A study of flow path in Yuquanshan area of western Beijing based on integrated geophysical technology

In order to investigate the features of strata configuration and fault structure and study the karst water flow path in Yuquanshan area of western Beijing, the authors carried out integrated geophysical survey in the surrounding area of Yuquanshan and completed regional gravity survey 107 km² in area with 3670 measurement points. On the basis of the explanation of gravity anomaly, 5.1km controlled source audio-frequency magnetotellurics (CSAMT) profiles and 4 microtremor measurement points were carried out. According to these geophysical data, the basement relief and structure distribution were comprehensively studied, and 10 possible faults were interpreted and deduced. Combined with regional hydrogeological data, the hydrogeological significance of the main faults was studied. Then a new understanding of the strong karst water flow path in Yuquanshan area was obtained, which is consistent with the result of the latest isotope and hydrochemistry studies. This study provides the geophysical support for determining a reasonable recharge program for the restoration of Yuquanshan spring.