核磁共振(NMR)技术探测地下水是目前唯一的直接找水的地球物理方法。与传统的地球物理方法相比具有高分辨力,高效率,信息量丰富和解唯一性等优点。利用核磁共振地下水探测系统可以高效率地进行区域水文地质调查,确定找水远景区,圈定地下水在三维空间内的分布,进而可靠地选定水井位置等。但是由于水中氢核产生的核磁共振信号的幅度小(纳伏级),要求探测系统的灵敏度高,将引入大量的自然和人为噪声,导致采集信号的信噪比低,解释结果不清楚。
本文用LMS自适应算法提高MRS信号的信噪比,用Hilbert变换提取MRS信号的包络信号,用线性拟合提取水文地质参数并通过仿真实验结果,验证了本文提出的数据处理方法的有效性和准确性。
(Nuclear magnetic resonance (NMR) technique to the detection of direct water division is the only geophysical method to find water. Compared with conventional high-resolution geophysical methods, efficient, informative unique advantages of reconciliation. Groundwater exploration using nuclear magnetic resonance system can efficiently carry out the regional hydrogeological investigation to determine the prospective areas to find water, delineation of ground water distribution in three-dimensional space, and then reliably the location of the selected wells. However, because the water proton NMR signal amplitude generated by small (Na V level), requiring high sensitivity detection systems, will introduce a large number of natural and man-made noise, resulting in low signal to noise ratio acquisition, interpretation of results is not clear.
In this paper, LMS adaptive algorithm improves the MRS signal to noise ratio, with the Hilbert transform to extract the signal envelope MRS signal ext)