NR-1 Sinkhole NR-1 Sinkhole The NR-1 Sinkhole is a giant underwater sinkhole located in the Straits of Florida southwest of Key West, Florida. It is found at an approximate depth of of water at the foot of the Pourtales Escarpment, an area of Quaternary sediment. It was discovered in October 1994 during a survey conducted by the American submarine NR-1, a U.S. Navy nuclear research submarine, and is named for the submarine. It was first identified via side-scan sonar and near-bottom echo sounder data, prompting a second survey in May 1995 to confirm the finding. Discovery of the NR-1 Sinkhole prompted scientific
2010 Guatemala City sinkhole Guatemala City. The hazards around the pipe have since then been mitigated, by improved handling of the city's wastewater and runoff. Several rainstorms also contributed to the sinkhole's collapse, as stormwater percolated into the ground, further dissolving the rocks beneath Guatemala City. The 2010 sinkhole was formed for similar reasons. The sinkhole formed due to volcanic pumice deposits, upon which Guatemala City is built. These deposits were unconsolidated and of low density, allowing easy erosion. According to Sam Bonis, a geologist at Dartmouth College, leaking pipes went unfixed long enough to create the conditions necessary for sinkhole formation because of