## 2 Data and Methods
### Data Acquisition  
This study collected data on various period sites in Sichuan Province, including 476 from the Stone Age, 347 from the Shang to Spring and Autumn periods, and 261 from the Warring States period. The site data were compiled from the Atlas of Chinese Cultural Relics: Sichuan Volume, and related archaeological survey reports (Table 1). For sites without coordinates in the reports, latitude and longitude were obtained using the Baidu Coordinate Picker and spatially located using ArcMap 10.8. The study comprehensively covers and efficiently integrates information from archaeological reports across multiple periods, including all publicly available data published after the Atlas of Chinese Cultural Relics: Sichuan Volume. The DEM data and geomorphological data were obtained from the NASA Earthdata ([[https://www.earthdata.nasa.gov](https://www.earthdata.nasa.gov)]([https://www.earthdata.nasa.gov](https://www.earthdata.nasa.gov)), accessed on 30 November 2013),  
Figure 1: Overview of Chengdu Plain. specifically the GDEM V3 30 M resolution elevation dataset. Elevation and slope data for the study area were extracted from the DEM. The distribution of sites in Sichuan Province is shown in Figure 2, with blue, red, and yellow representing Stone Age, Shang to Spring and Autumn periods, and Warring States period sites, respectively. The map was created using the standard topographic map of Sichuan Province issued by the Sichuan Bureau of Surveying and Mapping. In addition, the number of site points in each geomorphological type was statistically analyzed, and the results are presented in Table 2. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Index Number** & **Source of Information** & **Number of Sites** & **City and Area of the Sites** & **Name and Excavation** \\  & & & & **Year of Sites** \\ \hline \multirow{4}{*}{1} & _Nenly Discovered_ & & & Diao Shanzui site, Hehua \\  & _Paleolithic Sites in the_ & 12 & Meishan City & Village site, Jigong Reservoir site, Jie Xin Chang site, etc. \\  & _Southern Chengdu Plain_ & & & 2021. \\ \hline \multirow{4}{*}{2} & _A Brief Report on the_ & & & \\  & _Archaeological Survey of_ & & & \\  & _Pre-Qin Period Sites in the_ & & & \\  & _Middle Reaches of the_ & 9 & Nanchong City, 1,650,000 & Ming Jiazui site, Xianba site, \\  & _Jialing River (Peng’an to_ & & square meters & 2016-2017. \\  & _Nanchong Section)_ & & & \\ \hline \multirow{4}{*}{3} & _A Brief Report on the_ & & & \\  & _Archaeological Survey of_ & 4 & Liangshan Yi Autonomous & Dagou Liangzi site, Guan Shan (Daozuo Miao) \\  & _the Yanyuan Basin in 2015_ & & kilometers & site, Panja Ba (Gaoyanzi) \\  & _On the Hopeful Fields: New_ & & & \\  & _Advances in Archaeological_ & & & \\  & _Discoveries and Research in_ & & & \\  & _the Mitijans_ & 9 & Aba Tibetan and Qiang & District, Chengdu City, Dongyu Village site, \\  & _Region—Centered on the_ & & Autonomous Prefecture & Gaoshan City East site, etc. \\  & _Fieldwork of 2014_ & & & \\ \hline \multirow{4}{*}{5} & _A Brief Report on the_ & & & \\  & _Archaeological Survey of_ & & & \\  & _Late Noolithic to_ & & & \\  & _Shang-Zhou Period Sites_ & & & \\  & _along the North Extension_ & & & \\  & _of Tianfu Avenue (Deyang_ & & \\  & _Section) in Sichuan_ & & & \\ \hline \multirow{4}{*}{6} & _New Achievements in_ & & & \\  & _Archaeological Survey,_ & & & \\  & _Exploration, and Trial_ & & & \\  & _Exaxation by the Sichuan_ & & & \\  & _Provincial Institute of_ & & & \\  & _Cultural Relics and_ & & & \\  & _Archaeology in 2006_ & & & \\ \hline \multirow{4}{*}{7} & _Walking in the Fields: A_ & & & \\  & _Glimpse of Archaeological_ & & & \\  & _Work in the Minjiang River_ & & & \\  & _Basin in 2016_ & & & \\  & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Basic information of the heritage sites derived from archaeological survey reports and literature.