摘要
针对古气候量化恢复这一制约细粒沉积研究关键问题,选取干湿指数、陆源碎屑和碳酸盐3种反映古气候的指标,应用SPSS软件,提取古气候因子,建立古气候综合量化恢复方法。古气候因子越大,表明气候越暖湿,该方法在一定程度上克服了单一恢复方法的局限性,且保留了所选取几种反映古气候指标的相关信息,使古气候恢复结果更合理,具有较强的实用性。应用建立的古气候综合量化恢复方法,依据樊页1和牛页1井分析测试资料,对东营凹陷沙四段上亚段—沙三段下亚段沉积时期古气候进行恢复,并从有机质丰度、沉积构造和岩相3个方面分析古气候对细粒沉积的影响。结果表明:沙四段上亚段—沙三段下亚段沉积时期,东营凹陷古气候大致经历了干旱—半干旱期、半潮湿—潮湿期、半干旱期和半干旱—半潮湿期4个变化周期;古气候从干旱型逐渐向潮湿型过渡,垂向上形成了富有机质纹层状灰岩相—富有机质纹层状泥质云岩相—富有机质层状泥质云岩相—富有机质纹层状泥质灰岩相—富有机质纹层状灰质泥岩相—富有机质层状泥质灰岩相—富有机质层状灰质泥岩相的细粒沉积岩岩相演化序列。
Quantitative reconstruction of paleoclimate is the key to the research on fine-grained sediments.To solve this problem,three factors that can reflect the paleoclimate were proposed,which are moisture index,terrigenous clastic and car-bonate.Based on these factors,the paleoclimate indicator was extracted by SPSS,and a method for paleoclimate quantita-tive reconstruction was established.The larger the value of paleoclimate indicator,the more humid the paleoclimate.To a certain extent,this method overcomes the limitations in paleoclimate reconstruction using single method and keeps the rele-vant information of the selected factors to reflect the paleoclimate,and thus the reconstruction result is more reasonable and more practical.Using the established method,the paleoclimate was reconstructed based on data of Wells Fanye1 and Ni-uye1 in Dongying Sag during deposition of the upper Es4 and the lower Es3.Meanwhile,the effect of the paleoclimate on fine-grained sediments was studied from three aspects,including organic matter abundance,sedimentary structure and lithofacies.The results show that there are four paleoclimatic cycles during the deposition of the upper Es4 and the lower Es3 in Dongying Sag,which are arid to semi-arid,semi-humid to humid,semi-arid and semi-arid to semi-humid.The paleocli-mate changed gradually from arid to humid.As a result,a fine-grained sedimentary lithofacies evolution sequence devel?oped vertically,which are organic-rich laminated limestone lithofacies,organic-rich laminated argillaceous dolomite litho?facies,organic-rich layered argillaceous dolomite lithofacies,organic-rich laminated argillaceous limestone lithofacies,or?ganic-rich laminated lime mudstone lithofacies,organic-rich layered argillaceous limestone lithofacies and organic-rich layered lime mudstone lithofacies.
作者
杨万芹
王学军
蒋有录
张顺
王勇
朱德燕
朱德顺
YANG Wanqin;WANG Xuejun;JIANG Youlu;ZHANG Shun;WANG Yong;ZHU Deyan;ZHU Deshun(School of Geosciences,China University of Petroleum(East China),Qingdao City,Shandong Province,266580,China;Exploration and Development Research Institute,Shengli Oilfield Company,SINOPEC,Dongying City,Shandong Province,257015,China)
出处
《油气地质与采收率》
CAS
CSCD
北大核心
2018年第2期29-36,共8页
Petroleum Geology and Recovery Efficiency
基金
国家自然科学基金项目"济阳坳陷泥页岩沉积微相及微观孔隙结构"(41372107)
国家科技重大专项"济阳坳陷页岩油勘探开发目标评价"(2017ZX05049-004)
关键词
古气候
量化恢复
细粒沉积
岩相
东营凹陷
paleoclimate
quantitative reconstruction
fine-grained sediments
lithofacies
Dongying Sag
