Before the dinosaurs, a million-year long volcanic eruption destroyed the ozone layer. Scientists concluded that the large reservoir of halogens that was stored in the Siberian lithosphere was sent into the earth's atmosphere during the volcanic explosion, effectively destroying the ozone layer

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Before the dinosaurs, a million-year long volcanic eruption destroyed the ozone layer. Scientists concluded that the large reservoir of halogens that was stored in the Siberian lithosphere was sent into the earth's atmosphere during the volcanic explosion, effectively destroying the ozone layer