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A topographic map of an area in Florida shows numerous depressions in the ground?

The bedrock in the area is limestone, Describe two ways in which the depressions may have been formed?

Public Comments

1. Sink holes and mining
2. Florida is very low elevation The water level in the ground rises and falls not far below the surface. When small cracks and fissures occur in limestone and the level drops, carbon dioxide from the air dissolves in the water and the acid formed etches away the limestone, making the passages bigger, eventually making caves that get thinner and thinner on the top as they approach the surface When the rock gets too thin, the weight of the soil and rock causes the roof of the cave to collapse making a "sink hole" in the ground which is often round because of the way the rock erodes from the bottom in making the cave.