## 4 Case Analysis
### Comprehensive Analysis  
From ZK I, ZK II and ZK III borehole unfolding images, the distribution characteristics of the structural plane of the drilled rock mass and the texture characteristics of the rock can be clearly seen. The digital image processing technology is used to analyze the occurrence of the structural plane of each borehole rock mass, and the geometric parameter information such as the occurrence of the structural plane, gap width, spacing, etc., can be obtained, and the statistics and grouping can be carried out. The corresponding contour density nephogram and rose diagram of the structural plane are shown in Figure 15. Figure 15a,b shows the structural plane characteristics corresponding to borehole ZK I. Figure 15c,d shows the structural plane characteristics corresponding to borehole ZK II. Figure 15e,f shows the structural plane characteristics corresponding to borehole ZK III. Borehole radar detection is based on the different reflection amplitude and phase of the electromagnetic wave when it encounters different reflection interfaces to judge the change of the propagation medium ahead. The difference in the dielectric constant of the medium determines the intensity of electromagnetic wave reflection and its phase. The change of lithology, structure, weathering degree and water content will affect its dielectric constant. The interpretation of radar test data is based on the radar image of the field test; the data processing is carried out first, and then the abnormal analysis of the image that can be interpreted is carried out. According to the shape and characteristics of the anomaly and the attenuation of the electromagnetic wave, the geological origin of the wave impedance  
Figure 15: Contour density nephogram and rose map of structural plane. (**a**) Contour density nephogram of borehole ZK I. (**b**) Rose diagram of borehole ZK I. (**c**) Contour density nephogram of borehole ZK II. (**d**) Rose diagram of borehole ZK II. (**e**) Contour density nephogram of borehole ZK III. (**f**) Rose diagram of borehole ZK III. interface can be determined so that the geological conditions within the test range can be explained. After completing the acquisition and analysis of the radar data of the three boreholes, the borehole radar data are comprehensively interpreted in combination with the borehole image data and borehole directional acoustic scanning data, and the results are shown in Figure 16.  
It can be seen from Figure 16a that there are mainly cracks and small holes at different depths of borehole ZK I. It can be seen from Figure 16b that cracks and small holes mainly exist at different depths of borehole ZK II. It can be seen from Figure 16c that there are mainly small holes at different depths of borehole ZK II. In the survey of borehole holes using borehole optical imaging technology, the structural characteristics of rock mass inside the borehole can be effectively observed and measured, and the distribution characteristics of the structural plane of the borehole rock mass and the texture characteristics of the rock can be clearly seen. At the same time, the geometric parameter information such as the occurrence of the structural plane, gap width, spacing and so on can also be obtained. However, it is difficult to determine whether the rock mass structure around the borehole is abnormal by using borehole optical imaging technology. In addition, it is difficult to predict the extent of extension and development trend of the rock mass structural plane in a certain range far from the borehole. In the survey of boreholes using borehole radar technology, it can effectively judge the possible abnormal rock mass structures around the borehole, such as karst caves and cracks. However, the data obtained by using the borehole radar system alone are multi-solution and directionless, and it is difficult to obtain the dielectric constant of rock mass, which leads to difficulty in accurately defining the range of abnormal structures.