Hi Chris - I don't trust the map for numbers - There are quake reports on Trinet that Kate Hutton updates - every Thursday they post the number of quakes recorded and located for the Southern Cal region - they also provide a summary and map. Northern Cal generates weekly reports that report numbers of quakes above a certain magnitude for different areas.

The link below will take you to both sets of reports.

For instance, Southern cal shows:
17:29 PDT Thursday, May 08 - We have recorded and located 153 earthquakes in the last week.
17:15 PDT Thursday, May 01 - We have recorded and located 171 earthquakes in the last week.

Northern Cal numbers are: 45 for week ending May 8 and 50 for week ending May 1.

I have a data set that includes these weekly numbers for southern cal from July 2001 thru Sept 2002 - I haven't updated it since september - the average for that period was 285 per week but there were some coso swarms, anza area swarm and calexico swarms - if you remove the swarm type activity its around 200 a week..There's a chart of the data posted on Earthwaves somewhere....

The least number of quakes in that data set is 45 for Aprill 18, 2002 - The most was 1458 for a coso swarm in July 2001

This week's 153 is the third lowest number in that period. I don't know if any of this is meaningful....
Canie

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