Introduction to Virginia’s Karst
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Transcript of Introduction to Virginia’s Karst
INTRODUCTION TO VIRGINIA’S KARST Caves, Sinkholes, and Carbonates, Oh My!
Karst-Develops in Carbonate Rocks
Carbonic Acid= CO2 + H2O
Caves and Caverns• Formed from the chemical weathering of limestone and
dolomite through carbonic acid. Cracks open and eventually widen to make a cave.
• Dripstone: Calcium carbonate deposited from solution as water enters a cave. Stalactites, Stalagmites, and Columns are all dripstones.
• Stalactites: Hang “tight” to the ceiling.• Stalagmites: Push (mightily) hard through the ground.• Column: Formed when stalactites and stalagmites meet.
Stalactites and Stalagmites
Columns
Sinkholes• Caused by the collapse of cave or cavern roof. Usually
from pumping more groundwater than can be recharged.•
Sinking Streams• Where a river or stream enters a cave system and
appears to “sink” into the ground.