Question

This phenomenon underwent a change 784,000 years ago named for Bernard Brunhes and Motonori Matuyama. Bauer plots compare this phenomenon’s dip angle with its declination, which is zero on agonic (“ay-gonic”) lines. Changes in this phenomenon’s orientation delineate chrons. This phenomenon’s strength reaches a minimum at the South Atlantic Anomaly, where the van Allen belts are closest to the surface. Dynamo theory posits this phenomenon is produced by the convection of iron and nickel. The interaction (10[1])of solar wind with this phenomenon forms aurorae. For 10 points, the Earth’s core produces what phenomenon that makes compasses point north? ■END■

ANSWER: geomagnetic field [or the Earth’s magnetic field or Earth’s magnetosphere or equivalents; prompt on magnetic field or magnetosphere with “of what body?”; prompt on geomagnetic reversal with “which involves what entity?”]
<Other Science>
= Average correct buzz position

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Buzzes

PlayerTeamOpponentBuzz PositionValue
Justin QianUBC BUBC A7410

Summary

2024 ACF Fall at Ohio StatefallY250%0%50%29.00
2024 ACF Fall at WashingtonfallY1100%0%0%74.00
2024 ACF Fall at GeorgiafallY1100%0%100%97.00
2024 ACF Fall at North CarolinafallY3100%0%33%79.33
2024 ACF Fall at IllinoisfallY10100%0%30%72.70