<p><b>The appearance of a massive sinkhole in <a href="http://maps.nationalgeographic.com/map-machine#s=r&amp;c=14.631399785242074, -90.52390985190868&amp;z=11">Guatemala City (map)</a>, <a href="http://travel.nationalgeographic.com/travel/countries/guatemala-guide/">Guatemala</a>, on Sunday is thought to have been triggered by tropical storm Agatha, a violent tempest that struck Central America over the weekend.</b></p> <p>From photographs, the new Guatemala <a href="http://www.nationalgeographic.com/environment/sinkhole/">sinkhole</a> appears to be about 60 feet (18 meters) wide and about 300 feet (100 meters) deep, said <a href="http://www.uky.edu/KGS/about/biographies/currensbio.htm">James Currens</a>, a hydrogeologist at the University of Kentucky—which explains how the sinkhole was reportedly able to swallow an entire three-story building.</p> <p>Sinkholes can form when water-saturated soil and other particles become too heavy and cause the roofs of existing voids in the soil to collapse, Currens said.</p> <p>Another way sinkholes can form is if water enlarges a natural fracture in a limestone bedrock layer. As the crack gets bigger, the topsoil gently slumps and develops into a sinkhole.</p> <p>In either case, the final collapse can be sudden, Currens said.<i></i></p> <p><i>—Ker Than</i></p>