I did find out that I was using incomplete data. I am working with a new set of data and it's all very interesting. On the graph where we saw the big spike in the early eighties, this showed just over 300 quakes, complete data shows there were over 1,200 quakes in a single month.

Also I have found that since 1960 and within a 15km radius of Obsidian Butte there has been nearly 9,000 earthquakes. Of those (not counting yesterdays quakes), only 18 have been 4.0 or greater. Only two above 5, with the largest being a 5.8.

Feel free to visit my blog for my new report. -Brad

• West Coast Earthquakes