Oil & Gas Geology ›› 2022, Vol. 43 ›› Issue (5): 1259-1270.doi: 10.11743/ogg20220520

• Methods and Technologies • Previous Articles     Next Articles

Oil-source correlation based on multivariate statistical analysis: A case study of the Bodong Sag, Bohai Bay Basin

Xihao Guo1(), Fanghao Xu1(), Xiaobo Huang2, Tao Jiang2, Haoran Liang1, Changzhi Li1, Zhichao Li1   

  1. 1.State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu University of Technology,Chengdu,Sichuan 610059,China
    2.Tianjin Branch of CNOOC,Tianjin 300459,China
  • Received:2021-09-24 Revised:2022-07-10 Online:2022-10-01 Published:2022-09-02
  • Contact: Fanghao Xu E-mail:419312387@qq.com;xufanghao17@cdut.edu.cn

Abstract:

Multivariate statistical analysis can comprehensively consider the interrelationship of multiple related parameters, and is of unique advantage in classification-based identification. It is thus an effective method for oil-source correlation with multiple suites of source rocks occurring simultaneously in a zone. However, no authors have conducted special research and analysis on the comparative application and applicability of diverse multivariate statistical methods to one case. There are multiple suites of source rocks developed in the Bodong Sag, Bohai Bay Basin, and the sources of oil and gas in different structures are extremely complex, which is the best case for oil-source correlation using multivariate statistical analysis. The comparison of principal component analysis (PCA), Fisher linear discriminant analysis (LDA) and Bayes LDA in terms of application shows that PCA cannot be applied to distinguish source rocks at different horizons, so it cannot be used for oil-source correlation in the Bodong Sag. However, the models established by Fisher and Bayes LDA can do this effectively, though neither of them could accurately identify oil of mixed sources. Based on the classification probability obtained from the Bayes LDA model, a discriminant model suitable for the Bodong Sag is established with the discriminant criteria of the Bayes model optimized, and four oil familys are identified in the Bodong Sag, with oil family A, B and C are derived from the source rocks of the third member of the Oligocene Dongying Formation (Ed3), the first to second member (Es1-2) and the third member (Es3) of the Eocene Shahejie Formation, respectively, and oil family D from the source rocks of Ed3and Es1-2.

Key words: discriminant model, linear discriminant analysis (LDA), multivariate statistical analysis, oil-source correlation, Bodong Sag, Bohai Bay Basin

CLC Number: