Evidence for coeval Late Triassic terrestrial impacts from the Rochechouart (France) meteorite crater
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چکیده
High temperature impact melt breccias from the Rochechouart (France) meteorite crater record a magnetization component with antipodal, normal and reverse polarities. The corresponding paleomagnetic pole for this component lies between the 220 Ma and 210 Ma reference poles on the Eurasian apparent polar wander path, consistent with the 214±8 Ma Ar/Ar age of the crater. Late Triassic tectonic reconstructions of the Eurasian and North American plates place this pole within 95% confidence limits of the paleomagnetic pole from the Manicouagan (Canada) meteorite impact crater, which is dated at 214±1 Ma. Together, these observations reinforce the hypothesis of a Late Triassic, multiple meteorite impact event on Earth.
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