Laodaomiaogou Fm

The type section of Laodaomiaogou Formation is the Line No. 27 section of the Xiaoxilin Lead-Zinc Mine, Jinlin District, Yichun City, Heilongjiang Province. It is located at the Lead-Zinc Mine Area (129°08’30”E, 47°23’30”N), about 22 km west of the seat of Jinlin District. The formation is over 593 m thick in the type section. The Laodaomiaogou Formation was first published by Heilongjiang Bureau of Geology and Mineral Resources (1993). The name is derived from Laodaomiaogou Village, Jinlin District, Yichun City, central Heilongjiang Province. The name was originally appeared in a 1965 unpublished report by Zhao Tongji et al. from the Third Geological Team of Heilongjiang Bureau of Geology.

Synonym: （老道庙沟组）

The Laodaomiaogou Formation is a fine clastic sequence, consisting of siltstone, silty shale, and gravel-bearing fine sandstone. In the type section, the formation is divided into three beds, from bottom up: 1, grey, gravel-bearing fine sandstone with interbeds of thin-bedded fine sandstone (over 36 m); 2, dark grey, grey micro-layered to thin-bedded fine sandstone (163 m); 3, purplish grey to light grey silty shale and dark grey, purplish grey siltstone, increasing muddy content upwards in section, and the rocks are skarnization in part (394 m).

No fossils has been found from the formation