۸.۲ka Climatic Event and the Problem of the Formation of Pottery Neolithic Settlements in the Southeast of the Caspian Sea

The Caspian Sea, the largest inland lake in the world, witnessed many transgressions and regressions during the Late Quaternary period. Khazarian, Early Khvalynian, Late Khvalynian, and Neo-Caspian transgressions, and Atelian, Enotaevkian, and Mangyshlak regressions are the main sea level change periods. During the ۸۴۰۰ to ۷۷۱۰ BP, another regression happened, in which the sea level reached -۴۲; the ۸.۲ka climate event probably was the cause of this regression. This change is characterized by the collapse and abandonment of large sites such as Jericho and the Ain Ghazal phase I in the southern Levant, migration on a large scale, and continued settlement in some regions in Southwest Asia. However, this climate period in the eastern region of Mazandaran seems to have had a different effect compared to other regions of Southwest Asia; due to the change in Dinocyst assemblage during this period, a major change in Caspian Sea conditions is recognizable. The existence of numerous shrub species at the beginning of the Holocene (۱۱.۵-۸.۴ ka), despite the relatively dry conditions that continued until ۸۴۰۰ BP, delayed the growth of trees in the region. However, the change of vegetation in the region from steppe species to shrub species indicates an improvement in the climate in the Early Holocene. The transition to the Middle Holocene and the change from dry to warm and wet conditions and from shrub vegetation to a significant increase in trees, based on pollen evidence, is contemporary with the vast increase of human communities in this region; The settlements, in addition to Caves, are also seen in the plains and highlands at ۱۰۰۰m or higher above sea level. According to archaeological excavations in the two Pottery Neolithic sites, which belong to about ۸۵۰۰-۷۷۰۰ BP, human settlements in the Neka and Behshahr plains, appeared on the Late Khvalynian deposits. The current study indicates there is a connection between the regression of the Caspian Sea at ۸۴۰۰-۷۷۰۰ BP, the ۸.۲ka climate event, and human settlement pattern in the eastern Mazandaran during the ۸۵۰۰-۷۷۰۰ BP and Pottery Neolithic period.

کلیدواژه ها:

Transgressions and Regressions ، Caspian Sea ، ۸.۲ka Event ، Neolithic ، Holocene