Chinese geologists claim they have strata and paleontology proof that the bulk of southern China was beneath the sea 350 million to 410 million years ago.

This was the result of three-year research by the Nanjing Institute of Geology and Palaeontology under the Chinese Academy of Sciences.

Based on the latest paleontological evidence, scientists have concluded that most parts of the South China Plate – spanning today’s Yunnan, Guizhou, Sichuan, Hunan, Hubei, Zhejiang, Jiangxi, Fujian and Guangdong provinces as well as even northern Vietnam – was indeed inundated by seawater in ancient times.

The researchers discovered a fossil, in east China’s Jiangxi province, of a typical plant that lived in shallow waters dating back 410 million years. This indicates the province was submerged under shallow seawater at that time.

About 410 million years ago, China’s the coastline was in today’s central  Guangxi, southern Hunan and northern Vietnam.

A further study of plant fossils unearthed from more than 50 areas across the South China Plate revealed that the coastline on the plate gradually advanced eastwards ever since, as the ocean retreated due to tectonic movement and the rise of the Eurasian Plate.

The findings were published in the November issue of the scientific journal Palaeogeography, Palaeoclimatology, Palaeoecology.

The discovery that southern China was submerged may also lend more support to the theory that some cities in southern China may be sitting on massive oil and gas reservoirs.

A preliminary estimate by the geological survey unit of the Chinese Ministry of Land and Natural Resources put the potential oil reserves in the affluent Pearl River Delta near Hong Kong and Macau in southern Guangdong at 8 billion tons, state broadcaster China Central Television reported in August 2017.

To put the figure in perspective, China consumed 556 million tons of petroleum in 2016. There have been proved reserves in Foshan and Huizhou in the region.

Officials with the geological survey unit suggest further surveys be carried out in the region to ascertain the size of the reserves, but they caution against immediate exploitation due to environmental concerns.