Geomagnetic Polarity Reversals: Can Meteor Impacts Cause Spall Disruption into the Outer Core
The conditions for spalling to occur are discussed and the possibility that meteor impacts on the Earth’s surface might cause spallation at the mantle/core boundary when the shock enters the outer core or at the inner/outer core boundary when the shock wave passes back into the outer core, having crossed the inner core, are evaluated. It is concluded that it is most unlikely that spalling will occur in the first instance and rather unlikely in the second instance. Thus, if geomagnetic polarity reversals are caused by meteor impacts, spalling is unlikely to be the mechanism by which energy of impact is transferred into the core.
KeywordsShock Wave Inner Core Acoustic Impedance Incident Shock Outer Core
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