Hunchun Fm

The reference section is located in well No. 749 of the Hunchun coal field, Jilin. Named by the Hunchun coal measures by the 203 Party of the Jilin coal field in 1959.

The Hunchun Formation may be divided into two members, 950 m thick. Lower member is distributed at Luotuohezi, Chedarengou and Miaoling, as well as in the area south of Banshigou, with a total thickness <450 m. The lithofacies varies greatly. At Luotuohezi the main lithology is conglomerate, sandy conglomerate and shale, locally intercalated with minable coal beds and carbonaceous shale, with a thickness of 150–300 m; in the Miaoling area sandstone and shale are predominant and next come conglomerate and 2–3 minable coal beds (inferior coal), with a thickness of 70 m; in the eastern part of Taiyangtun the formation is composed mainly of sandy shale with thin coal beds and carbonaceous shale, 30–80 m thick. Upper member, <500 m thick, is distributed at Sandaoling, in the south of the Hunchun River, at Banshigou and west of Miaoling, and better developed in Sandaoling, where the lithology includes gray to grayish white conglomerate, sandstone, fine sandstone, sandy shale and shale with coal beds and locally conglomerate or sandy conglomerate is well developed.

There are 21 coal beds, of which there are about 12 minable coal beds. The lower member contains sporopollen such as Ulmaceae, Juglans and Magnolia. The upper member contains the plants Sequoia, Fagus and Zelkova, whose aspects are close to those of the Fushun flora.