer, and Stewartville Layer, was formed during different geological periods, which implies that they possess distinct characteristics and ages due to variations in sedimentation, environmental conditions, and other geological processes throughout history. In fact, the Prosser Layer is typically younger than the others, reflecting the natural progression of geological time.

Understanding the age differences amongst these layers is crucial for visitors to appreciate the geological history and the development of the cave systems, which have unique formations, ecosystems, and histories tied to the age of the rocks comprising them. Thus, recognizing that each layer is distinct is essential for grasping the complexities of the cave's geology.