米兰科维奇旋回定量恢复碳酸盐岩地层剥蚀量:以塔里木盆地轮南古隆起奥陶系为例  

Quantitative Restoration of Eroded Carbonate Strata Thickness by Milankovitch Cycle:A Case Study of Ordovician Strata in Lunnan Paleo-Uplift,Tarim Basin

作　　者：马德波[1] 王媛 陈秀艳[1] 王珊[1] 杨敏[1] 杜德道[1] Ma Debo;Wang Yuan;Chen Xiuyan;Wang Shan;Yang Min;Du Dedao(PetroChina Research Institute of Petroleum Exploration and Development,Beijing 100083,China)

机构地区：[1]中国石油勘探开发研究院,北京100083

出　　处：《地球科学》2023年第8期2933-2946,共14页Earth Science

基　　金：中国石油天然气股份有限公司“十四五”专项“海相碳酸盐岩致密储层成藏机理、富集规律与勘探评价技术研究”(No.2021DJ0504);中国石油天然气股份有限公司科技项目“新区新领域综合地质研究与风险目标评价”(No.2022KT0406)。

摘　　要：剥蚀量定量恢复对盆地构造研究意义重大.以塔里木盆地轮南古隆起奥陶系一间房-鹰山组为例,通过钍钾比(Th/K)曲线的米兰科维奇旋回分析定量恢复碳酸盐岩地层剥蚀量,取得3项认识:(1)一间房-鹰山组米兰科维奇旋回特征清晰,较长偏心率周期(413 ka、125 ka)不发育,短偏心率周期(95 ka)、斜度周期、岁差周期较为发育.(2)一间房-鹰山组发育86个短偏心率周期旋回,通过对比剥蚀区与内幕区短偏心率周期旋回数量差异,定量恢复8口井剥蚀量.(3)一间房-鹰山组剥蚀区位于H6-TS2-TS1-LG36井以北,存在西北部、北部两个剥蚀中心,剥蚀量分别超过300 m和250 m.研究成果证实米兰科维奇旋回分析可实现碳酸盐岩地层剥蚀量定量恢复,对海相盆地古构造恢复具有良好的借鉴意义.It is of great significance to quantitatively restore eroded strata for tectonic study in a basin.In this paper,through spectral analysis of the ln(Th/K) curve,an indicator of climate variation resulting from Milankovitch cycles,the eroded strata of Ordovician Yijianfang and Yingshan formations are quantitatively restored on Lunnan paleo-uplift of Tarim Basin.The following three results are concluded:(1)Milankovitch cycles are characterized by undeveloped longer eccentricity period(413 ka,125 ka),well developed short eccentricity period of 95 ka,slope period and precession period in Yijianfang and Yingshan formations.(2)There are 86 short eccentricity periods developed in Yijianfang and Yingshan formations.Erosion thicknesses in 8 wells are restored quantitively by comparing the amount of Milankovitch cycles in short eccentricity period in denudation zones and inside strata.(3)Distributed in the north of well zone H6-TS2-TS1-LG36,the denudation zones include northwestern and northern centers,with an erosion thickness of over 300 m and 250 m respectively.It is approved that Milankovitch cycle analysis is a proxy for quantitative restoration of eroded carbonate strata and provide insight for paleo-structures restoration in marine carbonate basins.

关 键 词：剥蚀量恢复 米兰科维奇旋回分析 塔里木盆地 古构造复原 碳酸盐岩 构造地质 

分 类 号：P548[天文地球—构造地质学] P535[天文地球—地质学]