Point of Beginning

Land Subsidence in the United States

February 9, 2009

Posted By Mike Falk on 2/8/2009 at 1:28 PM

Subsidence is more common than many may realize. USGS Fact Sheet-165-00 cites several examples and causes across America.

Subsidence due to ground water pumping.




Subsidence due to sinkholes and evaporative rock.




Simpler types of vertical movement are evidenced by the age-old axiom to not place bench marks in highway side slopes.

Another thing to consider would be to ask yourself why NGS adopted the NGS 3-D Monument

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