热带海洋学报 ›› 2014, Vol. 33 ›› Issue (5): 50-59.doi: 10.11978/j.issn.1009-5470.2014.05.007

• 海洋地质学 • 上一篇    下一篇

盆地沉降史回剥分析的不确定性及参数影响*

谢辉1, 2, 周蒂1, 陈广浩1, 李鹏春1, 庞雄3, 李元平3, 赵美松4   

  1. 1. 中国科学院边缘海地质重点实验室, 中国科学院南海海洋研究所, 广东 广州 510301; 2. 中国科学院大学, 北京 100049; 3. 中国海洋石油(中国)有限公司深圳分公司, 广东 广州 510240; 4. 中国石化胜利油田有限公司地质科学研究院, 山东 东营 257000
  • 收稿日期:2014-01-22 修回日期:2014-04-14 出版日期:2014-09-29 发布日期:2014-09-29
  • 作者简介:作者简介:谢辉(1987~), 男, 江西省抚州市人, 在读博士研究生, 从事盆地分析研究。E-mail: xiehuihaoba@163.com
  • 基金资助:
    国家高新技术发展计划项目(2008AA093001); 国家科技重大专项(2011ZX05025-003-005); 国家自然科学基金项目(40976033)

Uncertainty and parameterization in backstripping of basin subsidence analysis

XIE Hui1, 2, ZHOU Di1, CHEN Guang-hao1, LI Peng-chun1, PANG Xiong3, LI Yuan-ping3, ZHAO Mei-song4   

  1. 1. Key Laboratory of Marginal Sea Geology, Chinese Academy of Sciences, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; 2. University of Chinese Academy of Sciences, Beijing 100049, China; 3. China National Offshore Oil Corporation (CNOOC) China Ltd-Shenzhen, Guangzhou 510240, China; 4. Geological Scientific Research Institute of Shengli Oilfield Co. Ltd., China Petroleum & Chemical Corporation (SINOPEC), Dongying 257000, China.;
  • Received:2014-01-22 Revised:2014-04-14 Online:2014-09-29 Published:2014-09-29

摘要: 回剥分析(backstripping)是盆地沉降史分析的核心方法, 应用极为广泛; 但对其分析结果的不确定性及参数对分析结果的影响的关注甚少。以珠江口盆地白云凹陷地区为例, 探讨了原始数据和选用参数(包括无钻井揭示的基底埋深和界面年龄、地层划分、孔隙度随深度变化曲线、沉积岩性、古水深和全球海平面变化等)对回剥分析结果的影响。理论分析和灵敏度试验表明, 无钻井揭示的基底埋深的误差影响回剥分析的所有结果; 界面年龄的误差仅影响对沉积速率和构造沉降速率的估计; 岩性的影响反映在选取密度和孔隙度随深度变化的曲线参数之中, 孔隙度在不同地区可能有较大差异; 而古水深是回剥分析参数中不确定性最大的因素, 古水深的误差不影响去压实厚度和沉积速率, 但却100%成为构造沉降量的误差。由于陆坡区古水深和岩性随位置的变化较大, 这两种参数对陆坡区回剥分析结果的影响尤为显著, 需要采用随位置而变的参数, 特别需要综合利用各种地质地球物理资料估计各地层沉积时的古水深变化。数据的不确定性及参数选取的不当有可能导致谬误的结果, 因此发表回剥分析结果时应该说明主要参数的选取依据, 而对于文献中发表的回剥分析结果则必须在考察其数据和参数的不确定性后才能考虑采用与否。

关键词: 回剥分析, 沉降史分析, 不确定性, 参数影响, 白云凹陷, 珠江口盆地

Abstract: Backstripping is an important and widely used method for basin subsidence analysis. Little attention has been paid on the uncertainty of its results. In this paper, we address this issue based on a study of the Baiyun Sag in the Pearl River Mouth Basin. We demonstrated through theoretical analysis and sensitivity tests that the uncertainty in the non-recovery of the basement depth will pass on to all the results of backstripping, but the uncertainty in age only affects the estimations of sedimentary and subsidence rates. Formation lithology influences the selection of porosity and density parameters. The porosity-depth curves of sandstone and shale vary from area to area. Largest uncertainty comes from paleo-water depth, whose error is 100% inherited by the calculated tectonic subsidence. In the slope area, paleo-water depth and lithology vary significantly with locations. Thus, it is essential to use the paleo-water depth and lithology parameters that are variable with locations. The uncertainty in the source data and inappropriate parameters may lead to erroneous results. Caution should be taken when reading published backstripping results. The quality of parameterization needs to be examined before adopting the results.

Key words: backstripping, subsidence analysis, uncertainty, parameters, Baiyun Sag, Pearl River Mouth Basin

中图分类号: 

  • P736