Dalizi Fm
Type Locality and Naming
Southernmost Jilin. The Dalizi Fm was named by the Southern Jilin Party of Regional Geological Survey, Changchun College of Geological Exploration in 1960. The type section is in the Iron Deposit Site, in Dalizi Township, Hunjiang City, Jilin Province. Uppermost (5 of 5) formation in Laoling Gr.
Synonym: （大栗子组）
Lithology and Thickness
In general, the formation is dominated by phyllite, sandwiched with limestone. The formation is subdivided into a lower and an upper subformation, according to its sedimentary cycle and ore content. Lower subformation (H1-H4 members) is composed of blue-grey phyllite, dolomitic marble and saccharoid marble. The ore is dominated by siderite, followed by hematite and Mn-bearing magnetite. It yields also stromatolites, as Colonella. Upper subformation (H5-H7 members) is mainly brown phyllite, and the ore is dominated by hematite. Every member bear iron ore of Dalizi type, and the main ore deposits occur in the H4-H5 members. The formation is 5810 m thick.
Relationships and Distribution
Lower contact
The base of the formation is in conformable contact with underlying Linjiang Fm.
Upper contact
Schematic stratigraphic section shows next higher regional unit is a Baifangzi Fm of Qingbaikouan (Tonian) (not in Lexicon). Regionally, next higher unit is the mid-Lower Tonian age Miaoshan Fm (SE Jilin)
Regional extent
It concentrically spread around Dalizi to Qidaogou gully, the south branch of Sandaogou gully. But it also sporadically crops out in Luannitang, Yaoling and other places.
GeoJSON
Fossils
Age
Depositional setting
Additional Information