As water flows through a limestone, some of the rock dissolves. This process can lead to the formation of cavities and caves. If a cave becomes too large and unstable to support the overbearing rock, it will collapse, leaving a sink hole at the surface.
It is called a karst landscape.
Karst geologic structures (limestone and sandstone layers) make the surface overlying them, too unstable for most human applications (tall buildings, urban development, major highways, bridges, etc.). Husbanding of grazing animals (horses, cows, sheep, etc) is compatible with this landscape. Sink holes, underground and disappearing streams, limestone, sandstone, and caves with their inevitable sink holes are typical of the Karst topographies.
If you mean a sink hole, then its calcium carbonate (CaCO3) ie limestone.
If it's an outlet that's round with many holes it is probably the drain in the sink.
Formations are created through many different types of processes . In addition to being dissolved by slightly acidic water, carbonate rocks are eroded by weathering due to rain fall and wind. Even gravity will have an affect on creating sinks or sink holes.
Dissolution features such as dolines and sink holes as well as caves are common when limestone wihin the earth is dissolved.
Limestone
It is called a karst landscape.
Is Georgia proneto sink holes
The ocean. Limestone.
sink holes are destuctive because it is breaking down the earth surface
Karst geologic structures (limestone and sandstone layers) make the surface overlying them, too unstable for most human applications (tall buildings, urban development, major highways, bridges, etc.). Husbanding of grazing animals (horses, cows, sheep, etc) is compatible with this landscape. Sink holes, underground and disappearing streams, limestone, sandstone, and caves with their inevitable sink holes are typical of the Karst topographies.
Regions overlying limestone bedrock tend to have fewer visible groundwater sources (such as streams & ponds), since surface water easily drains downward through permeable fractures and fissures in the limestone
Dissolution features such as dolines and sink holes as well as caves are common when limestone wihin the earth is dissolved.
If you are referring to sink holes, they form when groundwater makes the ground unstable and it collapses.
Sink holes can form in a glacial moraine, when an entombed mass of ice melts, leaving a cavity, which eventually makes its way to the surface by progressive collapse. In a landscape with underlying limestone, gradual dissolution of the limestone can lead to a collapse of the ground surface.
the people who put the pool there and didn't check for sink holes