Luminescence Dating of Relics in Ancient Cities Provides Absolute Dates for Understanding Human-Land Relationships in Qinghai Lake Basin, Northeastern Tibetan Plateau

Manping Sun,Yongjuan Sun,Liqian Xie,Guangliang Hou,Chongyi E,Haicheng Wei,Yongxin Zeng,Ji Xianba

doi:10.3389/feart.2021.701037

Abstract

The study of ancient city sites provides valuable evidence for understanding human-land relationships. Qinghai Lake Basin, on the northeastern Tibetan Plateau, was a key location for economic and cultural exchanges between East and West in ancient China and archaeological surveys have identified the remains of many ancient cities. Although there are relatively good historical records for some ancient cities, their absolute ages are still unclear due to a lack of systematic chronological dating. In this study, OSL dating of ceramic and tile remains from three ancient cities in Qinghai Lake Basin, Xihaijun (XHJGC), Beixiangyang (BXYGC), and Fuxi (FSC), was combined with documentary and paleoclimate evidence to investigate historical human-land relationships. Relics from XHJGC and BXYGC were dated to 0–220 AD, in the Han Dynasty, while tiles from FSC were dated to 120–520 AD, largely corresponding to the Wei Jin Southern and Northern Dynasties. Luminescence ages were generally consistent with dates recorded in historical documents, indicating that the OSL method can be reliably used to date buried tiles in ancient cities on the northeastern Tibetan Plateau. Comparing the dates with paleoclimatic records suggests that the warm and humid climate at c. 2 ka was an important driver of immigration to the region that led to the construction of cities in the Qinghai Lake area during the late Western Han Dynasty. During the Wei Jin Southern and Northern Dynasties (220–589 AD), communication between East and the West flourished, and human activities in the area were strong with the continuation of the war in Central China and Hexi Corridor. Fuxi was largely abandoned in the later Wei Jin Southern and Northern Dynasties, although it was still used intermittently until the Ming Dynasty. Pollen records confirm that humans were extensively engaged in agricultural production in the Qinghai Lake area during the Wei Jin Southern and Northern Dynasties.

Highlights

It has been argued that cities are the product of a certain stage in the development of human society, marking the end of primitive society and the arrival of civilization (Bureau of National Cultural Relics, 1996)
At the beginning of the 4th century AD, the nomadic Tuyuhun occupied the Qinghai Lake area and after they came into contact with agricultural influences via the Silk Road, they began to OSL dating was undertaken on tiles and ceramics from the ancient Qinghai Lake Basin cities of XHJGC, BXYGC, and FSC
The OSL ages of 0–220 AD for XHJGC and BXYGC and 120–520 AD for FSC are consistent with historical documents

Summary

Introduction

It has been argued that cities are the product of a certain stage in the development of human society, marking the end of primitive society and the arrival of civilization (Bureau of National Cultural Relics, 1996). The study of ancient cities can reveal the political, military, economic, and cultural conditions of a region, which is fundamental for understanding the historical development and evolution of human-land relationships (Li, 1995). On the Tibetan Plateau, northeastern Qinghai Province was an important boundary area between nomadic tribes and agricultural regimes during historical periods (Dong et al, 2016). Many wars between ancient agricultural and pastoral regimes in China have been related to climate change, with deterioration of the ecological environment during periods of unfavorable climate conditions leading to social instability (Dong et al, 2016). Frequent wars may have stimulated the construction of a large number of ancient cities on the northeastern QinghaiTibet Plateau; Dong et al (2016) argue that most were initiated for military defense purposes. Documentary evidence and radiocarbon dating suggest that most of the cities were built or repaired during the Han Dynasty (202 BC‒220 AD), Tang Dynasty (618‒907 AD), the Five Dynasties and Ten Kingdoms period (907‒960 AD), the Song Dynasty (960‒1279 AD), and the Ming Dynasty (1368‒1644 AD) (Dong et al, 2016)

Results

Discussion

Conclusion