Hey, it's a learning process right?

I'm seeing some interesting stuff with regards to a Parkfield 2.5 during the past week and their magnetomoters. Differential Magnetic Field spikes occured at HGGD, AGGD, GRAG, and HGTF. Strangley enough nothing showed on VRTF. I noticed something similar last September when an EQ occured also. Now that I'm seeing it again I'm getting really curious. What research have you done with regards to Parkfield Mags?

Michael