Determination of distance and location using instruments receiving signals from the Global Positioning System, a system of satellites for identifying earth locations.
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.
Homepage for the Southern California Integrated GPS Network (SCIGN) Pasadena Field Office involved in operating GPS stations, data recording, and supplying of earthquake data. Links to GPS data analysis, photos, and technical information.
Short descriptions and links to further information on projects using digital image processing, remote sensing, GIS and GPS technologies at the Columbia Environmental Research Center (CERC) in Missouri for biology and geomorphology research.
Results of ground-surface monitoring and borehole water table measurements document subsidence of the land surface correlative with changes in the ground water.
Online report for an interactive workshop Impact of Climate Change and Land Use in the Southwestern United States. Discusses land subsidence due to increased ground water pumping in the Southwest and the damage caused by subsidence.
Report on the Sirenia Project use of a radio tracking study to determine manatee movement patterns and habitat to develop ecological models to understand and predict the effects of hydrologic restoration on manatees in Southwest Florida.
Explanation of uplift in the land surface of the northern part of the Yellowstone caldera (12cm, about ~5 inches) that occurred between 1997 and 2003, including the scientific methods by which it was detected and analyzed.
Overview of the Long Valley Caldera with links to monitoring data including earthquakes and deformations, long-term outlook, volcano hazards in the area, USGS response plan, image gallery, monitoring and topical studies, publications and references.
U.S. Department of the Interior |
U.S. Geological Survey