Create an account
What determines if eruptions are peaceful or explosive?
Variations in magma's chemical composition, ability to flow, gas content and volume
what percent of volcanism is associated with plate boundaries?
90 - 80% spreading centers, 10% subduction zones; other 10 % at hot spots
Please allow access to your computer’s microphone to use Voice Recording.
Having trouble? Click here for help.
We can’t access your microphone!
Click the icon above to update your browser permissions and try again
Reload the page to try again!Reload
Press Cmd-0 to reset your zoom
Press Ctrl-0 to reset your zoom
It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.
Please upgrade Flash or install Chrome
to use Voice Recording.
For more help, see our troubleshooting page.
Your microphone is muted
For help fixing this issue, see this FAQ.
Star this term
You can study starred terms together