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晚麦斯特里希特阶—早达宁阶高分辨的海水~(87)Sr/~(86)Sr 参考曲线是根据两个白垩纪-第三纪界线(K-T 界线)(法国的 Bidart 和突尼斯的 E1 Kef)剖面建立的。~(87)Sr/~(86)Sr 比率曲线表明,在 K-T 界线前0.3～0.4Ma 和 K-T 界线处其值最大。第一个最大值代表 Deccan Traps 火山活动主喷出期的开始。第二个最大值是一个快速的0.00006~(87)Sr/~(86)Sr 变化,变化范围从 K-T 界线下3～4m 到 K-T 界线上1m。这个剖面由 K-T 界线原来尖锐的~(87)Sr/~(86)Sr 异常曲线通过成岩作用圆滑,而不是一个渐变的过程。这种突变可能是由以下几种因素引起的:(1)Chicxulub 撞击岩的蒸发作用;(2)全球野火;(3)土壤及硅铝质岩石的酸雨淋滤。这三种可能性中,只有通过伴随 K-T 事件增加雨量的土壤淋滤产生的 Sr 释出对产生可以观察到的 K-T ~(87)Sr/~(86)Sr 异常才是重要的。
The Late Marist-Early Darlingian high-resolution seawater 87 Sr / ~ (86) Sr reference curve is based on two Cretaceous-Tertiary boundaries (KT boundary) (Bidart, France Tunisian E1 Kef) section established. The curve of ~ (87) Sr / ~ (86) Sr shows that it has the largest value at the boundary of 0.3 ~ 0.4Ma and K-T in front of the K-T boundary. The first maximum represents the beginning of the main eruption of the Deccan Traps volcano. The second maximum is a fast 0.00006 ~ (87) Sr / ~ (86) Sr variation ranging from 3 ~ 4m below the K-T boundary to 1m above the K-T boundary. The profile is smooth rather than a gradual change through diagenesis by the sharp 87 Sr / 86 Sr anomalous curve originally from the K-T boundary. This mutation can be caused by several factors: (1) the evaporation of the Chicxulub rock; (2) the global wildfire; and (3) the acid rain leaching of soil and siliceous rocks. Of the three possibilities, only the release of Sr by soil leaching with increased rainfall with the K-T event is important for the observable K-T 87 Sr / 86 Sr failure.