Abstract
This paper presents a summary of a recently conducted geoarchaeological survey in the Susiana plains in southwest Iran. Here, the question of subsequent interaction of human settlements and their riverine landscape of the Greater Susiana region (roughly equivalent to modern Khuzestan) in the Later Village and the Early-historical periods (~ fifth to second millennium BCE) has been chosen as a case study. This study challenges the idea of the cultural expansion from South-Mesopotamia and its direct socio-political involvement in the spatial evolution patterns in Susiana in this timespan. It also offers an alternative interpretation: the riverine landscape and its spatial interaction with the settlement system. It has been suggested that the Later village settlements of Susiana were greatly influenced by the physical changes of the riverine landscape in their spatial development. This paper examines this hypothesis via geoarchaeological methods from the macro-level such as remote sensing to micro-level such as laboratory analysis of sediment logs to address this issue. The results of this study confirm three main points: (i) the westward migration of active watercourses in the mentioned time span; (ii) the direct correlation of this event with the spatial evolution of the studied settlements; and (iii) the overall differences between the neighboring plains of Susiana and south Mesopotamia in their geomorphological response to their fluvial evolution. 
Keywords: Geoarchaeology, Greater Susiana, Riverine Landscape, Later Village Period, Early History, Settlement Patterns.

Introduction
Geoarchaeology has established itself as a decisive means to study the human-environment-interaction in recent years. The use of geo-sciences in archaeology has revived the archaeological discourse regarding entanglement and niche construction theory, especially in the Near Eastern Archaeology. Yet, the Iranian archaeology lags behind in this matter. This paper contributes to this issue and aims to demonstrate the huge potential of geoarchaeological investigations in the Iranian archaeology.
The Susiana plains are an archaeologically rich region and suitable to examine the human-environment interaction in pre- and early history. The author has carried out a geoarchaeological survey in 2014 in this region to address this issue. The analyzed results have been published in detail (Rashidian 2020) and are briefly presented here.
Archaeological evidence of this region indicates a spatial change in the settlement patterns in the mentioned periods, including the abandonment of central settlements in the eastern plains and foundation of new settlements in the western plains (Adams 1962; Johnson 1973; Moghaddam 2012a). The common interpretation of this phenomenon related this spatial change to a socio-cultural or even political force from the South-Mesopotamian center, especially during the end of Ubaid and the beginning of the Uruk periods (Algaze 2005; 2008). This hypothesis has been discussed within the framework of the world-systems and criticized for decades, especially due to recent archaeological projects from modern Syria and neighboring regions. By integrating geoarchaeological investigations, these studies have shown that the spatial evolution of the settlements in the so-called periphery regions has been endogenic and not imported from Mesopotamia (McMahon & Crawford 2010; Ur et al. 2007). They have also offered alternative hypotheses for this phenomenon. Yet, for the Susiana region, this has remained the common hypothesis, despite occasional critic and speculation (Alizadeh et al. 2004; Moghaddam 2012a).
This has been the main focus of the present study, which examines two aspects: (i) There are strong indications of a westwards-migration of palaeo-rivers in the Mid-Holocene period, as mentioned by others (Kouchoukos 1999; Lees & Falcon 1952). (ii) In addition to a shift in watercourses and riverbed, such a fluvial change would affect the entire landscape immensely, for example, by changes in the surface slope, sediment freight, and soil characteristics. This probable landscape shift shall be comprehended in focusing on ten archaeologically known settlements (Abu Fanduweh, Abu Chizan, Band-e Qir, Chogha Mish, Dar Khazineh, Dehno, Haft Tappeh, Samirat, Sanjar, Sharafabad) in respect to the watercourses Dez, Karkheh, Karun, and their tributaries. During the here presented  geoarchaeological survey, hundreds of soil profiles, as well as fifty-one subsurface cores, have been documented in the environ of these settlements in the riverine landscape. 

Discussion
The sedimentological laboratory analysis of the documented horizons (surface and sub-surface) confirmed the large-scale migration of the rivers towards the west of the plain, which correlates with the spatial shift in the studied settlements, both in macro- and micro-level (in the region and within the settlements themselves). 
Furthermore, it was shown that not the large rivers, but the smaller rivulets had been the source of water for these settlements, despite prior speculation. Following the westwards fluvial migration, these rivulets have been cut off the hydrologic regime of the region and largely covered by recent sediments in the third and second millennium BCE. A number of them have been revived and integrated into the new canal network in the Early historical and Late Antiquity. Relative and absolute dating, based on material culture in situ and optically stimulated luminescence of sand in bulk samples respectively, have provided a dating framework for the presented geodata.
In general terms, focusing on geomorphological elements of the landscape such as slope, soil characteristics, and sedimentary regime has proved beneficial to examine the spatial evolution of prehistoric settlements. Susiana as a dynamic landscape has changed considerably in response to the fluvial regime change and extensive human impact. This has been attested in the presented geodata in this period. An intensification of the mentioned event is also confirmed for the later period, where the human impact has largely escalated due to centralized and planned developments of well established political entities From the Neo-Elamite to the Sasanian period. 

Conclusion
This study provided a range of results concerning the hypothesis and the relevant settlements. Three main points are summarized here: 
(i) The westward migration of Susiana’s active watercourses during the fifth to second millennium BCE has been confirmed using a combination of remote sensing, sedimentary analysis of cores, laboratory analysis of sediment horizons, and methods of indirect and absolute dating.  
(ii) A correlation in spatial evolution of settlement patterns with this fluvial development has been confirmed, based on available archaeological record of the ten mentioned settlements. This spatial correlation is attested both in macro- and micro-level. In this regard, a general tendency of settlements towards the western parts of the plain can be confirmed for this timespan. Furthermore, this has been attested in the spatial evolution within the settlements and it seems that some were following their migrating watercourses, and others have been abandoned entirely.
(iii) The results of this analysis also show the stark difference between the flat landscape of South-Mesopotamia with its large riverbeds as primary geo-elements in the west, and the softly sloped landscape of Susiana with its numerous rivulets and narrow floodplains surrounded by ridges and anticlines in the east. It is safe to assume that these starkly different landscapes have brought about equally different settlement patterns. Therefore, the settlement evolution of Susiana must be considered endogenic and studied in the framework of its landscape.
A detailed account of the presented study has been recently published (Rashidian 2020). A few case studies are also subject of English papers (Rashidian 2017; 2018; in press). The author hopes that this summary in Persian can contribute to the present discourse and encourage active members of the Iranian Archaeology to integrate geoarchaeological investigations into their projects. This is the only way towards further establishing an internationally acclaimed place for the Iranian archaeology.