Scientists succeeded up to a year (or even season) to date the construction of the fortress of Por-Bajin in Tuva. For this, they used a new method of combining radiocarbon analysis and dendrochronology, and taking into account the so-called event Miyake. The article published in the journal Proceedings of the National Academy of Sciences.
Por-Bajin fortress occupying an entire island in lake Tere-Khol in the South of Tuva, near the border with Mongolia. Archaeologists attribute it to the Uyghur Kaganate, which in the VIII–IX centuries, encompassed present-day Mongolia and a large part of southern Siberia.
For the lifetime of the Uyghur Khaganate have one of the so-called events Miyake. In 2012 a group of Japanese scientists, led by Fusa Miyake, analyzing the content of radioactive carbon-14 in the annual rings of Japanese cedar, found a sharp jump in this indicator in the year 775. In the most common, but not standard version, it is the result of extremely powerful solar flares. Subsequent studies confirmed that the same elevated levels of carbon-14 in the annual rings of trees 775 year is observed in other parts of the world, and also revealed several similar events throughout the first Millennium of our era.
For Dating Pore-bagina group of scientists led by Margo Cates (Margot Kuitems), University of Groningen, applied method considering the events Miyake. The researchers conducted radiocarbon analysis of 20 samples of logs, the Pore-bayna and found a ring with a high content of carbon-14, the relevant indicators of the 775 event Miyake year. After that, it was enough to count the rings, accrued on top of this to get a year when the tree was cut down. Por-Bajin was built with local building material — larch, growing in abundance on the shores of Thera-hole. From this, scientists concluded that the tree was cut down specifically for the construction site and dried during the summer.
The researchers came to the conclusion that Por-Bajin was built in the year 777. Uyghur Khagan at this time, Bogu was proclaimed the state religion of the khanate Manichaeism. Group Kates suggests that Por-Bajin was built as a Manichaean monastery. Already in the year 779 Bogu died as a result antipanicescoe uprising.
Previously, we wrote about how astronomers were able for the cuneiform records of Assyrian astrologers VII century BC to determine the flash of solar activity. Scientists were able to determine three mentions, which roughly coincided with the results of isotope analysis of tree rings and point to the powerful outbreak in the year 660 BC.