| Title | Revised oil-source correlation models in the Chao-Chang region and implications for Lower Cretaceous petroleum play concepts in the Songliao Basin, NE China |
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| Author | Wang, X; Li, M ;
Feng, Z; Fang, W; Li, Z; Huo, Q; Achal, S; Milovic, M; Robinson, R; Huang, C; Song, G |
| Source | American Association of Petroleum Geologists, Annual Meeting Abstracts 2010. |
| Links | Online - En ligne
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| Image |  |
| Year | 2010 |
| Alt Series | Earth Sciences Sector, Contribution Series 20090476 |
| Publisher | American Asociation of Petroleum Geologists |
| Meeting | AAPG International Conference and Exhibition; Calgary; CA; September 2010 |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Area | Songliao; China |
| Subjects | economic geology; general geology; fossil fuels; exploration; petroleum exploration; petroleum; petroleum resources |
| Illustrations | location maps; stratigraphic charts; geological sketch maps; location maps; graphs; plots |
| Program | International Capacity Building and Trade and Investment (Program) ESS-China Hydrocarbon Geoscience Collaboration |
| Released | 2010 01 01 |
| Abstract | Biomarkers in 60 oil samples from the Chao-Chang region, Songliao Basin, NE China reveal three genetic oil groups and suggest characteristics of their probable source rocks. Group 1 (57 Lower and Upper
Cretaceous-reservoired oils over the entire region) was sourced from the Upper Cretaceous Qingshankou Formation (K2Qn1), the main petroleum source rocks in the basin. Group 2 (two Lower Cretaceous-reservoired oils in the Changchunling anticline zone)
and group 3 (one Lower Cretaceous-reservoired oil in the Sanzhao sag) derive from two high quality sources with more localized occurrence, corresponding to carbonate-evaporate and freshwater lacustrine facies, respectively. The relative abundance of
gammacerane in the group 1 oils suggests the deposition of their type I, algal rich, lacustrine source rocks under conditions of enhanced salinity-stratified water columns, consistent with those in the K2Qn1 member. The large variation in the
molecular maturity parameters of the group 1 oils (such as sterane isomerization ratios) was not substantiated by the gross oil compositions and n-alkane concentration. Although we did not intend to address source rock volumes in this molecular
study, there is clear evidence against the previously proposed model of downward oil migration from a local source. Instead, lateral migration of the oils derived from the younger K2Qn1 sources in the deeper parts of the Sanzhao and Wangfu sags
appears responsible for the occurrence of the group 1 oils in the older Lower Cretaceous reservoirs in the Chaoyanggou terrace and Changchunling anticline zones. The large variation in the biomarker concentrations in source rocks with different
maturity levels illustrates how the addition of small amounts of soluble organic matter from a local source (e.g. caprock and intra-reservoir shale) to a mature oil could potentially compromise its biomarker maturity parameters. Although most oils in
the study area derive from the Upper Cretaceous K2Qn1 source, the presence of other oil genetic groups suggests that future exploration in this region should also carefully consider the potential of the not yet penetrated, probably more localized,
Lower Cretaceous source rocks in the deeper parts of the basin. |
| GEOSCAN ID | 262735 |
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