Hongguleleng Fm
Type Locality and Naming
Northwest Junggar. The type section is located at 1.5 km west of Bulongour Reservoir, between Hoxtolgay and Utubulak in Hoboksar Mongol Autonomous County, the Xinjiang Uygur Autonomous Region. It was named by the Chinese Academy of Geological Sciences and the Xinjiang Team of Regional Geological Survey in 1973 and formally quoted by Hou Hongfei et al. in 1979.
Lithology and Thickness
Limestone and Tuffaceous claystone. This carbonate formation, totaling 244 m in thickness, is located at the western (overturned) limb of the syncline. It is divided into three members:
Lower member, about 108 m thick, is marked by gray thin-bedded shelly limestone, calcarenites and crinoidal limestone with shale intercalations. Next above are gray, thin-bedded intercalations of calcarenites, shale and crinoidal limestone. Upwards in this lower member, there are shale and limestone gradationally intercalated with green and purple tuffaceous mudstone.
Middle member, 110 m thick, is characterized by interbeds of green and purple tuffaceous silty mudstone with horizontal lamination, intercalated with limestone nodules and micritic sandstone.
Upper member, only 18 m thick, is composed of grayish-yellow thin-bedded calcareous siltstone, intercalated with lenses of coarse-grained crinoidal limestone about 2 m thick at the base.
Relationships and Distribution
Lower contact
The Hongguleleng Fm may be in conformable contact with the underlying tuffaceous sandstone and conglomerate of the Zhulumute Fm.
Upper contact
The top of the formation is in a conformable contact with the overlying calcarenite and siltstone of the Heishantou Fm (lowest Carboniferous), which yields the brachiopod Syringothyris.
Regional extent
This formation, outcropping sporadically southwest of Emuhak Mt. in Aherbulak, is similar in lithology to what can be observed in bulongour area. Southwards, to north of Hoxtolgay Township and Buke River, the lithology is nearly the same, although the coarse-grained clastics and thickness increase and volcaniclastics appear in the lower part.
GeoJSON
Fossils
Lower part of this lower member yields brachiopods Cyrtospirifer sphaeroide. The middle part of the lower member yields abundant brachiopods: Paleospirifer sinicus, Centrorhynchus turanica, Mesoplica semplicior, Aposiella quadratus, Cleiothyridina sp., corals: Nalivkinella profunda, Nexon; Amplexocarinia tenuiseptata, Tabulophyllum postnormale; crinoids Eutaxocrinus.
Middle member yields trilobite Phacops accipitrinus mobilis.
Upper member yields very abundant blastoids and sparse crinoids.
Age
Depositional setting
Additional Information