石油与天然气地质 ›› 2018, Vol. 39 ›› Issue (4): 749-758.doi: 10.11743/ogg20180412

• 油气勘探 • 上一篇    下一篇

塔里木盆地顺托果勒地区志留系柯坪塔格组米兰科维奇旋回沉积记录

贾东力1, 田景春1, 林小兵1, 杨国华2, 冯文新2, 张翔1, 唐艳3, 杨辰雨4   

  1. 1. 成都理工大学 沉积地质研究院, 四川 成都 610059;
    2. 郑州工业贸易学校, 河南 郑州 450007;
    3. 四川省第三测绘工程院, 四川 成都 610500;
    4. 四川省地质矿产勘查开发局, 四川 德阳 618000
  • 收稿日期:2017-12-15 修回日期:2018-05-09 出版日期:2018-08-28 发布日期:2018-07-23
  • 通讯作者: 林小兵(1980-),男,博士、讲师,沉积学与储层地质学。E-mail:linxiaobing07@cdut.cn E-mail:linxiaobing07@cdut.cn
  • 作者简介:贾东力(1988-),男,博士研究生,层序地层学与沉积学。E-mail:25944718@qq.com。
  • 基金资助:
    中国地质调查局地质调查项目(1212011220760);成都理工大学沉积地质学科研创新团队项目(KYTD201703)。

Milankovitch cycles in the Silurian Kepingtage Formation in Shuntuoguole area,Tarim Basin

Jia Dongli1, Tian Jingchun1, Lin Xiaobing1, Yang Guohua2, Feng Wenxin2, Zhang Xiang1, Tang Yan3, Yang Chenyu4   

  1. 1. Institute of Sedimentary Geology, Chengdu University of Technology, Chengdu, Sichuan 610059, China;
    2. Zhengzhou Industry and Trade Schools, Zhengzhou, Henan 450007, China;
    3. The Third Academy of Engineering of Surveying and Mapping, Chengdu, Sichuan 610500, China;
    4. Geochemistry Exploration Brigade of Sichuan Bureau of Exploration and Development of Geology and Minerals Resources, Deyang, Sichuan 618000, China
  • Received:2017-12-15 Revised:2018-05-09 Online:2018-08-28 Published:2018-07-23

摘要: 塔里木盆地志留系柯坪塔格组主要沉积于盆地构造活动相对稳定期的潮坪环境,是盆地内典型的海相碎屑岩地层之一,由多层中-细砂岩和泥岩频繁互相叠置而成,地层分布上具有明显的三段特性。根据前人已有研究成果,柯坪塔格组在国际地层表上对应于特列奇阶、埃隆阶及鲁丹阶,沉积时限应介于8.1~12.7 Ma。然而目前对其米兰科维奇高频地层旋回格架划分鲜有探讨,通过选择顺托果勒地区顺9井自然伽马测井曲线作为替代指标,运用频谱分析法进行计算。结果表明顺9井柯坪塔格组记录并保存了完整的米兰科维奇旋回,天文旋回周期在地层沉积过程中对旋回厚度具有明显的控制作用。其中旋回厚度16.73 m对应于405 ka长偏心率周期;5.24 m和3.92 m分别对应于125 ka和95 ka的短偏心率周期;1.59 m和1.26 m分别对应于38.1 ka和31.1 ka的斜率周期。地层平均沉积速率为4.15 cm/ka,沉积时限为10.4 Ma,通过经验模态分解法建立了顺9井柯坪塔格组"浮动"天文年代标尺。柯坪塔格组共记录了83个125 Ka短偏心率旋回,334个31.1 ka周期斜率旋回。最后结合Fischer图解法,以125 ka短偏心率周期作为控制的五级旋回划分的标准模式,分析各个高频旋回之间的叠加差异及成因。该结果为盆地内或类似盆地海相碎屑岩高频旋回划分提供了一种统一的,不受人为影响且行之有效的新方法。

关键词: 米兰科维奇旋回, 频谱分析, 经验模态分解, 天文年代标尺, 柯坪塔格组, 志留系, 塔里木盆地

Abstract: The Silurian Kepingtage Formation in the Tarim Basin is mainly deposited in the tidal flat environment during a relatively stable period of tectonic activity.It is one of the typical marine clastic sequences in the basin.And it is composed of frequently alternating and superimposing medium-fine sandstone and mudstone,and can be obviously divided into three intervals.According to previous research results,the Kepingtage Formation can be approximately correlated with the Telychian,Aeronian and Rhuddanian Stage of the International Stratigraphic Chart,and its deposition period should be within 8.1-12.7 Ma.However,its Milankovitch high-frequency stratigraphic cycle framework is rarely discussed.Ta-king the Gamma-Ray logs of Well Shun-9 as proxies and using spectral analysis method for computation,we found that the Kepingtage Formation in Well Shun-9 recorded the complete Milankovitch cycle.The astronomical cycle significantly controls the cycle thickness,with the cycle thickness of 16.73 m corresponding to the long eccentricity of 405 ka,the cycle thickness of 5.24 m and 3.92 m corresponding to the short eccentricity of 125 ka and 95 ka respectively,and the cycle thickness of 1.59 m and 1.26 m corresponding to the obliquity of 38.1 ka and 31.1 ka respectively.The average sedimentary rate was estimated as 4.15 cm/ka and the depositing time as 10.4 Ma.And a "floating" astronomical time scale was established for the Kepingtage Formation in Well Shun-9 based on Empirical Mode Decomposition(EMD).The Kepingtage Formation was found to have 83 cycles with short eccentricity of 125 ka and 334 cycles with obliquity of 38.1 ka.Finally,we analyzed the superposition differences and their causes of each high-frequency cycle by using the Fischer plots and a standard model for fifth-order cycle division under the control of the short eccentricity of 125 ka.This result provides a new method that is unified and unbiased for high-frequency cycle division of marine clastic strata in this basin and similar basins.

Key words: Milankovitch cycle, spectral analysis, EMD, astronomical time scale, Kepingtage Formation, Tarim Basin

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