三维弹性波全波形反演在小保当煤矿勘探中的应用研究

Application of 3D elastic wave full-waveform inversion in Xiaobaodang Coal Mine exploration

高效、安全和智能化的煤矿开采对煤层顶底板以及地下三维地质模型的精度要求越来越高,传统地球物理探测方法在成像分辨率和精度方面已无法满足实际需求。将三维弹性波全波形反演技术应用于陕西小保当一号煤矿112204工作面的地下三维地质模型构建,通过谱元法和GPU超算实现地震波高效和高精度正演模拟,发展了多尺度、多目标函数和多波的反演方法与技术,并使用测井先验信息进行正则化约束,降低反演的非线性和多解性,最终构建了112204采煤工作面三维弹性速度结构模型,对煤层的顶底板进行了高精度成像,精细刻画了煤层的三维空间展布,反演结果与测井结果吻合较好,实现了采煤工作面的透明化。

The efficient,safe and intelligent coal mining are demanding higher accuracy for models of roof and floor interfaces of coal seam and underground 3D geological structures,while the imaging resolution and accuracy of traditional geophysics detection methods are inadequate.So,3D elastic wave full-waveform inversion(FWI)was applied to construct subsurface 3D geological structures for the 112204 coal face of Shanxi Xiaobaodang No.1 Coal Mine.Spectral-element method and GPU super-computing technique were used to efficiently and accurately simulate the wave propagation.Multi-scale,multi-objective functions and multi-wave inversion methods and technologies were developed.The well-log data was used as prior information for regularization constraints,to reduce inversion non-linearity and uncertainty.Finally,3D subsurface elastic velocity structures of 112204 coal face were obtained.The roof and floor interfaces of coal seam were imaged with high-resolution(0.5 m).3D spatial distribution of the coal seam was finely characterized and delineated.The inversion results matched well with the well-logging data.Based on these results,the objective of transparent coal face was achieved.