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The secular change in Sr-87/Sr-86 ratio of the Mesozoic recorded the highest value above 0.7083 in Early-Middle Triassic boundary, i.e., the Triassic maximum, suggesting that a major reform in oceanography occurred after the end-Permian mass extinction. We have detected correlative highest Sr-87/Sr-86 value from the Triassic carbonate, including our data. The stratigraphic horizon of the maximum was constrained to the Olenekian-Anisian boundary (OAB) (247.2 Ma), by conodont. As the oceanic data represent the global average, the present study confirmed the chemostratigraphical utility of the "Triassic maximum" of Sr-87/Sr-86 ratio in global correlation. After the sharp rise throughout Early Triassic since the end-Permian mass extinction, a remarkable turnover of seawater-Sr-87/Sr-86 values appeared in the OAB. A major global change likely appeared in the OAB to change the Sr-isotope balance in seawater from a continental flux-dominated to a mantle flux-dominated regime. The sharp turning point in Sr-87/Sr-86 values likely has recorded the timing of the biological influence on the environment.