Bagongbulansha Gr
Type Locality and Naming
Karakorum. It was named by the Compiler
Jingeng Sha (coordinator) Group for the region Stratigraphic Chart of the Xinjiang Uygur Autonomous Region in 1981. The naming section is located at Bagongbulansha, north of Tianshendaban, Xinjiang (E 78°12′, N 35°48′).
Synonym: (巴工布兰莎群)
Lithology and Thickness
It is composed of dark-color calcareous sandy shale, light-green and grey sandstone, light-blue limestone and green tuffaceous shale. It is changing facially into sandstone, conglomerate and minor shale; locally there is a 1-3 m thick layer of brick-red basal conglomerate or brown-yellow sandstone and feldspathic gritstone. With a thickness of 1500 m.
Relationships and Distribution
Lower contact
The basal part of the group is in a disconformable contact with the underlying Luoshigou Formation of the middle Devonian, (=limestone with interbeds of sandstone of Mid Devonian according to [Geological Formation Names of China (1866–2000). Springer], but not in draft Devonian Lexicon for this current Compiler
Jingeng Sha (coordinator)). Regionally, the next older unit is the Keleqinghe Gr of Late Triassic.
Upper contact
No top part has been found. Regionally, the schematic strat column indicates the next younger unit is the Longshan Fm
Regional extent
Karakorum. The formation is exposed essentially in the Bagongbulansha area at Tianshendaban, with scattered exposures of it being found to the south of the Kashir Village; and it represents chiefly sandstone, siltstone, mudstone and limestone, with an unknown thickness.
GeoJSON
Fossils
In the Bagongbulansha area there are found abundant plant fossils of the lower Jurassic as represented by Cladophlebis cf. haiburensis, Ptilophyllum cutchense, Phoenicopsis speciosa, P. latior, Pityophyllum nordenskioldi, and Klukia tibetica; Belemnoidea such as Belemnites sp.; Bivalves as represented by Pecten sp. And polyzoa such as Bryozoa sp. to the south of the Kashir Village.
Age
Depositional setting
Additional Information
In the Bagongbulansha area there are found abundant plant fossils of the lower Jurassic as represented by Cladophlebis cf. haiburensis, Ptilophyllum cutchense, Phoenicopsis speciosa, P. latior, Pityophyllum nordenskioldi, and Klukia tibetica; Belemnoidea such as Belemnites sp.; Bivalves as represented by Pecten sp. And polyzoa such as Bryozoa sp. to the south of the Kashir Village.
Age:
Schematic strat column in previous "red Chinese Lexicon" had implied that the Bagongbulansha Gr spanned the Early Jurassic.
Age span:
Beginning stage: Hettangian
Fraction up in beginning stage: 0.0
Beginning date (Ma):
Ending stage: Toarcian
Fraction up in ending stage: 0.5
Ending date (Ma):
Depositional setting:
Depositional-pattern:
Additional Information
Compiler
Jingeng Sha (coordinator)