# Implications for Paleontological Heritage Conservation:
## 3 Results
### Some Potential Factors of the Distribution of Fossil Sites
#### 3.2.1 Topography  
Physical geography is one of the factors influencing the distribution of fossil sites, especially the topographical factors. In this study, we downloaded for free the DEM data of SRTM DEM 90 m based on the spatial location of Shandong province, then extracted the elevation values with ArcGIS 10.8.1 and coupled and overlaid them with the fossil sites in Shandong Province by QGIS 3.34 (Figure 5). The results show that the fossil sites are mainly distributed in mountainous or hills areas with higher elevation in Shandong Province. The central mountain area and peninsula hilly area of Shandong Province are the primary fossil site clusterings, with most of the fossil sites clustered along Mount Tai, Mount Lu, and Mount Yi in the central part of the province and the Mount Meng in the southeast, as well as along the hilly area in the east and northeast. In Figure 5, there are 39 fossil sites in Shandong Province with elevations below 100 m, accounting for 29.32% of the total; 11 fossil sites are above 500 m, accounting for only 8.28% of the total; the others are in these mountainous and hilly areas within the range of 100-500 m elevations, accounting for only 62.4% of the total (Table 4).  
Figure 4: Map of the kernel density distribution of fossil sites in Shandong Province.  
Shandong Province has some raised mountains in the central and southeast, low-lying and flat plains in the southwest and northwest, and undulating hills in the east [23,40]. The area below 100 m accounts for 71.01% of the total area, mainly distributed in the west and north of Shandong Province. The area of 100-200 m accounted for 16.20%, mainly distributed in the eastern region. The area of 200-500 m accounted for 11.53%, mainly distributed in the southwest and eastern regions of Shandong Province. The area above 500 m accounted for only 1.26%, mainly distributed in central Shandong Province [40].  
The natural topography of these mountainous and hilly areas is a repository conducive to the long-term preservation of fossil sites. Its distribution trend is fewer fossil sites in the lower elevations of Shandong Province, while there are more fossil sites in the relatively higher elevations. The areas with an elevation of over 100 m account for 28.99% of the total area, but 70.68% of the fossil sites have been discovered in these areas. Generally, mountainous and hilly areas are the only environments where early strata can be exposed,  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Elevation/m**} & \multicolumn{2}{c}{**Fossil Sites**} & \multicolumn{2}{c}{**Land of Shandong Province**} \\ \cline{2-5}  & **Number of Sites** & **Proportion/\%** & **Land Area/km\({}^{2}\)** & **Proportion/\%** \\ \hline \([0,100)\) & 39 & 29.32 & \(11.23\times 10^{4}\) & 71.01 \\ \([100,200)\) & 33 & 24.81 & \(2.56\times 10^{4}\) & 16.20 \\ \([200,300)\) & 33 & 24.81 & \(0.91\times 10^{4}\) & 5.77 \\ \([300,400)\) & 13 & 9.77 & \(0.61\times 10^{4}\) & 3.84 \\ \([400,500)\) & 4 & 3.01 & \(0.30\times 10^{4}\) & 1.92 \\ \(\geq\)500 & 11 & 8.28 & \(0.20\times 10^{4}\) & 1.26 \\ \hline \hline \end{tabular}  
* Square brackets denote closed intervals, including the endpoints, while round brackets indicate open intervals, excluding the endpoints—the same as below.  
\end{table}
Table 4: Elevation statistics of fossil sites and land in Shandong Province.  
Figure 5: Association map of fossil sites and topography in Shandong Province.  
representing optimal conditions for fossil preservation. Moreover, mountainous and hilly areas are where erosion is actively breaking up the fastest; this is also more likely to expose fossils at the surface so people can access them. In addition, most low-lying areas are covered by unconsolidated fluvial or alluvial sediments, which have limited potential for fossil preservation, and plants and animals remaining in such recent sediments probably have not yet undergone fossilization.