Studying the Effect of Natural Factors on Spatial Distribution of Sassanid Sites of Darreh Shahr City

Today, the approach of new archeology studies is applying different sciences, especially use of geographic information system (GIS) and sciences such as statistics, and different methods and models of these sciences. By using other scientific methods and tools, the orientation of spaces archeology has largely achieved a correct understanding of issues such as establishment pattern of ancient civilizations and the interactions between humans and environment. Darreh Shahr city in Ilam province is one of the areas where, apart from some scattered references in the content of geographical texts, no purposeful study has been done regarding the presence of Sassanids there. Therefore, in order to fill this historical gap, after conducting archeological studies with the aim of discovering the cultural evidence of the Sassanid presence in this city, 117 monuments were identified. Some researchers believe that the ruins of Seymareh in the south and southwest of the present city of Darreh Shahr during the Sassanid period, and at the center of Mehrjan-e-Ghazq furnace was part of the western part or Khorbaran coast.In this study, for the first time and with respect to environmental elevation, slope, land use, and distance from roads and rivers, the settlement pattern and spatial distribution of Sassanid landscapes of Darreh Shahr are analyzed using descriptive-analytical method and field-library studies. To achieve goals such as locating ancient sites, analysis of settlement patterns and finally, investigating the impact of environmental factors on the formation process and distribution of Sassanid areas, tools such as Geographic Information System (GIS), SPSS software, statistical models such as mean of nearest neighbor, linear regression, correlation coefficient and PCA method were used. The results show that the most important factor affecting the spatial distribution of Sassanid sites in Darreh Shahr is first, the distance from rivers and then, the factors such as altitude and slope of the area. In addition, based on the average nearest neighbor model, the pattern of settlement in the Sassanid areas of this region is almost identical and clustered.