Repeated observation or sampling at a site, on a scheduled or event basis, for study and analysis. In general, this category excludes sampling programs in which materials are obtained in the field and brought back to a laboratory for study and analysis.
Using satellite telemetry and field studies to track pintail ducks during spring migration north from California's Central Valley plus pintails in New Mexico and Texas. Includes links to migration maps, journal, duck calls, and field methods.
With the South Carolina Department of Health and Environmental Control, USGS is drilling a deep geologic test well to learn about the regional Floridan aquifer, which provides groundwater to the Hilton Head area.
Map display that highlights states where the streamflow index at USGS streamgages, averaged statewide, were below normal for the past seven days with links to comparison of recent streamflow values with historic values.
Article in the May 28, 1998 issue of Volcano Watch describing of correlation of earth tides to volcanic eruptions and value in monitoring underground magma movement with deformation measurement instruments including tiltmeters and strainmeters.
Information on earthquake activity, earthquake science, and earthquake hazard reduction with links to news reports, products and services, educational resources for teachers, glossary, and current U.S. earthquake activity map.
Answers to a wide variety of questions (FAQs) about earthquakes, such as dictionary of terms, earthquake activity and probabilities, common myths, faults, plate tectonics, and earthquake measurement techniques.