# Detection of Rock Mass Defects Using Seismic Tomography
## 4 Application
### Results
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Section**} & \multirow{2}{*}{**The Serial Numbers of Stopes**} & \multicolumn{2}{c}{**The Goaf Area S1 Based on the Statistical Analysis of**} & \multicolumn{2}{c}{**The Goaf Area S2 Based on the Results of Physical**} & \multicolumn{2}{c}{**The Rate of Change, R, from S2 to S1**} \\  & & **Historical Data (m\({}^{2}\))** & **Detection (m\({}^{2}\))** & **R=\(\frac{5\text{m}-5\text{m}}{5\text{m}}\times\)100\%** \\ \hline \multirow{4}{*}{First Section} & 68160 & 497.96 & 520.2328 & 4.47\% \\  & 68132 & 481.95 & 270.9463 & \(-\)43.78\% \\  & 68134 & 507.22 & 559.0360 & 10.22\% \\  & 68136 & 553.93 & 500.1195 & \(-\)9.71\% \\  & 68138 & 319.20 & 312.7774 & \(-\)2.01\% \\ \hline \multirow{4}{*}{Second Section} & 68232 & 821.18 & 835.1407 & 1.70\% \\  & 68234 & 633.92 & 552.5929 & \(-\)12.83\% \\ \cline{1-1}  & 68238W & 491.07 & 549.2915 & 11.86\% \\ \cline{1-1}  & - & - & - & \\ \cline{1-1}  & 45261E & 365.28 & 369.5426 & 1.17\% \\ \cline{1-1}  & 63234E & 551.01 & 571.1484 & 3.65\% \\ \hline \multirow{4}{*}{Third Section} & 68334 & 306.18 & 312.0997 & 1.93\% \\  & 68336 & 250.01 & 252.0154 & 0.80\% \\ \cline{1-1}  & 68336E & 462.81 & 483.1273 & 4.39\% \\ \cline{1-1}  & - & - & - & \\ \cline{1-1}  & 45332E & 287.97 & 304.2145 & 5.64\% \\ \cline{1-1}  & 63334 & 407.58 & 417.9953 & 2.56\% \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Goaf area of different slopes derived from the statistical analysis of historical data and physical detection, with comparative analysis of results. Figure 10: The layout of the results based on physical detection. The red area denotes non-extracted rock mass, while the white grid area indicates the goaf regions; the blue line delineates the boundaries of these goaf areas. Figure 12: Data distribution chart of goaf area of different slopes in second section, derived from the statistical analysis of historical data and physical detection, along with comparative analysis of these results. Figure 13: Data distribution chart of goaf area of different slopes in third section, derived from the statistical analysis of historical data and physical detection, along with comparative analysis of these results. Figure 14: Data distribution chart of goal area in different stopes in the fourth section, derived from the statistical analysis of historical data and physical detection, along with comparative analysis of these results. Figure 15: Data distribution chart of goal area of different stopes in fifth section, derived from the statistical analysis of historical data and physical detection, along with comparative analysis of these results. 1. The physical detection result for the goaf area of Stope 68132 in the first section is 43.78% lower than the historical statistical data, while the discrepancy between the physical detection outcomes and historical statistics for goaf areas in the other four stopes is a maximum of 10.22%. Consequently, it can be inferred that Stope 68132 may contain a goaf, whereas it is confirmed that all four other stopes within the first section have established goals. 2. The physical detection results for the goaf areas of stopes in the second section--specifically, 68261\({}_{\text{down}}\), 68263E\({}_{\text{down}}\), 68263W\({}_{\text{down}}\), 68261\({}^{\text{up}}\), 68263E\({}^{\text{up}}\), and 68263W\({}^{\text{up}}\), as well as stopes 45265E and 45263N--indicate significant decreases relative to historical statistical data by percentages of 83.69%, 76.13%, 86.05%, 78.29%, 79.85%, 76.00%, and 80.39%, respectively. Conversely, the physical detection results for goaf areas in stopes, such as those designated as 68240 and 68242W, show increases of approximately 67.35% and 58.95%. Additionally, changes in the goaf area results for stopes identified as both 68234E and 68242 were around 30%, while alterations in the remaining twelve stopes did not exceed 12.83%.