四川盆地高石梯—磨溪地区走滑断层识别

四川盆地高石梯—磨溪地区二叠系栖霞组不断发现天然气，油气勘探潜力巨大。张扭性走滑断层控制着油气分布，但目前对于走滑断层特征的研究较少，并且仅根据地震剖面识别走滑断层具有局限性。为此，从走滑断层形成的力学机制入手，分析构造样式及构造特征，并以海豚效应和丝带效应指导走滑断层识别；分析、对比多种地震属性优、缺点，优选最适合走滑断层识别的地震属性。研究认为：高石梯—磨溪地区走滑断层主要受里德尔剪切的单剪模式控制；剖面上表现为正花状构造、线状构造、“Y”字型构造及多期花状构造叠加等构造样式，具有断距小、层位错动不明显、以同相轴弯曲扰动为主的特征；平面上具有辫状构造、雁列状构造、马尾构造等多种构造样式，沿断层走向具海豚效应，沿断层倾向具丝带效应；基于波形相似性相干算法的地震属性分析识别走滑断层效果较差，曲率属性和蚂蚁体属性可较清晰地识别走滑断层平面展布特征。该方法可为其他同类地区走滑断层识别提供参考。

Identification of strike-slip faults in Gaoshiti-Moxi area of Sichuan Basin

Natural gas is continuously discovered in the Permian Qixia Formation in the Gaoshiti-Moxi area of the Sichuan Basin, and thus this area has great potential for oil and gas exploration. Transtensional strike-slip faults control the distribution of oil and gas, but there is little research on the characteristics of strike-slip faults, and it is insufficient to identify strike-slip faults only according to seismic profiles. Therefore, starting with the mecha-nical mechanism of the formation of strike-slip faults, this paper analyzes the structural styles and structural characteristics and guides the identification of strike-slip faults with the dolphin effect and ribbon effect. Moreover, the advantages and disadvantages of various seismic attributes are analyzed and compared, and the seismic attributes most suitable for strike-slip fault identification are selected. The study believes that the strike-slip faults in the Gaoshiti-Moxi area are mainly controlled by the single shear mode of Riedel shear. On the section, the structural styles include the positive flower structure, linear structure, Y-shaped structure, and the superposition of multi-stage flower structures, which are characterized by small fault displacement, unobvious horizon dislocation, and dominant event bending disturbance. On the plane, structural styles include the braided structure, en-echelon structure, and horsetail structure, and the dolphin effect and ribbon effect appear along the fault strike and the fault dipping direction, respectively. The seismic attribute ana-lysis by the waveform similarity-based coherence algorithm has a poor identification effect of strike-slip faults, while the curvature and ant body attributes can clearly identify the planar distribution characteristics of strike-slip faults. This method can provide a reference for the identification of strike-slip faults in other similar areas.