Geo-Archaeology of West Susiana Plain with an Analysis of Hydraulic Structures

Geo-archaeology arises from the integration of methods and abilities of archeology and geomorphology. Evidences suggest that during the history of the earth, climatic conditions have undergone numerous changes in geographic characteristics, including geomorphic ones. Understanding the geomorphic phenomena and its effects on ancient habitats help in identifying human habitation patterns and therefore, managing archaeological heritages in a regional scale. Susiana plain in the north of Khuzestan province has been the longest site of the first and most extensive archaeological research in Iran. Susa, the foundation of the first cultural succession framework, has been introduced from prehistoric periods in southwestern of Iran. Based on the surveys and extensive excavations in Khuzestan, different sites have been identified with long-term occupancies, which in some way illuminate the settlement system of different periods of life in this area. Over a hundred years of excavation in Susa, the signs of settlements and communities have been identified, which prove that these settlements have begun since the middle of the 5th millennium BC, and continued steadily until the seventh century AH. Generally, human and natural changes can be the cause of the weakening of the settlements at any time period. Now, the question is which of these factors has influenced the weakening of the settlements of the western Susiana plain and what process has taken place? The purpose of this research is to investigate the role of the factors affecting these settlements. Susiana plain, as one of the most important human origins in the Middle East, is of great importance to those interested in the natural and ancient sciences. Geo-archaeological studies, and especially the use of geomorphological techniques to understand the pattern of human habitats, can be an effective step towards making the history of civilization clearer in this region, and in Iran. The methods used in this study were application of corona satellite images, field observations and luminescence optical lens experiments. Overall, the survey of the environment, review the totality of settlements and water resources, as a criterion for field deployments, have been used in this study. Therefore, the separation of historic or prehistoric periods is not so significant. Although the role of human factors in undermining certain important settlements is undeniable, but in the vastness of a plain with hundreds of scattered settlements, a greater reason is required. In addition, there is not enough evidence available from anthropologists about human factors yet. If we consider the importance of water in human societies and throughout the human history along with the environmental changes detailed in the discussion, it can be assumed that the natural changes were the main factor in undermining or destroying the settlements of the western Susiana plain. The overall results show that, contrary to the assumptions, the Dez River plays an important role in the population deployments of the western Susiana plain, which has been abandoned after geomorphologic changes in the bed and as a result of the lowering of the water level, declining the settlements of the plain. Eventually, after an indefinite period of time, with the construction of the Harmushi channel from Karkheh and the expansion of its branches, the settlements were gradually reformed in the western part of Susiana plain.