In karst landscapes, which process forms caves through the dissolution of rocks by groundwater?

In karst landscapes, which process forms caves through the dissolution of rocks by groundwater?

• A. By physical abrasion of rocks by wind.
• B. By tectonic uplift exposing rocks to surface conditions.
• C. By chemical erosion from acid rain only.
• D. By dissolution of soluble rocks by mildly acidic groundwater.

Answer: (D)

In karst landscapes, caves form through chemical weathering driven by groundwater chemistry. Water that has absorbed carbon dioxide from the air and soil becomes mildly acidic (carbonic acid). This acid reacts with soluble rocks like limestone, dissolving calcite and slowly widening fractures into caves over long times. Physical abrasion from wind or uplift exposing rocks doesn’t create these caves, and acid rain alone isn’t the ongoing mechanism; it’s the persistent action of mildly acidic groundwater that carves out cavities. So dissolution of soluble rocks by mildly acidic groundwater best explains cave formation in karst terrain.

In karst landscapes, caves form through chemical weathering driven by groundwater chemistry. Water that has absorbed carbon dioxide from the air and soil becomes mildly acidic (carbonic acid). This acid reacts with soluble rocks like limestone, dissolving calcite and slowly widening fractures into caves over long times. Physical abrasion from wind or uplift exposing rocks doesn’t create these caves, and acid rain alone isn’t the ongoing mechanism; it’s the persistent action of mildly acidic groundwater that carves out cavities. So dissolution of soluble rocks by mildly acidic groundwater best explains cave formation in karst terrain.