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Large igneous provinces(LIPs) are considered a relevant cause for mass extinctions of marine life throughout Earth’s history.Their flood basalts and associated intrusions can cause significant release of SO_4 and CO_2 and consequently,cause major environmental disruptions.Here,we reconstruct the long-term periodic pattern of UP emplacement and its impact on ocean chemistry and biodiversity fromδ~(34)S_(sulfate) of the last 520 Ma under particular consideration of the preservation limits of UP records.A combination of cross-wavelet and other time-series analysis methods has been applied to quantify a potential chain of linkage between LIP emplacement periodicity,geochemical changes and the Phanerozoic marine genera record.We suggest a mantle plume cyclicity represented by LIP volumes(V) of V= -(350-770)×10~3 km~3 sin(2πt/ 170 Ma)+(300-650)×10~3km~3sin(2πt/64.5Ma + 2.3) for t=time in Ma.A shift from the 64.5 Ma to a weaker~28-35 Ma UP cyclicity during the Jurassic contributes together with probably independent changes in the marine sulfur cycle to less ocean anoxia,and a general stabilization of ocean chemistry and increasing marine biodiversity throughout the last~135 Ma.The UP cycle pattern is coherent with marine biodiversity fluctuations corresponding to a reduction of marine biodiversity of~120 genera/Ma at~600×10~3 km~3 LIP eruption volume.The 62-65 Ma LIP cycle pattern as well as excursion inδ~(34)S_(sulfate)and marine genera reduction suggest a not-yet identified found LIP event at~440-450 Ma.
Large igneous provinces (LIPs) are considered a relevant cause for mass extinctions of marine life throughout Earth’s history. Their flood basalts and associated intrusions can cause significant release of SO_4 and CO_2 and caused by major environmental disruptions.Here, we reconstruct the long- term periodic pattern of UP emplacement and its impact on ocean chemistry and biodiversity from δ ~ (34) S ~ (sulfate) of the last 520 Ma under particular consideration of the preservation limits of UP records. A combination of cross-wavelet and other time-series analysis methods has been applied to quantify a potential chain of linkage between LIP emplacement periodicity, geochemical changes and the Phanerozoic marine genera record. We suggest a mantle plume cyclicity represented by LIP volumes (V) of V = - (350-770) × 10 ~ 3 km ~ 3 sin (2πt / 170 Ma) + (300-650) × 10 ~ 3km ~ 3sin (2πt / 64.5Ma + 2.3) for t = time in Ma.A shift from the 64.5 Ma to a weaker ~ 28 -35 Ma UP cyclicity during the Jurassic contributes toge ther with probably independent changes in the marine sulfur cycle to less ocean anoxia, and a general stabilization of ocean chemistry and increasing marine bioenergy throughout the last ~ 135 Ma. The UP cycle pattern is coherent with marineimmune signs corresponding to a reduction of marine biodiversity of ~ 120 genera / Ma at ~ 600 × 10 ~ 3 km ~ 3 LIP eruption volume. The 62-65 Ma LIP cycle pattern as well as excursion in δ ~ (34) S and marine genera reduction suggest a not yet identified found LIP event at ~ 440-450 Ma.