首次利用气候变化特征,对由于缺少特征古生物化石资料而长期难以进行地层划分的东营凹陷南坡始新统沙河街组四段下亚段—孔店组一段的红层进行了有效划分.采用基于孢粉化石Ephedripites相对含量约束下的测井数据法恢复相对古气候变化,首先根据Ephedripites相对含量的变化确定气候变化拐点(最干旱点)的位置段,再根据能谱测井数据或常规测井数据计算出的连续粘土矿物组成确定气候拐点的具体点,即为层位界线.根据标准井测井数据建立的数学模型,可以对该井附近新钻探井的红层进行划分对比,其科学性、合理性已被之后的勘探成果所证实.该方法为缺少古生物化石数据的“哑地层”划分提供了一种新思路.%According to the characteristics of the climate change, the red beds from the Es4"1""1櫁Ekl (the Lower Sub -Member of the 4th Member, Shahejie Formation, to the 1st Member, Kongdian Formation, Eocene) in Dongying Depression are availably divided, which have not been divided for a long time because of lacking referential fossils. The relative climate change is recovered based on logging data in combination with the relative content of Ephedripites. At first, according to the relative content of Ephedripites, the depth section of the inflection point of the climate change is defined. Then, based on continuous clay mineral contents which are determined by natural gamma ray spectrometry log data or conventional log data, the concrete depth of the inflection point of the climate is thereby defined, which is recognized as the boundary in the red beds. By the model which from standard well log data, red beds in other new wells nearby can also be divided. The scientific and rational method has been proved by afterward exploration. This method provides a new thought in dividing the fossil barren-beds.
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