Limestone page 2

As limestone is a permeable rock, water is able to seep down through the cracks and into the rock.

Rainwater is a weak carbonic acid which reacts with the limestone as it passes through the rock, dissolving the stone while enlarging joints and bedding planes.

On the surface the chemical weathering widens and deepens cracks to form grykes. This leaves exposed blocks of limestone called clints and the resulting pattern of blocky rock is called a limestone pavement.

Potholes and swallow holes:

Surface water and rain do not flow far on exposed limestone as they rapidly infiltrate into the rock and soil. Where a joint or intersection of joints has been greatly weathered or dissolved, water…