A New Understanding on South China Permian Coal-bearing Strata and Coal Accumulation Regularity

The Longtan Formation was originally thought to belong to the Late Permian, but this study reveals that the lower part of this formation belongs to the Middle Permian. The study proposes the corresponding chronostratigraphic boundary and new schemes for the correlation of geological sections. Based on these schemes a new understanding on the accumulation regularity of Permian coal measures in South China is reached.