This site offers the online version of a book published by the United States Geological Survey (USGS). It is intended to provide a brief introduction to the concept of plate tectonics, highlighting some of the people and discoveries that advanced the development of the theory. It is the companion volume to the map, 'This Dynamic Planet', which shows the locations of major volcanic belts, fault systems, ... Full description.

This website provides an overview of the San Andreas Fault Observatory at Depth (SAFOD) project, an initiative to drill into the fault in one of its most predictively active segments near Parkfield, California. Information accessible at the site includes a discussion of drilling methods, an introduction to the structure of the fault zone as it appears at Parkfield, and a discussion of earthquake prediction. ... Full description.

This set of lists and maps provides information on the latest earthquakes for the 50 states and Puerto Rico. The lists are organized by date and time, and by magnitude. On the interactive maps, symbols are coded by size (larger symbols mean greater magnitude) and by color (last hour, last day, last week). Clicking on individual map symbols links to detailed maps and written information for the selected ... Full description.

ShakeMaps, a product of the United States Geological Survey (USGS) Earthquake Hazards Program, are near-real-time maps of ground motion and shaking intensity that are produced following significant earthquakes. They appear as a set of links keyed to areas which have recently experienced an earthquake. The maps display instrumental intensity (modified Mercalli scale), peak ground acceleration, and ... Full description.

This set of lists and maps provides information on the all earthquakes occurring in the world for the past seven days. The lists are organized by date, time, and magnitude; the interactive maps are organized by region. On the maps, symbols are coded by size (larger symbols mean greater magnitude) and by color (last hour, last day, last week). Clicking on individual map symbols links to detailed maps ... Full description.

This article describes major earthquakes that have occurred in California since the colonial era, beginning with a 1769 earthquake experienced by a Spanish expedition near what is now Los Angeles, and ending with the July 1952 earthquake in Kern County. Each account provides observer's reports of injuries, fatalities, property damage, and ground effects (cracking, subsidence). More recent earthquake ... Full description.

This portion of the United States Geological Survey's (USGS) frequently-asked-questions feature on earthquakes addresses what individuals might actually experience during an earthquake. Topics include earthquake motion (rolling or shaking), earthquake effects (ground shaking, surface faulting, ground failure, etc.), earthquake magnitude, what an earthquake feels like, and others. There are also links ... Full description.

This portal provides access to a variety of resources explaining the methods used to determine the location and depth of an earthquake. The resources include the 'Travel Time Information and Calculator', an online tool that lets users choose a seismic station location and a recent earthquake, and see how long it takes different types of seismic waves to travel from the epicenter to their locations. ... Full description.

This collection of resources is intended to commemorate the centennial of the Great 1906 Earthquake that destroyed much of San Francisco. Items include maps, books and articles, photos and video, field trip ideas, interactive features, and simulations. Of particular interest is 'Putting Down Roots in Earthquake Country', a general interest publication that provides information about earthquake hazards ... Full description.

This collection of earthquake photos, published by the United States Geological Survey (USGS), contains links to photos for specific earthquakes, as well as links to other USGS image collections and non-USGS collections. Highlights include photos from the 1906 San Francisco earthquake, the 1989 Loma Prieta earthquake, and the 1994 earthquake in Northridge, California. There is also a link to the USGS ... Full description.