塔里木盆地富满油田东部走滑断裂发育特征与油气成藏

Strike-slip faults and hydrocarbon accumulation in the eastern part of Fuman oilfield， Tarim Basin

宋兴国 陈石 谢舟 康鹏飞 李婷 杨明慧 梁鑫鑫 彭梓俊 史绪凯

Xingguo SONG Shi CHEN Zhou XIE Pengfei KANG Ting LI Minghui YANG Xinxin LIANG Zijun PENG Xukai SHI

富满油田东部走滑断裂是塔里木盆地奥陶系超深层碳酸盐岩油气藏勘探的重点目标。该走滑断裂活动较弱，识别解译难度较大，需要深入研究其发育、演化及控藏特征。基于富满油田最新采集的三维地震数据，选取并精细解译了3条典型主干断裂（F10，F12和F17），明确了富满油田东部走滑断裂活动特征及主要活动期次。在此基础上，结合油气性质及成藏期次，分析了断裂活动特征与油气成藏的关系，加深了对该区域断裂发育特征与油气分布规律的认识，进一步明确了断裂演化与油气成藏的耦合关系对油气性质的影响。研究表明，富满油田内走滑断裂具有垂向分层差异变形特征，可划分出4个构造变形层，由下往上分别为盐下基底构造层（T之下）、盐构造层（T—T）、碳酸盐岩构造层（T—TO）和碎屑岩构造层（TO之上）。研究区断裂活动期次整体可划分为加里东早期、加里东中期Ⅲ幕和加里东晚期—海西期3个阶段，其中加里东中期Ⅲ幕是区域内断裂主要活动阶段。结合油气性质差异、油井生产动态、断裂活动特征与油气成藏期的耦合关系认为，断裂活动影响了垂向运移通道的开启，控制了油气垂向运移；断裂持续活动时间长，使油气运移通道保持开启，有利于晚期高成熟油气的持续充注，造成断控油气藏具有油气充注强度大、成熟度高及气/油比高的特征。

The strike-slip faults in the eastern Fuman oilfield have been targeted for Ordovician ultra-deep carbonate reservoirs in the Tarim Basin. However， they are difficult to be identified and interpreted with available data due to their weak activity， thus it is essential to deeply understand their development， evolution and reservoir-controlling characteristics. Based on the newly acquired 3D seismic data of the oilfield， three typical trunk faults （F10， F12 and F17） are selected for a fine interpretation to clarify the activity characteristics and main faulting stages of the strike slip faults. Combined with oil and gas properties and reservoir-forming stages， the study analyzed the relationship between fault activity characteristics and hydrocarbon accumulation to deepen the understanding of fault development characteristics and hydrocarbon distribution in the area as well as clarifying the coupling relationship between multi-stage evolution of faults and multi-stage accumulation of hydrocarbons. The results show that the strike-slip faults in the Fuman oilfield has the characteristics of vertical stratified differential deformation， which can be divided into four tectonic deformation layers from bottom up： the subsalt basement tectonic layer （below T?）， salt tectonic layer （T?-T?）， carbonate rock tectonic layer （T-TO） and clastic rock tectonic layer （above TO）. The active faulting can be divided into three stages： the early Caledonian， the third episode of the middle Caledonian and the late Caledonian-Hercynian， among which the third episode of the middle Caledonian is the main active faulting stage. Combined with the coupling relationship between the difference of oil and gas properties， the production performance of oil wells， the characteristics of fault activity and the period of hydrocarbon accumulation， comprehensive analyses show that faulting affects the opening of vertical migration pathway and controls the vertical hydrocarbon migration. The faulting lasts for a long time， which keeps the hydrocarbon migration pathways open and is conducive to the continuous charging of late highly mature oil and gas， resulting in fault-controlled reservoirs characterized by high hydrocarbon charging intensity， high maturity and high gas-oil ratio.

10.11743/ogg20230207