准噶尔盆地西北缘百口泉区前陆冲断带撕裂断层特征及控藏作用

Characteristics and controlling over reservoir accumulation of tear fault in foreland thrust belt of Baikouquan area in the northwestern margin of Junggar Basin

以理论分析为基础，结合区域构造背景，阐述了撕裂断层的基本特征和识别标志。撕裂断层断面近直立，在地震剖面上多表现为波组错断、同相轴紊乱等特征；在水平时间切片上，表现为同相轴扭曲、宽窄和产状变化等特征；在测井曲线主要表现为隔夹层的频繁出现以及锯齿化程度的增强。研究表明，准噶尔盆地西北缘百口泉区三叠系具有一定规模的撕裂断层8条，延伸长度3～7km。在此基础上，分析认为撕裂断层既可形成有效的运聚通道，又能够起遮挡作用而形成圈闭，对油气的运聚成藏具有重要的控制作用。

According to theoretical analysis, the features and recognition marks were described combined with the regional tectonic setting. The fault plane of tear fault is nearly vertical, and it usually shows discontinuity of wave group, disorder of seismic event on seismic section. On horizontal time slice, it reveals distortion, variation in width and attitude of seismic event. While for well logs, it results in the increase of interlayer frequency, and enhancement of sawtoothed curve. A certain size of northwest directional tear faults was firstly discovered in the northwestern margin of Junggar Basin. There are eight tear faults in Triassic strata of Baikouquan area, which extended from three to seven kilometers. The tear faults can not only be effective pathways for oil and gas migration and aecumulation, but also block off the oil and gas on the side, and it has significant effects on hydrocarbon migration and accumulation.