There are several hypotheses for the causes of these extinctions. There is evidence that major changes in the carbon cycle  and sea level occurred during this time . Evidence also exists for the development of anoxia (a loss of oxygen) in some environments in the oceans .
One hypothesis that unifies this evidence links these environmental changes to widespread volcanic eruptions caused by the emplacement of the Kalkarindji Large Igneous Province or LIP . These widespread eruptions would have injected large amounts of greenhouse gases into the atmosphere causing warming of the climate and subsequent acidification and loss of oxygen in the oceans . However the precise timing between the eruptions and the extinction events remain unresolved .
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