Sinkhole is a natural depression or hole in the Earth's surface caused by karst processes the chemical dissolution of carbonate rocks or suffosion processes in sandstone.
It’s happened in limestone area or in the ground which have a crack in the below, so that water can go in easily. Sinkhole usually is happened in non-human area , but sometimes it’s happened in the crowded human area (like in Guatemala).
Guatemala's Sinkhole Picture
Guatemala's Sinkhole Video
Sinkhole is happened from some parts. In the beginning, there is a crack and make a big hole and water will go in. It’s usually happened in limestone area because limestone area is relative more dissolved than other stone. After that will shaped a cavity and then it will filled by water. This water at last will scratch soil so that it come to the underground and the soil will go down. Except that, the river in underground also can shaped a cavity because happened erosion there.
This process is happened continuously and the last the hole make a big space in the ground so the soil in the top can not to hold it. The hole is not up to the lowest part because the topstone is not gone totality. The depth of the hole is from several meters until 600 meters.
To know possibility of the sinkhole, we can see from the sign. First, sinkhole is happened in the area where the bedrock is limestone.
Second, it’s usually happened the change of hydrology system. Third, we will find some cracks in the ground.
If someone want to drill the ground to get water sources, they must check the soil condition. Are there any hole? Are there any hydrology changed which is seen in some periods of the season?
They are needed to prevent the
source :http://www.dailymail.co.uk/news/article-1286026/Driver-lucky-escape-sinkhole-swallows-car-busy-China-motorway.html
