| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 4681658 | Geoscience Frontiers | 2013 | 8 Pages |
The unconformity surface at the bottom of the Paleogene is one of the most important migration pathways in the Sikeshu Sag of the Junggar Basin, which consists of three layers: upper coarse clastic rock, lower weathering crust and leached zone. The upper coarse clastic rock is characterized by higher density and lower SDT and gamma-ray logging parameters, while the lower weathering crust displays opposite features. The transport coefficient of the unconformity surface is controlled by its position in respect to the basal sandstone; it is higher in the ramp region but lower in the adjacent uplifted and sag areas. The content of saturated hydrocarbons increases with the decrease of the content of non-hydrocarbons and asphaltenes. The content of benzo[c] carbazole decreases as the content of benzo[a] carbazole and [alkyl carbazole]/[alkyl + benzo carbazole] increases. This suggests that the unconformity surface is an efficient medium for the transportation of hydrocarbons.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► The Paleogene Sikeshu unconformity surface consists of upper clastic, lower weathered and leached beds. ► The transport coefficient of the unconformity surface is higher at ramp and lower in uplift/sag. ► The unconformity surface provides efficient hydrocarbon transportation and accumulation.
