## 3 Results and Discussion
Lineaments extracted from study area 1 and 2 by the traditional Canny algorithm (n represents the number and intersections of lineaments). Figure 15: Digital lineament strength and density map (n represents the number and intersections of the lineaments) in measured region 1 and 2. In addition, to further compare the three data and analyze the variability of their structure, this paper quantifies and visualizes the spatial variability of the fracture structure. By creating a semi-variance function diagram, Surfer software is used to draw a two-dimensional contour image of the gridded semi-variance function data. To determine the overall direction of the extracted lineaments, the experimental results are shown in Figures 18-20: \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline  & **Region 1** & **Field** & **Traditional** & **Improved** & **Region 2** & **Field** & **Traditional** & **Improved** \\  & **Survey** & **Method** & **Method** & **Method** & **Survey** & **Method** & **Method** \\ \hline  & n & 508 & 493 & 464 & N & 503 & 485 & 472 \\ Lineament & x & 0.5125 & 0.3593 & 0.4742 & x & 0.7284 & 0.3890 & 0.4563 \\ Strength & s & 0.3656 & 0.2939 & 0.3556 & S & 0.4823 & 0.3072 & 0.3330 \\  & s\({}^{2}\) & 0.1337 & 0.0864 & 0.1264 & s\({}^{2}\) & 0.2326 & 0.0944 & 0.1109 \\  & Cv & 0.7135 & 0.8179 & 0.7498 & Cv & 0.6621 & 0.7897 & 0.7300 \\ \hline  & n & 356 & 283 & 321 & N & 440 & 310 & 323 \\ Lineament & x & 0.0886 & 0.0512 & 0.0941 & x & 0.1813 & 0.0599 & 0.0891 \\ Density & s & 0.1126 & 0.0753 & 0.1292 & S & 0.1937 & 0.0815 & 0.1017 \\  & s\({}^{2}\) & 0.0127 & 0.0057 & 0.0166 & s\({}^{2}\) & 0.3751 & 0.0066 & 0.0103 \\  & Cv & 1.2705 & 1.4714 & 1.3733 & Cv & 1.0682 & 1.3605 & 1.1413 \\ \hline  & & & & & & & & \\ \end{tabular}
\end{table} 
Table 2: Lineament strength and density with the three methods. Figure 17: Digital lineament strength and density map. Lineaments extracted from study area 1 and 2 by the improved line tracking method (n represents the number and intersections of lineaments). Figure 19: Semi-variance contour map of fracture strength and fracture density of lineaments in study area 1 and study area 2 extracted by the traditional Cannny algorithm. Figure 18: Measured data study area 1 and study area 2; fracture strength and fracture density half variance contour map. It can be seen from the experimental results that in the field measurement data extracted by the circular scanning line method, the fault strike attribute near the side of the Lianhuashan fault is about NE45\({}^{\circ}\), which is similar to the trend of the Lianhuashan fault. The fracture strike attribute near the Wuzishan antichinori is about NE20\({}^{\circ}\), which is close to the axial direction of the Wuzishan antichinorium. Because the accuracy and scale of the image, the Landsat 8 Oli image and DEM image in the field survey study area are different, so for the experimental results, we only count the same points of the fracture attributes in the three images, namely fracture density and fracture strength, to compare the lineament results extracted by the two algorithms with the field measurement data. The results are shown in Table 3.  
It can be seen from the table that the linear tectonic trend in study area 1 extracted by traditional Canny algorithm is NE62\({}^{\circ}\). The lineament trend in the study area 2 is extracted to be NE32\({}^{\circ}\); based on the improved line segment tracking method, the lineament trend in the study area 1 is NE47\({}^{\circ}\). The lineament trend in the study area 2 is extracted to be NE26\({}^{\circ}\). The fracture tendency in the three groups of data is the same. Therefore, it can be