Detection and measurement of land subsidence using Global Positioning System surveying and interferometric synthetic aperture radar, Coachella Valley, California, 1996-2005

http://pubs.usgs.gov/sir/2007/5251/

Detailed measurements of elevation help to understand the extent and severity of subsidence. Study asks if subsidence indicates the aquifer system is compacting temporarily or permanently, and are the changes human-induced or tectonic.

by Sneed, Michelle and Brandt, Justin T.

U.S. Geological Survey Scientific Investigations Report 2007-5251