Abstract

The Suối Bàng coal-bearing formation is composed of two parts: the lower containing marine fauna of Norian age and the upper of subcontinental facies containing coal with many beds yielding plant remains of the Hòn Gai Flora of Rhaetian age. For convenient to the geological mapping at large scale and the clear expression of the mineral-bearing part on the map, this formation is proposed by the authors to be upgraded into a group with 2 formations, namely: Suối Lôi of marine facies of Norian age, and Mường Vọ of subcontinental coal-bearing facies of Rhaetian age.