Relationship between composition and lamination structure of fine-grained sedimentary rocks in upper fourth member to lower third member of Shahejie Formation in Niuzhuang Depression
The development of laminations in lacustrine fine-grained sedimentary rocks exhibits significant variability in terms of thickness,density,and lateral continuity,which are closely related to the sedimentary environment of the fine-grained sedimentary rocks.This study focuses on the quantitative characterization of laminations thickness,density,and lateral conti-nuity in the upper fourth member to lower third member of the Shahejie Formation in Niuzhuang Depression,emplying image analysis.The findings are compared with the diverse material compositions of the fine-grained sedimentary rocks.The results indicate that there is generally no discernible correlation between the thickness,density,and lateral continuity of laminations in the specified formations and the mass fraction of quartz,clay,carbonate,and other minerals within the fine-grained sedi-mentary rocks.However,a positive correlation is observed between lamination density and organic carbon content,along with a significant positive correlation between quartz minerals and clay minerals.This suggests that a lower the sedimentation rate in the fine-grained sedimentary rocks of the studied formations facilitates an increase in organic carbon content.The transpor-tation of quartz minerals and clay minerals to deep lake environments primarily occurs through floods in the form of surface flow and interflow.The generation and precipitation of surface lake carbonate minerals appear to be independent of water depth or sedimentation rate.Furthermore,no compensation interface for lacustrine carbonate(CCD)is identified.
国家科技期刊平台
NSTL
万方数据
维普
