Zhenzhumen Fm
Type Locality and Naming
Southernmost Jilin. The Zhenzhumen Fm was named by the Southern Jilin Party of Regional Geological Survey, Changchun College of Geological Prospecting in 1960. The naming section is in Taiping Township, Hunjiang City, Jilin Province. Lower-Middle (2 of 5) formation in Laoling Gr.
Synonym: （珍珠门组）
Lithology and Thickness
It is dominated by dolomitic marble, followed by brecciated marble and banded marble, occasionally accompanied with sericite chlorite phyllite and schist (chlorite-schist, calcareous sericite schist) and hematite bands. A phosphate ore bed is seen on the north bank of Hunjiang River in Fe-P bearing dolomitic marble in the upper part of the formation. The formation is 2377 m thick.
Relationships and Distribution
Lower contact
It is in conformable contact with the underlying Dataishan Fm.
Upper contact
It is in conformable contact with the overlying Huashan Fm.
Regional extent
Southernmost Jilin. The Zhenzhumen Fm distributed on north bank of Hunjiang River is also dominated by dolomitic marble, where it is stable and has great thickness, in general ranging from 800 m to 1200 m, even up to 2440 m thick locally. It possesses peculiar and strata-bound phosphorites, uranium, talc, lead-zinc and pyrite deposits, for example the Yaolin talc ore body.
GeoJSON
Fossils
Stromatolites in the middle and upper marble are Conophyton cylindricum etc.
Age
Depositional setting
Additional Information