what site can I go to to read scales on earthquakes and volcanoes?

Question

Out of interest I want to learn and see live how to read a richter scale etc. I am a hands on learner and want to see how they really work. for example I want to see currently what southern California's "heart beat" is. I want to see where I can find it on the internet. Thank you! Reason: I love Geology, Volcanology, Seismology, and would love to learn how to study it by reading the scales. I want to minor and eventually switch my major to Geology.

Answer 1

Reading the seismograph is a big subject. You must know to differentiate between several forms of earthquake waves. The main waves are P wave and S waves generated from the point called focus. The L wave and R waves are surface waves generated at earth surface because of reflection and refraction. Richter scale will not give you the direct measurement of the magnitude of Richter scale. Even though I have good knowledge on earthquake and Tsunami I am not an expert in deciding the Richter scale magnitude by studying the seismograph. But the idea behind the calculation is you should find the distance of epicenter by seeing the arrival time of p wave and s wave. Roughly there will be a delay of 1 second for each 8 k/m distance. When you sense an earthquake of magnitude 3 in Richter scale at a distance of 100 k/m the shaking will be 0.1 mm. This will increase by ten fold for each Richter scale. The amplitude will get reduced by inverse square of the distance from epicenter. US GS site will provide free information on earthquakes.You can visit my site to have better knowledge on this subject.http://www.orkut.com/Community.aspx?cmm=26068261
Presentation slides
http://asia.pg.photos.yahoo.com/ph/quake

http://photos.yahoo.com/quakealert_no1

Answer 2

I'm not sure that there is any live seismic information on the web, but this would be a good place to start.
http://earthquake.usgs.gov/research/topics.php?areaID=12