Purpose: Rural settlements are a part of Land use and regional planning discussed at the national and regional levels. The subject of the research is to analyze the patterns of the spatial distribution structure of the rural settlements in the western region of Lake Urmia. The study aims to explore the spatial distribution and the relationship and effectiveness of natural foundations on how the spatial structure is formed and to know the factors affecting the spatial distribution of rural settlements in the western region of Urmia Lake.
Methods: The primary data were used in the form of several layers of information, such as the layer of centers of rural settlements in the western region of Urmia Lake, the surface density layer of settlements, the layer of height, slope, hydrographic network, geomorphology, geology, tectonics (faults), Google Earth satellite images and field survey observations. Geostatistics and spatial analysis methods were used in the ArcGIS environment, including various data extraction and transformation techniques, kernel function techniques, geographic distribution measurement techniques, and visual analysis.
Results:  The research results show that the spatial structure of rural settlements of the western region of Urmia Lake does not have a normal distribution and natural balance, and irregularities are observed in the form of clusters and scattered cases of settlements. The findings show that this irregularity is caused by the morphostructure of the spatial distribution of natural factors and foundations, especially the height and geomorphological factors in the region. Fault systems are the most critical factors of morphogenesis, which, in the form of horst (hills and mountains) and graben (pediments) landforms with a north-south trend, play a more influential role in the spatial structure of rural settlements. The results show that the highest concentration is in the grabens of the Urmia and intermountain pediment (74% of settlements) and the scattered pattern in the landforms of the horst with hilly (26%) and mountainous (0.01%).
Conclusion: The spatial distribution structure of rural settlements of the western region of Urmia Lake has a direct inverse relationship with the height factor, and contrary to the increasing trend of the region's height from east to west, the spatial distribution density of rural settlements decreases sharply. The overlaying of the geomorphology layer (landforms) with the centers and the surface density layers of settlements shows that the compound conical cluster pattern is the dominant spatial pattern and the center of gravity (with a density most value of 44.5-62.4). Among the natural foundations, combination factors of fault, height, and geomorphology have the most significant effect on abnormal spatial distribution and the formation of scattered and cone-shaped cluster spatial structures in the rural settlements of the region.