运用激电中梯测量探测覆盖型岩溶发育程度

Using the induced polarization intermediate gradien survey to investigate covered karst's development degree

运用激电中梯测量方法,进行岩溶塌陷地质灾害调查,研究了覆盖型岩溶的发育程度。首先研究了不同地层岩性的视电阻率和视极化率特征,得出了岩溶裂隙发育的主要地球物理特征;再根据研究区的激电中梯测量成果,划分了4个异常区;结合地质构造条件,推断解释认为Ⅰ区和Ⅲ区中的局部高阻区为岩溶裂隙发育区;最后通过布设电阻率垂向测深剖面,进行推断反演,并利用钻孔进行验证,发现了1.6 m深溶洞。研究成果表明,激电中梯测量方法在探测覆盖型岩溶的发育程度方面,取得了较好的效果。

In the paper, we used induced polarization intermediate gradien survey method to investigate karst collapse geological disaster and covered karst＇ s development degree in the area. Firstly, in order to summarize the main geophysical characteristics of the karst fracture we studied the different formation lithology of apparent resistivity and apparent chargeability characteristics. Secondly, according to the research results of induced polarization intermediate gradien survey, the area was divided into four anomaly area. Then we make investi- gation risk assessment of the karst collapse in the area, according to the result. And the most important is making the classification and evaluation of karst collapse. Combined with geological structure conditions, we deduced part high resistance areas both in I and m were karst fracture development zone. Finally, we discov- ered a 1.6 meters＇ deep karst - cave in the area, by setting the resistivity vertical sounding profiles and infer- ring inversion. Then drilling verification shows that there really is a karst - cave. Good results have been a- chieved by the induced polarization intermediate gradien survey method in detecting of the karst＇ s development degree. The results for economic development and location of the project to provide basic data, which will pro- vide the scientific basis for prevention of ground subsidence of geological disasters, in order to achieve the pur- pose of disaster prevention and mitigation.