A possible link between the geomagnetic field and catastrophic climate at the Paleocene-Eocene thermal maximum

摘要

We report high-precision records of a magnetic reversal event at the Paleocene-Eocene thermal maximum (PETM), a cataclysmic global warming event initiated at 55.0 Ma. This event is confirmed by both an antipodal shift in direction and a reduction in magnetic intensity during the lower and upper transitions, and it is seen at additional sites, indicating that the characteristic remanent magnetization (ChRM) was primarily acquired by Earth's magnetic field during sedimentation. This major fluctuation of Earth's magnetic field intensity is interpreted to have been linked to the PETM and to have eventually facilitated the reversal. This Paleocene-Eocene magnetic reversal (PEMR) lasted for ~53 ka, from 54.964 to 54.911 Ma, but finally recovered to an original polarity. This suggests a possible coupling between Earth's core magnetofluid dynamo sphere and the atmosphere-hydrosphere during an abrupt catastrophic climate event.