【摘要】 为了解决地下复杂微小构造的精细勘探问题,使用基于高斯射线束理论的逆高斯束叠加成像方法对井间地震反射波进行成像研究。井间地震常规射线类叠加成像方法由于覆盖次数受到限制,构造复杂区精细成像质量欠佳,而以波动方程为基础的井间地震偏移方法的成像时效性不高。本文方法借鉴高斯束合成地震记录的思想,将共炮集地震数据逆高斯束分解成共反射点道集数据,然后选取合适的面元进行共反射面元数据叠加,实现了井间地震逆高斯射线束共反射点叠加。与传统的VSP-CDP叠加成像方法相比,成像范围更加广泛,且适应复杂地质构造。该方法不仅能够对二维井间地震勘探资料进行成像,针对三维井间地震资料采用基于宽线处理思路的逆高斯束叠加成像方法仍可以处理复杂构造及斜井成像问题。理论模型及实际资料试算验证了本文研究方法的有效性与稳健性。更多还原

【Abstract】 To solve problems in small-scale and complex structural traps, the inverse Gaussian-beam stack-imaging method is commonly used to process crosswell seismic wave reflection data. Owing to limited coverage, the imaging quality of conventional ray-based crosswell seismic stack imaging is poor in complex areas; moreover, the imaging range is small and with sever interference because of the arc phenomenon in seismic migration. Thus, we propose the inverse Gaussian-beam stack imaging, in which Gaussian weight functions of rays contributing to the geophones energy are calculated and used to decompose the seismic wavefield. This effectively enlarges the coverage of the reflection points and improves the transverse resolution. Compared with the traditional VSP–CDP stack imaging, the proposed methods extends the imaging range, yields higher horizontal resolution, and is more adaptable to complex geological structures. The method is applied to model a complex structure in the K-area. The results suggest that the wave group of the target layer is clearer, the resolution is higher, and the main frequency of the crosswell seismic section is higher than that in surface seismic exploration The effectiveness and robustness of the method are verified by theoretical model and practical data.更多还原