GIS-BASED URBAN GEOMORPHOLOGICAL ANALYSIS OF THE SULAIMANIA CITY, KURDISTAN REGION, NE IRAQ

Abstract

Sulaimania City, is located in, the northeastern part of Kurdistan Region of Iraq within the series of Zagros Mountains. It is situated within the High Folded and Imbricate zones, in an intermontane depression surrounded from the east by the Azmar Mountain and from the north by the Pira Migrun Mountain, and from the southwest by the Qaradagh Mountain range. This situation makes the Sulaimania City an excellent model for a big mountainous city in Iraq with geologic and geomorphologic environment greatly influencing the city growth modes. Digital Elevation Model (DEM), satellite images, different kinds of maps, in addition to field observations of the city and surrounding areas are used to investigate the impact of the geomorphologic factors on the city expansion pattern. A set of digital maps are constructed to show the interaction between the city urban growth pattern with: i) topography and geologic features, ii) geomorphic units and overall landscape style, iii) slope type and hazards, iv) lineaments density, v) flood hazards, and (vi) drainage system. All the maps are displayed in a GIS environment and some of them are made for different periods to show the city growth. Three basic stages of city growth were inferred and mapped to show the relation between city expansion and physical environment components and hazards. The results of this work show that the circular growth patterns of the Sulaimania City at early stages (1925 – 1973) prefer growth over areas covered by the fluvio-denudational landscape. Progressive stages of expansion move over flood-plains, alluvial fans margins as well as rolling hills areas. Growth at early stages avoids sloping or elevated areas with high drainage intensity and lineaments density, as well as, areas with high flooding risk. Recent explosive expansion pattern (after 1973) shows more irregular shapes with effective expansion over slopping areas, which are covered by Quaternary depression fills or soft sediments of the older geologic units. These areas are located along the northwest, northeast and southeastern directions over mountain's lower slopes, badlands, and rugged rocky terrains of the city- suburban areas are following major roads entering the city.