A Micromorphological Analysis of the Neolithic site of Mahtaj, Behbahan Plain

One of the long-lasting discussions concerning early Neolithic sites in the Iranian plateau deals with the issue of seasonal or permanent settlements that is directly related to level of human mobility during this period. It is noteworthy that this time period coincided with earliest signs of sedentary life style and domestication of some species of animal and plants. What kinds of activities were usually focused by the early Neolithic societies? In addition to the normal archaeological finds, understanding the site formation processes -as a new approach- and the kinds of on-site human activities are also increasingly of importance. Most importantly, micromorphological analysis is playing an increasing role in this case. Therefore, to better understand the nature of deposition and sorts of various activities that might have been done in the past, the Late PPN site of Tapeh Mahtaj was examined. The site is located on a natural hillock composed of fine and fertile sediments of the Behbahan plain, south-western Iran, close to the foothill of the Zagros Mountains. The site was briefly excavated in 2015 and as a result, stratigraphic observations attested to the presence of three major occupational phases. However, further information left with analysis of a micromorphological sample that was taken from the north trench-section of the site, where it provided a maximum amount of its deposits. The results of site formations analyses by thin section studies at Tapeh Mahtaj identified several occupational phases as a sequence of human activities. This study revealed living floors that are shown by plastering, infillings, numerous charcoal and bone fragments, face pigments, organic materials and exciting mineral elements such as phosphate. All these findings present the nature of human activities in the Mahtaj site during the time spanning from late 8th to early 7th Millennium BC. It should be noted that this chronological time frame of the site has also recently been suggested by radio-carbon dating, where this time period is archaeologically consisted with the emergence of the initial ceramics across the Near East. This highlights the key role of such micromorphological analyses to track those activities associated with early pottery making. At a site-level, however, one of the most interesting results of the micromorphological analysis is the discovery of a dung pellet in the lowest stage of the site occupation. This shows that the site occupants might have dealt with animal husbandry, presumably goat herding. It is also believed that the site was probably used as seasonal campsite for mobile pastoralists during the late 8th millennium BC. Additionally, the observation through thin sections such as bioturbations, temperature fluctuations effects (clay cracks), and twist flow in deposits by freeze/thaw, diffused iron oxide nodules indicate a short-term seasonal use of the site during the cool, wet periods. Overall, the site formation study at Mahtaj matches with the archaeological evidence such as the low density of archaeological finds and the low volume as well as nature of the deposits remained. These all point to the presence and mechanism of the early occupants of the Behbehan Plain who had intensive interactions with the nearby highland Zagros Mountains.