supported by the National Natural Science Foundation of China(Grant No.40272059);the Preresearch Project of the National Basic Research Priorities Prugram(Grant No.2001CCA01800)
^(87)Sr/^(86)Sr ratios of marine carbonate samples collected from a sedimentary section of the Late Cretaceous in the south of Tibet were measured.Based on the absence of cathodoluminescence and a very low Mn/Sr ratio...