The most widespread type of masonry work is the erection of solid brick masonry using individual bricks set in mortar. âLight masonry,â consisting of two parallel face walls each one-half a brick thick and filled with a light concrete, loose slag, or another insulating material, is sometimes used.
A sinkhole, also known as a cenote, sink, sink-hole, shakehole, swallet, swallow hole, or doline (the different terms for sinkholes are often used interchangeably), is a depression or hole in the ground caused by some form of collapse of the surface layer.
According to the US Geological Survey, sinkholes are common where the rock below the surface is limestone, carbonate rock, salt beds, or other kinds of rock which can naturally be dissolved by groundwater circulating through them. As the rock dissolves, spaces and caverns develop underground.econdly, there are cover-subsidence sinkholes, which form slowly over time with the ground gradually subsiding or deflating. These types of events can be less noticeable and go undetected for long periods. Sinkhole collapses can range in size and severity.