Beipiao Fm

It was named by Tan Xichou as the “Beipiao System” in 1931. The naming section is located in the Beipiao Coal Mine, with its reference section being seated in the area of No. 4 quarry of Sanbao, Beipiao City till the vicinity of the Quanjia Village.

Synonym:（北票组）

Lower part is composed chiefly of black, dark-grey and grey-white sandstone, sandy shale and shale, intercalated with sandy conglomerate and a good many of coal beds, yielding abundant plant fossils, with a thickness of about 300-350 m. Upper part is of grey-black and black massive shale, sandy shale and sandstone, intercalated with thin coal beds, yielding plant, spore-pollen and insect fossils, with a thickness of about 300-400 m. The total thickness of the formation reaches to 1312 m.

There are found more than 50 species of plant fossils in the formation, belonging to an early-stage assemblage of the Coniopteris-Phoenicopsis flora; while spore-pollen fossils are found to occur only in its upper part, and being represented by Osmundacidites-Chordasporites assemblage, and with the Yangshugou Coal Mine in Kazuo County being characterized by the occurrence of the Marattisporites-Osmundacidites-Chorodasporites assemblage. From among the insect fossils there tend to occur Rhipidoblattina longa. R. mayingziensis, Euryblattula beipiaoensis, E. chaoyangensis and Taublatta yangshugouensis.

The Formation belongs to fluvial and lacustrine deposits.