Smectite-illitization difference of source rocks developed in saline and fresh water environments and its influence on hydrocarbon generation: A study from the Shahejie Formation, Dongying Depression, China
Samples of argillaceous source rocks from three sub-members of the Shahejie Formation (Es) in the Dongying Depression, China, were collected to investigate the differences in hydrocarbon generation among the sub-members, which developed in fresh (Es 3 2 , Es 3 3 ) and saline (Es 4 1 ) water environments. Pyrolysis, XRD and thermo-XRD analyses were used to compare the characteristics of organic matter (OM), clay minerals and OM occurrences. Total organic carbon and hydrocarbon potential proxies suggest that the samples from Es 3 3 were much better than the other two intervals, which agrees with previous studies. The characteristics of clay minerals suggest that the samples from Es 4 1 have the most abundant illite, with a maximum illite percentage in mixed-layer illite-smectite (I?Sm), and the best crystallinity of I?Sm with a main stacking mode of R1.5. However, the stacking modes of I?Sm in Es 3 2 and Es 3 3 were primarily R0 and R1, respectively, and the crystallinity was relatively poor. Thus, the smectite illitization process was faster in Es 4 1 than in the other two intervals, and a saline environment was a primary cause for the acceleration of the process. Moreover, OM occurrence indicates that the samples from Es 4 1 had the lowest amount of interlayer OM, whereas Es 3 3 had the largest amount. Therefore, the rapid illitization in Es 4 1 caused abundant interlayer OM to be desorbed and discharged, which in turn caused the amount of residual interlayer OM in Es 4 1 to be less than that in the other two intervals. Thus, the source rocks of Es 4 1 made a more significant contribution to hydrocarbon generation than those of the other two units. In conclusion, the inconsistent illitization among these intervals was a major cause of the differences in hydrocarbon generation.
- 원문이 없습니다.
유료 다운로드의 경우 해당 사이트의 정책에 따라 신규 회원가입, 로그인, 유료 구매 등이 필요할 수 있습니다. 해당 사이트에서 발생하는 귀하의 모든 정보활동은 NDSL의 서비스 정책과 무관합니다.
원문복사신청을 하시면, 일부 해외 인쇄학술지의 경우 외국학술지지원센터(FRIC)에서
무료 원문복사 서비스를 제공합니다.
NDSL에서는 해당 원문을 복사서비스하고 있습니다. 위의 원문복사신청 또는 장바구니 담기를 통하여 원문복사서비스 이용이 가능합니다.
- 이 논문과 함께 출판된 논문 + 더보기