Virtual Earthquake is an interactive web-based program designed to introduce the concepts of how an earthquake epicenter is located and how the Richter magnitude of an earthquake is determined. Virtual Earthquake shows the recordings of an earthquake's seismic waves detected by instruments far away from the earthquake. The instrument recording the seismic waves is called a seismograph and the recording ... Full description.

Students in this lesson will be introduced to the concept of tides and tidal forces. By viewing a related applet which visualizes the relationship between the Earth, moon and tides, students will gain an understanding of why the Earth experiences tides. In the process they are asked to observe and explain how the relative positions of Earth, the moon, and the sun are responsible for the moon phases, ... Full description.

Discovering Plate Boundaries is based on 5 world maps containing earthquake, volcano, topography, satellite gravity, and seafloor age data. The novel aspect of the exercise is the "jigsaw" manner in which student groups access the maps and use them to discover, classify, and describe plate boundary types. The exercise is based only on observation and description, which makes it useful at a wide variety ... Full description.

This web page explains the goals and benefits of studying gravity and magnetic data to understand subsurface geology of the Earth. It discusses uses of gravity and magnetic measurements in providing information about the density of rocks, and explains how these measurements are useful in exploration for oil and gas and mineral deposits. The page uses gravity and magnetic maps and as well as figures ... Full description.

This web site provides a short, interactive, four-question quiz on earthquakes focusing the the largest earthquake in both the world and in recent US history, preparedness, and the development of seismic instrumentation. Full description.

This on-line text offers chapters on: a Basic Description of Earthquake History, Where Earthquakes Occur, How Earthquakes Happen, Measuring Earthquakes, Volcanoes and Earthquakes, and Predicting Earthquakes. Originally published as a book in a series of general interest publications prepared by the U.S. Geological Survey. Some figures in this version of "Earthquakes", however, have been changed for ... Full description.

This collection provides a wide array of visual resources and supporting material about the December 26, 2004 Indian Ocean Tsunami. Visualizations include simple animations, satellite photographs, Quicktime animations and tsunami models. The collection also contains visualizations related to other historical tsunamis and additional resources (beyond visualizations) about tsunamis. Resources can be ... Full description.

This beginning geophysics course is designed for geology majors. It provides a relatively rigorous and homework-intensive overview of the structure and evolution of the Earth and terrestrial planets, at a level higher than a descriptive geology class, but lower than the standard introduction to geophysics for seniors or first year graduate students. Demonstrations are presented with links to a variety ... Full description.

This on-line book, published by the United States Geological Survey (USGS), covers the 1980 eruption of Mount St. Helens in Washington state. There is a discussion of the events leading up to the eruption, as well as an explanation of the mountain's volcanic history. Immediate effects are covered, including the ash falls, pyroclastic flows, and debris. Post-eruption topics include subsequent activity ... Full description.

This activity uses food to demonstrate plate tectonic motions. Students construct a model using different snacks, which represent various parts of the Earth. For example, frosting represents the asthenosphere, fruit rollups are the Earth's plates, and graham crackers are meant to be the Earth's crust. Students learn how tectonic plates (lithosphere) ride atop the slow flowing asthenosphere layer, ... Full description.