Formation

• Sink holes form, according to the science website Live Science, when supporting materials like limestone and salt beds dissolve or give way. As the surface loses its support, the weight of the ground itself pushes downward to create a sinkhole. Added weight from houses, office buildings and even cars can create additional pressure and accelerate sinkhole formation.
  
  

Warning Signs

• Attorneys for Marshall Thomas Burnett, a Florida firm that specializes in sinkhole claims, note that small cracks in a home's structure or driveway may indicate a forming sinkhole. Other signs, like separation of walls from floors and visible depressions in the lawn can also indicate an impending sinkhole.
  
  

Considerations

• Sinkholes, according to Live Science, can form suddenly and can envelop homes, vehicles and even apartment buildings. In addition, sinkholes can reach depths of tens or hundreds of feet, and they create a hazard for curious onlookers.