Explanation of the Earth's gravitational field, emphasizing how USGS scientists measure gravity and portray these measurements on maps. Explains terminology of gravity anomaly maps and their relationship to the rock types and other geologic features.
Links to products of magnetic, gravity, magnetotelluric, and multi-discipline reports and surveys of regions in the U.S. and Antarctica plus geophysical software tools. Some products are in PDF format.
Airborne electromagnetic surveying is used to estimate the character of the permafrost by measuring and monitoring the electrical resistivity, which is affected by lithology, temperature, water, and ice.
Project summary, photos of logging truck, and bibliographies on log interpretation techniques and instrumentation to record geophysical data in wells and test holes for studying ground water hydraulics and evaluate waste disposal sites.
Coordinated studies of the effect of historical mining for mercury, origin and composition of metals in groundwaters and surface waters, history of volcanic and intrusive activity, and the complex geological history of this area.
This publication (Open-File Report 95-479) is a teacher's guide to two U.S. Geological Survey maps that show gravity and magnetic data in contour form superimposed on a LANDSAT satellite image of the San Francisco Bay area.
A method to create qualitative images of thick oil in oil spills on water using near-infrared imaging spectroscopy data. It relies on the organic absorption features of chemical bonds in aliphatic hydrocarbons. The data cannot give oil volume estimates.
A program of studies with instruments to provide accurate and timely data and information on seismic events, including their effects on buildings and structures, employing modern monitoring methods and technologies.
The USGS Seismological Laboratory in Albuquerque installs and maintains a world network of seismograph stations, collects the seismic data, and evaluates seismic instruments. Site includes links to ASL publications, earthquake maps and seismic data.
Complex report on the interpretation of aeromagnetic data to study hydrogeology of the San Pedro basin, Cochise County, Arizona determining geologic structure, basin fill and depth to water. Online version of a CD-ROM publication.
This site is designed to provide information on federal interagency and cooperative developments related to coastal sand and gravel resources and management issues along the Atlantic continental margin.
Summary of an investigation of the Cascadia subduction zone with detailed density-modeling experiments of the crust and mantle along two transects across Vancouver Island and the Canadian margin and the other on the margin of central Oregon.
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.
Access to InfoBank, an online data catalog, to browse or retrieve coastal and marine geology program information, images, and data on gravity, bathymetry, seismic activity, magnetics, samples, facilities, cruises and equipment.
Overview of fractured rock research aimed at understanding the movement of water through fracture networks, and characterize field conditions influencing contaminant migration. Includes programs and publications.
Crustal imaging and characterization home with links to projects on earth science technologies including geophysical, geochemical, and isotope studies, online publications and data, and newsletter Minerals News.
Provides links to explanatory materials for the layperson, including information on concepts behind earthquake maps, the use of probability, what the maps mean, how they are made, and answers to frequently asked questions.
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.
Place to provide information about ground shaking associated with significant earthquakes. A questionnaire to let us know what you felt following an earthquake in the United States or in other countries.
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.