## 3 Results
### Tectonic Significance of the Study Area  
Figure 10 shows the geological profile inferred from the seismic reflection data of the 2016 Hutubi earthquake. Figure 10 is modified from [PERSON] et al. [41]. The location of this profile is marked by the solid cyan line in Figure 1. Prominent fold-and-thrust belts developed in the North Tianshan foreland basin, with the solid lines indicating the interpreted faults and the dashed lines representing the axial planes. F1 denotes the Yamate fault, F2 the Junggar South Margin fault, and F3 the Horgos-Manas-Tugulu fault. The solid white circles indicate the aftershocks of the Hutubi earthquake, and the solid black lines passing through them are possible seismogenic faults. The yellow star marks the epicenter of the 1906 Manas earthquake, and the solid white circles indicate the aftershocks, whose \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Data Source** & **Strike (\({}^{\circ}\))** & **Dip (\({}^{\circ}\))** & **Slip Angle (\({}^{\circ}\))** & **Focal Depth (\({}^{\circ}\))** & **Magnitude (M\({}_{W}\))** \\ \hline USGS & 269 & 71 & 93 & 17.6 & 6.0 \\ \hline GCMT & 272 & 68 & 92 & 20.3 & 6.0 \\ \hline SCANDEC & 276 & 70 & 95 & 20 & 6.0 \\ \hline CENC & 277 & 69 & 88 & 19 & 6.0 \\ \hline IGCEA & 273 & 70 & 108 & 17.6 & 5.95 \\ \hline Present study & 276 & 70 & 98.77 & 17.85 & 5.98 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Parameters of the 2016 Hutubi earthquake derived from various sources. Figure 9: Coseismic fault slip model of the 2016 Hutubi earthquake. The blue pentagram denotes the focus of the earthquake, and the white arrows are the motion vectors of discretized fault slips. spatial distribution implies that the seismogenic fault should be a north-dipping fault. However, as no north-dipping faults have been detected in this region, we suggest that the mainshock of the Hutubi earthquake might have occurred on a north-dipping blind fault at a depth of 5-20 km. This structure is extremely similar to the fault model obtained by the inversion described above; this also verifies that the inverted fault model fulfils the research requirements and expectations. F2 and F3 extend downward and finally intersect the detachment plane at a depth of about 24 km. Between them, strata of different ages overlap to form a wedge structure. The geological structures depicted in this figure are extremely complex, and the deformation characteristics of these faults and their related folds are similar to those of large-scale wedge structures [63; 64; 65], being composed of small wedges formed under forward and backward thrusts [66]. Blind faults usually occur as individual faults, sets of faults, or thrust systems. The overlapping strata may respond to a blind fault system by back-thrusting, coupling, forward-thrusting, or sedimentation [67]. The thrust structure of a large-scale tectonic wedge contains many blind faults, but F2 and F3, rupturing at the ground surface, are not blind faults. The Hutubi earthquake did not cause any surface rupture as its epicenter was deep, and its magnitude was not particularly great. The 1906 Manas earthquake occurred at a much greater depth, but historical records show that it caused considerable damage. According to its deep structural features and the regional tectonic background, this may have been because energy was released at a deep blind fault under the reactivated uplift of the Tianshan orogenic belt, which triggered tectonic activities at a shallow depth that resulted in violent crustal deformation. The young fault scarps along the Horgos-Manas-Tugulu thrust fault-anticline belt may be surface ruptures associated with the M 7.7 Manas earthquake [33; 68]. Therefore, we believe that the triggering mechanism of the 2016 Hutubi earthquake may be similar to that of the 1906 Manas earthquake, both of which were initiated by deep fault activities.