Question

Explain how water erosion by groundwater can form a cave.

Answer 1

Groundwater can cause erosion through chemical weathering. First, water that sinks into the ground mixes with carbon dioxide to form carbonic acid, a weak acid. Carbonic acid can break down limestone. Some of the limestone changes chemically and is carried away in a solution of water. This gradually hollows out pockets in the rock. Over time, these pockets develop into large holes underground—caves or caverns.

Step-by-step explanation:

Answer 2

Rainwater picks up carbon dioxide from the air and as it percolates through the soil, which turns into a weak acid. This slowly dissolves out the limestone along the joints, bedding planes and fractures, some of which become enlarged enough to form caves.