| The region's peculiar geology of soft limestone, called karst, has been especially troublesome. |
| These karst cavities form as conduits for water flow between input and output points. |
| Many faults have karst features developed along them, with strings of caves visible along the faults. |
| The use of caves as mortuary sites by prehistoric Native Americans was widespread in the karst region of southwest Virginia. |
| The sequence overlies Upper Triassic to Upper Cretaceous rocks and locally covers Palaeogene karst bauxite deposits. |
| Fire ants prey on karst invertebrates and the surface community food base upon which the karst species depend. |
