Exploring Recent Earthquakes

Go to the World Data Center for Seismology at http://neic.usgs.gov/. Click on "Current earthquake information" then choose "Current earthquake maps" (the second item in the list) to see the location of recent earthquakes.

1. Where was the largest earthquake in the world in the past month? Where was the most recent one? Click on the map location of the most recent earthquake, and record the following information: When did it occur? Where was it exactly? How deep was it? What was its magnitude?

2. One of the largest earthquakes in recent years was one of magnitude 8.4 off the coast of South America in 2001. Where and when did this occur? How much damage did it cause? Why was the damage less than it otherwise might have been? Hint: Look first for "Large/Significant Earthquakes" by year at http://neic.usgs.gov/current_seismicity.html, then click on 2001 to find the largest. A brief summary is presented under "Large/Noteworthy Earthquakes in 2001." A more detailed analysis is given under "Significant Earthquakes of the World in 2001."

For another view of recent earthquakes, go to www.crustal.ucsb.edu/ics/ understanding/ and click on the rotating globe. If you have a broadband connection, increase the speed of rotation to get a smoother motion. Does information given on this page agree with your answer to question 1 above?

Understanding Volcanoes

USGS Hawaii Volcano Observatory is one of the most important places for studying and understanding volcanoes. Visit the observatory’s website at http://hvo.wr.usgs.gov/

1. Which of the volcanoes discussed at this website is the largest in the world? Which is the most active?

2. Why are earthquakes discussed on this volcano website?

3. What are the major hazards to people from these volcanoes?

For a good collection of volcano images, go to the USGS Cascades Volcano Observatory at http://vulcan.wr.usgs.gov/Photo/framework.html

The Natural Resources Conservation Service (NRCS), part of the U.S. Department of Agriculture, is the agency that monitors agricultural resources and conditions. Among its data-gathering efforts, the NRCS produces a Natural Resources Inventory (NRI), with maps of farmland conditions across the mainland United States. Visit the NRCS/NRI website at www.nrcs.usda.gov/technical/land/erosion.html

Find the list of erosion maps. Look at several of the maps. First identify the meaning of the colors. Then identify the major concentration of high and low erosion rates.

1. Where is wind erosion worst? Where is water erosion worst?

2. Where are the most acres of highly erodible cropland? What kind of physical features might occur there?