Start date:
Early November
End date:
Early January
Dry Valleys, Taylor Valley, Royal Society Range
Principle Investigator:
Dr Lisa Tauxe
Scripps Institution of Oceanography
The geomagnetic field is decreasing rapidly, leading some to propose that it will undergo collapse followed by a return to its usual strength but in the opposite direction, a phenomenon known as a "polarity reversal" which last happened about 800,000 years ago. Such a collapse would have a potentially devastating effect on the ability of the magnetic field to shield us from cosmic ray bombardment. The probability of such a drastic event happening depends on the average strength of the magnetic field. If the average is approximately equal to the present field, then the fact that the field is dropping rapidly would be more alarming than if the magnetic field is quite a bit higher than average, as implied by the current data for the ancient magnetic field from Antarctica. The argument over the average field strength stems from the difficulty of its estimation. To that end, researchers will re-sample ancient lava flows for which directional data are already available to explore the earth’s magnetic field strength and variation through time.