Genkou Gr

Named by Li Yuyao and Zhu Sen in 1934. The named section is located in Burgundy Village at the junction of Guangdong Lechang and Hunan Yizhang; the reference section is located in a comprehensive section in the Gaoming-Fuwan area of Guangdong. The original Genkou Gr refers to the Mesozoic coal-bearing strata discovered by Zhu Tinghu in Burgundy Village in 1929, which is stratified between the Jurassic Jinji Formation and Carboniferous tuffs.

Synonym: In 1973, the Southern Coal Research Team of the Academy of Geological Sciences called the Burgundian Group, which includes the Hongweikeng, Xiaoshui and Niuguodun sections from the bottom up, and is dated to the Late Triassic. 1988, the regional geological record of Guangdong Province further clarified that the western part of Guangdong is the Xiaoyunwu Mountain Group, and the northern, central and eastern parts of Guangdong are called the Burgundian Group. In 1988, the regional geological journal of Guangdong Province further clarified that the western part of Guangdong is the Little Yunwu Mountain Group, the northern part of Guangdong, the central part of Guangdong and the eastern part of Guangdong are called the Burgundian Group, which is divided into the Hongwei Keng Fm (Hongweikeng Fm), the Xiaoshui Fm and the Toumuchong Fm from the bottom up, and the age is Late Triassic.

It is mainly composed of conglomerate, mixed sandstone, siltstone, sandy shale interspersed with rhodochrosite and thin coal. The group is divided into the Hongweikeng Fm, Xiaoshui Fm and Toumuchong Fm from the bottom up. In the lower part of the group (Hongweikeng Fm), medium and fine-grained quartz sandstone and siltstone are mainly interspersed with shale, carbonaceous shale and coal seam; the lower part is miscellaneous conglomerate; the thickness varies greatly from 45 to 480 m; Xiaoshui Fm (middle formation), dominated by gray and gray-black siltstone and shale, interspersed with fine-grained sandstone, carbonaceous shale and coal seams, locally interspersed with marl, rich in rhodochrosite lenses; 80 m thick; The Toumuchong Fm (uppermost formation), consisting of medium and fine-grained quartz sandstone, siltstone, siltstone shale intercalated with carbonaceous shale and coal seams, with conglomerate and conglomerate-bearing sandstone locally, is a coal-bearing clastic rock section with a sea-receding sequence of sea-land intersection; 80-160 m thick

Hongweikeng Fm produces the bivalve Bakevelloides-Cuneigervillia assemblage. Xiaoshui Fm contains Palaeophorus-Oxytoma-Tosapecten assemblage. Toumuchong Fm contains the bivalve Jiangxiella-Modiolus combination, with plants of the southern type Ptilozamites-Lepidopteris flora.

It is built of interfacial clastic rocks between land and sea.