Tumenling Fm

The type section is located in the Tumen Ridge of Wuchang City, Heilongjiang Province, and the reference section is situated in the Shenzhu area of Tieli City. It was named by Zheng Guangyuan et al., in 1964, and was cited officially by the Compiling Group for the Regional Stratigraphic Chart of Heilongjiang Province (1979).

Clastics. Representing a suite of very thick clastic-rock deposits. Lower member is represented by the Tumenling section of Wuchang City, and is composed of grey feldspar-rich sandstone, siltstone and black-grey slate, intercalated with grey-white siliceous rocks, marl and limestone lenses, with a thickness of 1055 m. Upper member is represented by the Shenshu Mt.-section of Tieli City, and is composed of grey-black conglomerate, sandy conglomerate, carbonaceous slate and green silicified limestone, with a thickness of over 1000 m. There are developed faults over the region, and for this reason no complete tops and bases of the above-mentioned members have been found in many cases, and their stratigraphic sequences were determined by inferring the horizons of the marine animal fossil assemblage concerned. In the area of the Shifa Village the formation and its underlying Yuquan Fm are continuous deposits, with a total thickness of over 2055 m.

Both of the two members yield abundant brachiopod fossils, as well as a small amount of coral, bivalve and bryozoan fossils. The Lower member yields such brachiopods as Waagenites, Liosotella, Paraleptodus, Spirierella salteri, Actinoconchus; while the Upper member yield such brachiopods as Chonetes schlagintweiti, Licharewia neosibirica, and bivalves represented by Aviculopecten kunlunensis, belonging to the Yangsingian Epoch. In the Tumen Ridge, Shenshu Mt. and the Jianshan River of Yichun City the formation yields such plant fossils (phytolites) as Noeggerathiopsis.

It is interpreted as largely of marine and littoral-facies deposits, locally of paralic-facies deposits.