Has anyone investigated solar flare/CME activity coincident with reversal of the Earth's magnetic field as a mechanism for Mass Extinction in Earth's history?
If you were to have heavy solar activity during a period when the Earth's magnetic filed were changing polarity, I'd think there'd be a period of vulnerabilty during which the earth's surface would be bathed in x-rays from the flares and CME's.
Would there be an detectable remnant of such X-ray activity in the gelogic column, such that we could correlate such an event chronologically and compare it to instances of Mass Extinctions?
Or, be I all wet?
Off-the-cuff I'd say we may be able to correlate terrestrial fission tracks and the relative abundance of noble gases with paleomagnetic data, similar to work done on chondrites. Here are some interesting links:
Two-Stage Model of Protoplanetary Irradiation