柴达木盆地西部英雄岭页岩天文旋回识别与高沉积速率下的沉积充填响应特征  

Astrocycle identification and high sedimentation rates sedimentary filling response characteristics in the Yingxiongling shale of western Qaidam Basin

作　　者：盛军 薛世团 吕思锦 张彩燕 杨晓菁 李雅楠 郭笑 王转转 SHENG Jun;XUE Shituan;LYU Sijin;ZHANG Caiyan;YANG Xiaojing;LI Yanan;GUO Xiao;WANG Zhuanzhuan(Plateau Saline Lacustrine Basin Oil-Gas Geology Key Laboratory of Qinghai Province,Dunhuang Gansu 736202,China;a.Exploration&Development Research Institute,PetroChina Qinghai Oilfield Company,Dunhuang Gansu 736200,China;Oilfield Development Business Department,PetroChina Qinghai Oilfield Company,Dunhuang Gansu 736200,China;No.5 Oil Production Plant,PetroChina Qinghai Oilfield Company,Dunhuang Gansu 736200,China)

机构地区：[1]青海省高原咸化湖盆油气地质重点实验室,甘肃敦煌736202 [2]中国石油青海油田分公司勘探开发研究院,甘肃敦煌736200 [3]中国石油青海油田分公司油田开发事业部,甘肃敦煌736200 [4]中国石油青海油田分公司采油五厂,甘肃敦煌736200

出　　处：《地质科技通报》2025年第1期48-63,共16页Bulletin of Geological Science and Technology

基　　金：中国石油勘探与生产分公司科技项目“柴达木盆地页岩油综合地质研究、技术攻关与现场试验”(2022KT0304)。

摘　　要：柴达木盆地英雄岭页岩油勘探开发潜力巨大,但目前在旋回地层学方面的工作较为薄弱。为了明确英雄岭页岩的天文旋回沉积响应特征,通过对英雄岭页岩发育的下干柴沟组上段地层开展了4口井的频谱分析,综合岩心、测井、地球化学分析等方面的成果,在该套地层中识别出多组米兰科维奇旋回,并依据404.858 ka的长偏心率周期建立了英雄岭页岩“浮动”天文标尺,明确了英雄岭页岩的沉积速率与沉积充填特征。研究表明:英雄岭页岩沉积时间约为4.86 Ma、平均沉积速率达到340.44 m/Ma,高沉积速率是英雄岭页岩的重要特征之一。基于长偏心率周期分析的总有机碳含量沉积响应特征表明柴达木盆地英雄岭页岩的有机碳富集程度受沉积速率控制明显,随着沉积速率的增大,总有机碳含量呈升高趋势,当沉积速率超过450 m/Ma时,受到碎屑稀释效应影响,总有机碳含量出现显著下降。基于单一长偏心率周期的岁差旋回周期对沉积构造响应模式分析表明,当岁差参数处于最小值时,主要发育贫有机质层状灰云岩;当岁差参数处于最大值时,主要发育富有机质纹层状灰云岩。英雄岭页岩表现出的这种明显轨道强迫响应,将有助于页岩油有利层段预测,可为今后英雄岭页岩油高效勘探开发提供一些新思路。The exploration and development potential of the Yingxiongling shale oil in the Qaidam Basin is significant,however,current research on cyclostratigraphy is relatively limited.[Objective]To clarify the characteristics of the astronomical cycle sedimentary response of Yingxiong Ling shale,[Methods]This study conducts a spectral analysis of four wells in the upper section of the Lower Ganchaigou Formation,which was developed within the Yingxiongling shale.Based on the results of core analysis,logging,and geochemical analysis,multiple sets of Milankovitch cycles in this set of strata are identified.Based on the 404.858 ka long eccentricity.period,the"floating"astronomical scale of the Yingxiongling shale is established.[Results]The sedimentation time of the Yingxiongling shale is approximately 4.86 Ma,with an average sedimentation rate of 340.44 m/Ma.This high sedimentation rate is a key characteristic of the Yingxiongling shale.The sedimentary response characteristics related to the total organic carbon content based on long eccentricity period analysis revealed that the degree of organic carbon enrichment in the Yingxiongling shale in the Qaidam Basin was controlled by the sedimentation rate.As the deposition rate increased,the total organic carbon content also increased.However,when the deposition rate exceeds 450 m/Ma,total organic carbon decreases significantly due to the dilution effect of detrital materia.Furthermore,the sedimentary structure response model developed from precession period analysis shows that when the precession parameter is at its minimum,the primary development consists of poorly organic matter-rich layered limestone.In contrast,when the precession parameter was at the maximum value,the predominant development features limestone rich in organic matter.[Conclusion]The obvious orbital forced response exhibited by the Yingxiongling shale will assist in predicting favorable sections of shale oil and provide new assist in for the efficient exploration and development of Yingxiongling shale oil i

关 键 词：柴达木盆地 英雄岭页岩 天文旋回 高沉积速率 充填响应 

分 类 号：P618.12[天文地球—矿床学]