... ,maybelowerFrasnianwithConodontsPa.transitans and some Stromatoporoids.The Tan Lap Formation co nsists mainly ofsandstone containing landplant remains ofLepidodendropsis, and is restrictively exposed in some areasofChiLang and BacSondistricts(Lang ... VuKhuc,BuiPhuMy(Ed.),Geologyof Viet Nam. Vol.I.Stratigraphy,VietnamGeneralDepartmentofGeology and Mining,Hanoi,19 90 (in Vietnamese).[23] WangHong‐ch enetal.,Atlasofthepalaeogeographyof China, Cartographic ... Science and Technology PublishingHouse,Hanoi,1977 (in Vietnamese).[17] Pham Dinh Long (Ed.), Geological and Mineralresourcesmap1:200,000,ChinhSi‐LongTansheet,Vietnam...