塔里木盆地北部跃参区块走滑断裂对油气成藏的控制

通过对跃参区块近30口单井及其生产动态的分析解剖,结合岩心观察、分析化验等资料,深入探讨了跃参区块"X"形共轭走滑断裂体系对奥陶系岩溶缝洞体形成及油气成藏的控制作用。走滑断裂带多期活动形成了大量的高角度构造裂缝,伴随后期热液流体改造而发育大型缝洞型储集体。油气沿主干走滑断裂带垂向向上运移后,再沿次级走滑断裂带发生再分配,控制着该区油气性质的变化及油气充注程度。主干走滑断裂带上油气充注程度高、原油物性好、已钻井产能较好,而次级走滑断裂带上油气充注程度低、原油物性相对偏差、已钻井产能也相对偏差。此外,走滑断裂带的展布方向、断裂左右盘的相对位置、离断裂带的远近等因素对油气富集也具有重要的控制作用。研究表明,近NE向走滑断裂带的上升盘是油气最富集的部位。

Strike-slip faults and their controls on hydrocarbon reservoirs in the Yuecan block of the Northern Tarim Uplift,Tarim Basin

We studied the production performance of about 30 wells in the Yuecan block of the Northern Tarim Uplift in the Tarim Basin, and considered the controls of the X-shaped strike-slip faults in the study area on the Ordovician fractured and vuggy system reservoirs, combined with core sample observations and testing. The strike-slip faults were active during multiple stages, and formed a large number of high-angle tectonic fractures, which developed a large fractured and vuggy system during the following thermal evolution. Oil and gas migrated upwards along the main strike-slip faults, then redistributed along secondary faults, and finally determined the hydrocarbon properties and charging extentin the study area. Reservoirs with a high charging degree and excellent crude oil properties were found in the main strike-slip faults, and the wells showed a good production performance. On the contrary, the secondary strike-slip faults had a low charge and poor crude oil properties, and the wells showed poorer production performance. In addition, the direction of strike-slip faults, the relative position of fault walls, and the distance to faults also played important roles in controlling hydrocarbon enrichment.Results showed that hydrocarbon was most enriched in the upper wall of the NE-oriented strike-slip faults.