Scientists just discovered the largest cluster of sinkholes on Earth—49 in all—in northwest China. The massive natural sinkholes, all of which had been previously undiscovered, have geologists concerned about what may have caused them and how many more might occur in the future. Ongoing research continues, but early opinions suggest these sinkholes were formed over exceptionally long periods of time, and aren’t necessarily an indication of future danger.

china, sinkholes, geology, Qinling-Bashan Mountains, Hanzhong, Shaanxi Province, Chinese giant flying squirrels, red and white giant flying squirrels, rare plants, rare animals

The sinkholes were discovered during a four-month survey of a 2,000-square-mile area of the the Qinling-Bashan Mountains, which are located in the Hanzhong area of northwest China’s Shaanxi Province. Geologists tallied a cluster of 49 separate sinkholes within a 230-square-mile patch of land, and the largest of the holes measures an impressive 1,706 feet in diameter with a depth of 1,050 feet. In addition to the cluster of natural sinkholes, the study also revealed the presence of several rare plant species and Chinese giant flying squirrels.

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Upon studying the newly discovered sinkholes, the research team suggests they were most likely formed over hundreds of thousands of years. Underground water dissolves carbonate rock, such as limestone, under the surface and causes the ground to sink in upon itself. The result is an irregular but totally natural landscape that grabs the attention of scientists and cave enthusiasts alike. French cave explorer Jean Poutasi told local Chinese media that one of the formations is “the world’s most beautiful sinkhole” after a close inspection.

Via NatGeo

Images via China Daily