How Are Volcanoes Related to Plate Tectonics?
ES0901  Volcanoes in the Northwestern United States

Both Hawaii and Alaska have active volcanoes. In the rest of the United States however, volcanic activity is observed only in the Pacific Northwest. In this investigation, you’ll plot volcano locations and explore how volcanism is related to plate tectonics.

  !   Read the text and follow the instructions below on the left.

 

 
   

 

 

1. Were your predictions for plate boundary locations close? What clues did you use to make your most accurate predictions?

2. Sketch the location of volcanoes and plate boundaries onto the map on your answer sheet.

3. Why do you think volcanism on the seafloor occurs directly along a plate boundary, but the Cascade volcanoes occur along a line at some distance from the plate boundary?

 
   

 Step:   1   2   3   4