Oil maturity assessment using maturity indicators based on methylated dibenzothiophenes

作     者：Li Meijun Wang T.-G Shi Shengbao Zhu Lei Fang Ronghui 

作者机构：State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum College of Geosciences China University of Petroleum 

出 版 物：《Petroleum Science》 (石油科学（英文版）)

年 卷 期：2014年第11卷第2期

页      面：234-246页

核心收录：

学科分类：081803[工学-地质工程] 08[工学] 0818[工学-地质资源与地质工程] 

基　　金：funded by the National Natural Science Foundation of China (Grant No. 41272158) the State Key Laboratory of Petroleum Resources and Prospecting (PRP/indep-2-1302) 

主　　题：Dibenzothiophene maturity indicator molecular thermodynamic stability sedimentaryorganic matter 

摘      要：Aromatic fractions of 140 oils and condensates that originated from different types of source rocks （marine shale,terrestrial shale and marine carbonate） were analyzed using gas chromatographymass spectrometry （GC-MS） to investigate the relative distributions of methylated dibenzothiophenes with respect to thermal *** positions of methyl groups of trimethyldibenzothiophene isomers （TMDBTs） including those used in the definition of maturity indicator TMDBT index in previous studies were firmly identified by co-elution of internal standards in GC-MS analysis and by comparing with reported retention indices.A new maturity ratio related to dimethyldibenzothiophenes （DMDBTs） is proposed on the basis of the differences in thermodynamic stability among different DMDBT *** maturity index （TMDBT-I2） based on TMDBTs is also suggested on the basis of our empirical observations and presumed thermodynamic stability of TMDBT *** two newly proposed （2,6 ＋ 3,6）-/1,4-DMDBT ratio and TMDBT-I2 correlate well with MDR （4-/1-methyldibenzothiophene）and 2,4-/1,4-DMDBT ratios,suggesting their common chemical reaction mechanisms and similar behavior with increasing ***,they can be effectively applied for maturity ***,the TMDBTs related maturity parameters are more reliable for over-mature oils and condensates due to the relatively higher concentrations of thermodynamically unstable TMDBT isomers,i.e.1,4,6-,1,4,8-and 3,4,6-TMDBT in this study than those of 1-methyldibenzothiophene （1-MDBT） or 1,*** contrast with 4,6-/1,4-DMDBT,the newly proposed （2,6 ＋ 3,6）-/1,4-DMDBT ratios for oils that originated from different types of source rocks have approximately same relationship with the oil maturity （Rc %）.This suggests that the lithology and organic facies may have relatively less influence on （2,6 ＋ 3,6）-/1,4-DMDBT ratio compared to 4,6-/1,*** maturity parameters based on methylated dibenzothiophenes are particularl