碳酸盐岩生物礁地震响应特征的数值模拟

针对碳酸盐岩生物礁储层具有较强非均质性的特点,利用叠前黏弹性波动方程正演数值模拟方法,模拟了碳酸盐岩生物礁、滩的地震响应特征,为地震资料识别生物礁储层提供依据.模拟结果显示,在生物礁两侧出现上超反射,礁顶明显见披覆现象,在礁体内部产生S形前积反射、弱反射或杂乱反射,在礁前缘斜坡相外形呈楔状且礁底为下超反射终止.此外,礁体顶底界反射产生极性反转,底部反射同相轴可能出现上凸或下凹现象,而深度域成像剖面可以消除上凸或下凹现象.

Numerical simulation of seismic response characteristics of carbonate reef

Based on the nonhomogeneous characteristics of carbonate reef reservoirs,seismic forward modeling was conducted to simulate the seismic responses of carbonate reefs and beaches using the pre-stack viscoelastic wave equation,in order to provide a basis for identification of carbonate reef reservoirs according to seismic data.The simulation results show that the superposed overtaking reflection occurred on two sides of the reef and the drape covering phenomenon appeared over the reef.S-shaped forward sedimentary,weak,and mussy reflections took place inside the reef.The outer shape of the ramp facies in the reef front-edge appeared wedgy and the overtaking reflection stopped at the bottom.Moreover,reverse polarity occurred between the top and bottom reflections inside the reef.The bottom reflection presented upward-convex or downward-concave characteristics.These could be eliminated in the depth image profile.