I thought you might be interested in seeing a geographic configuration that has been in the news lately. According to Wikipedia, sinkholes are common where the rock below the land surface is limestone or other carbonate rock, salt beds, or rocks that can naturally be dissolved by circulating ground water. As the rock dissolves, spaces and caverns develop underground. These sinkholes can be dramatic, because the surface land usually stays intact until there is not enough support. Then, a sudden collapse of the land surface can occur. This sinkhole is found on Paynes Prairie in Gainesville, Florida, and the scene is framed with Spanish moss. I suggest you enlarge the picture so you can better see where the level of the land is depressed, it is covered with some kind of vibrant green covering. I don't know when this particular sinkhole was formed, but it must have taken a number of years for the plants to grow and cover it.
Most definitely a problem in Florida. Great illustration here! Recently a man in Brandon (near Tampa, FL) was swallowed up by a sinkhole while he was sleeping....buried alive! His home was about 30 yrs old as I recall and the site below his master bedroom collapsed in the middle of the night.
I like your framing with the Spanish moss. I heard on the news about that poor man sleeping in his own bedroom and then swallowed alive by the sinkhole. It is like something from a horror movie.
