Shanglan Fm

The type section is located at Shanglan of eastern Fule Village, Jianchuan Country, Yunnan. It was named by Survey Team of the 1st District of Yunnan Geological Bureau in 1974, which used to be named as Weixi Gr by Ren Jishun and Qu Jingchuan in 1966. Based on the Jiangweitang-Masuqing type section in Jianchuan area, Ren Jishun and Qu Jingchuan used to name the Middle Triassic strata as Weixi Group in 1966. In 1974, In 1974, the Survey Team of the 1st District of Yunnan Geological Bureau considered that the structure is complex and stratigraphic sequence was not clear in this type section, so it could not represent the Middle Triassic strata in the Jianchuan-Heihuijiang area. Therefore, the Shanglan Fm was named to represent the Anisian clastic rocks of the Middle Triassic distributed in the west of Jianchuan-Heihuijiang area in Yunnan.

Synonym:

Lower part of this formation is mainly composed of grayish-green, grayish-black slate, sandstone, siltstone and shale intercalated with argillaceous banded limestone, and quartz conglomerate can be found at the bottom intercalated with purplish red layer, slightly metamorphic rocks, 2034 m thick. Upper part of this formation is mainly composed of grayish-green slate, siltstone interbedded with thin-bedded limestone, 1900 m thick.

It yields bivalves including Costatoria goldfussi mansuyi, Entolium liscaviensis, E. discites, Gervillia cf. albertii, “Gervilia” yunnanensis, Plagiostoma beyrichi, Neoschizodus laevigata, Hoernesia socialis, and ammonoids, gastropods, seaweed, and plants.

It is interpreted as a coastal sea and shallow sea.