# Predicting Models for Local Sedimentary Basin Effect Using a Convolutional Neural Network
## 3 Basin DATABASE  
### Generation Method of Basin Models  
As shown in Figure 6, the flat topography in the interior of the basin provided a livable environment for human life, but the surrounding raised topography and the deep soil layer covering it had a significant amplifying effect on the ground motion. In order to study the basin amplification law, the real basin was usually simplified into a standard basin structure model [12]. According to the significant geometric characteristics of the flat center and the steep edge of the basin, a simplified 2D basin model of an \"inverted trapezoid\" was established, as shown in Figure 7.  
The aim of this study is to perform a comprehensive analysis of the seismic response of a typical 2D basin model with a wide range of geometric and material properties in order to study the response of the basin surface in relation to the basin geometry (width, thickness and slope angle of the lateral boundaries) and soil dynamic properties (shear and compression wave velocities, soil density, and attenuation), and in particular, to predict the potential hazard in the local basin area by determining the amplification characteristics of the peaks and the hazard location. The research showed that the amplification characteristics of 2D compared to 1D were mainly due to the influence of surface waves and 2D resonance. The factors influencing the characteristics were mainly shape ratio and wave velocity ratio. These represented the influence of geometry and medium properties in site conditions. As shown in Figure 8, the  
Figure 5: Activation function: (**a**) Sigmoid; (**b**) Tanh; (**c**) ReLU; (**d**) LeakyReLU. shape ratio was defined as \(H/2W\) where \(2W\) was the total width over which the sediment thickness was more than half of its maximum value. The wave velocity contrast \(C_{V}\) was defined as the ratio of the soil shear wave velocity to the bedrock shear wave velocity. The parameters related to the basin amplification effect were comprehensively considered to construct a series of numerical models for the basin surface seismic response analysis by varying the geometric parameters: thickness, shape ratio, edge dip angle (shown in Figure 8), and soil medium parameters such as shear wave velocity, density, Poisson's ratio, quality factor, damping ratio, etc. In order to investigate the sensitivity of the 2D seismic response of trapezoidal basins to various parameters related to basin geometry and sediment properties, an extensive numerical analysis of homogeneous soil basins with linear viscoelastic soil behavior was carried out. The parameters and models were selected mainly with reference to the parameter ranges of the literature [24] while considering the characteristics of the physical parameters of the site as specified in the Chinese Seismic Code, and similar works were found in the literature [25; 26; 27]. Homogeneity and viscoelastic behavior were chosen as reference assumptions for the numerical models, which is a common practice in such studies [24]. The surface ground motion was simulated in batch by the finite element software ABAQUS, and the specific analysis process was described in the previous subsection, similar simulation processes were found in the literature [25; 27; 28]. This paper focused on  
Figure 8: Sample amplification process. Figure 6: Illustration of the site of a basin. (**a**) Lower Hutt valley basin in Wellington, New Zealand. (**b**) Lower Var valley basin in Nice, France. Figure 7: Simplified diagram of the standard basin. the amplification characteristics of small and medium-sized basins, which span less than 3000 m. The influence of incident angle and incident wave frequency was not considered in this study. In order to reduce boundary errors, the bedrock was set laterally to 800 m from either side of the basin, and the overall height of the model was unified as 500 m. The range of soil properties in the basin was controlled within a reasonable variation, so as to satisfy the richness of the basin geometry and medium parameters.