Zhamure Fm

Synonym: Zamure Fm.

Lithology and Thickness:

The formation consists of bioclastic limestone, phosphorus-bearing bioclastic limestone, silica-bearing argillaceous limestone and siderite limestone interbedded with sandy shale. Its thickness is 99 m.

Lithology-pattern: Limestone

Relationships and Distribution:

Lower contact:

The bottom boundary marked by the appearance of siltstone and fine sandstone is in concordant contact with the underlying Rebussian Fm (Laibuxi Fm).

Upper contact:

The top boundary is marked by the disappearance of phosphorous-bearing bioclastic limestone and siderite limestone is conformably overlain by the siltstone and sandstone in the bottom of the Dashalong Fm.

Regional extent:

GeoJSON:

Fossils:

Ammonoids: (1) Indonesites dieneri zone, (2) Hoplotropites zone, (3) Parahauerites acutus zone. Conodonts: (1) Epigondolella diebeli zone; (2) Neogondolella polygnathiformis zone. And bivalves, brachiopods, foraminifera and mosses, hornstones, ostracods and other fossils.

Age:

Tong et al. (2019, Triassic integrated stratigraphy and timescale in China, Science China: Earth Sciences, v. 62, no. 1) assign it as spanning the Carnian.

Age span:

Beginning stage: Carnian

Fraction up in beginning stage: 0.0

Beginning date (Ma):

Ending stage: Carnian

Fraction up in ending stage: 1.0

Ending date (Ma):

Depositional setting:

Depositional-pattern:

Additional Information

In 1974, Yin Jixiang et al. took the Tulong section in Nyalam County as the stratigraphic type and collectively referred to the Early Triassic Indian to Late Triassic Early Norian strata as the Tulong Gr, which was divided into three subgroups: Upper, Middle and Lower. In 1980, Wang Yigang et al. took the Tulong profile as the stratigraphic type, further divided the Tulong Gr, and named the lower strata of the upper and lower strata of the original Tulong Gr as the Zamure Fm, which was in the Carnian stage. This Lexicon follows this usage (see Kangsha Gr [= Kangshare Fm] for details).