Weathering and erosion slowly chisel ... forming an acidic concoction that dissolves rock. For example, acid rain dissolves limestone to form karst, a type of terrain filled with fissures ...

As pollution and sulfuric acid choked North American skies in the 1970s and 80s, a bipartisan, transnational agreement spearheaded by the Environmental Protection Agency combatted acid rain, which ...

The boulders protect the limestone from chemical weathering. The depth of the limestone ... including human factors such as acid rain. The contrast between eratic and limestone beneath can act ...