Acquiring information about a natural feature or phenomenon, such as the Earth's surface, without actually being in contact with it. USGS remote sensing is usually carried out with airborne or spaceborne sensors or cameras.
Information on earthquakes in central California and the San Francisco region with links to four types of field studies, deep seismic investigations, geotechnical investigations, shallow seismic imaging, and airborne geophysical surveys.
USGS responses to and studies of the hazards and impact of major hurricanes, tsunamis, and El Nino storms. Includes links to oblique aerial photography and LIDAR surveys recording coastal changes and other effects of storms and waves.
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.