Because there is a lack of fossil and chronologic data, the stratigraphic division is still disputed.

特别是由于缺乏化石及年代学资料，对研究基础的地层划分方案也一直存在争议。

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Because there is a lack of fossil and chronologic data, the stratigraphic division is still disputed.

特别是由于缺乏化石及年代学资料，对研究基础的地层划分方案也一直存在争议。

youdao