Block caving involves undermining the vertical support of the ore column, which then undergoes gravitational collapse. Ground subsidence accompanies block caving as the overlying mine roof strata bends before slowly collapsing into the growing void. The San Manuel copper mine, located about 3 miles WSW of Mammoth in the San Pedro Valley of southeastern Arizona, provides an example of the ground subsidence that accompanies block cave mining. About 0.20 square miles of surface rock collapsed into the mine.
For more, see the Arizona Geology Blog 'When the ground comes tumbling down' (10 Feb 2020).
https://blog.azgs.arizona.edu/blog/2020-02/when-ground-comes-tumbling-do...
Photographer: David Briggs
Photo Date: circa 2011
Photo Location Accuracy: Approximately Located
Photo Tags: copper mining, San Manuel, block caving, ground subsidence