川西新场裂隙储层波场模拟与分析

Wave Field Simulation and Analysis of Fracture Reservoir in Xinchang, Western Sichuan

川西坳陷致密碎屑岩储层虽然地质储量丰富,但是复杂地质条件导致的储层物性差、分布广、层系多、裂隙发育、非均质性强、流体关系复杂的特点加剧了勘探开发的难度。本文针对川西新场探区的复杂性和特殊性,将裂隙储层等效为各向异性储层,进行VTI介质和HTI介质波动方程正演模拟,分析该地区裂隙介质的地震响应特征。波场模拟结果分析表明,裂隙介质的存在,会引起反射波场的振幅和走时变化;另一方面,根据走时的变化,也能估算裂缝发育角度范围。

Although the tight clastic rock reservoir in Western Sichuan depression is rich in geological reserves, the characteristics of poor physical properties, wide distribution, many strata, fracture development, strong heterogeneity and complex fluid relationship caused by complex geological conditions aggravate the difficulty of exploration and development. In view of the complexity and particularity of Xinchang exploration area in Western Sichuan, the fracture reservoir is equivalent to anisotropic reservoir, the wave equation forward modeling of VTI and HTI media is carried out, and the seismic response characteristics of fracture media in this area are analyzed. The analysis of wave field simulation results shows that the existence of fracture medium will cause the amplitude and travel time changes of reflected wave field;on the other hand, according to the travel time changes, the fracture development angle range can also be estimated.