Halahatang Fm
Type Locality and Naming
Dong Yanru named it in 1990. The named section is located in the Yuexian 1 well at 83°04′E and 41°51′N in the northeastern part of the Tarim Basin, Xinjiang; the reference section (upper section of the group) is located in the Sha 13 well about 40 km southwest of Xinhe County, Xinjiang. Uppermost formation in Manjiar Gr.
Synonym: In 1984, Huang Youyuan named the Triassic of the Yueshan 1 well as the Manjar Group and subdivided it into the lower, middle and upper groups. In 1990, Dong Yanru named the upper group as the Halahatang Group. In 1990, Dong Yanru named the upper group as the Halahatang Group, and added a section of the stratigraphy in the Shasen 13 well as the upper section of the group in the named section
Lithology and Thickness
It is divided into two sections. The lower part of the lower section is light gray siltstone and fine sandstone, gray-black and gray-yellow fine conglomerate sandwiched between thin layers of dark gray mudstone, 27.5 m thick; the middle part is gray-brown and dark gray mudstone, charcoal mudstone sandwiched between light gray siltstone and thin coal seam, 86 m thick; the upper part is yellow-green and dark gray mudstone, siltstone sandwiched between siltstone, 51.5 m thick. The upper section is light gray-green, gray-white fine-grained feldspathic quartz sandstone, conglomerate-bearing sandstone interspersed with gray-green mudstone and carbonaceous mudstone interspersed with coal line, 91 m thick.
Relationships and Distribution
Lower contact
At the bottom, the gray-black and gray-yellow fine conglomerate is in integrated contact with the underlying Akekule Fm
Upper contact
At the top, it is in pseudo-integrated contact with the overlying Lower Cretaceous.
Regional extent
Widespread in the Tarim Basin
GeoJSON
Fossils
Containing microspores: lower Acritarchs-Alisporites-Colpectopollis assemblage and upper Cyclograni- sporites-Osmundacidites-Aratrisporites assemblage; macrospores: Hughesisporites-Verrutriletes-Trileites (Cala- mospora) assemblage.
Age
Depositional setting
This group is a shallow lacustrine and fluvial deposit, distributed in the Awati area east to Caohu and Abbas, and north to Xinhe Rotai Fault Ridge.
Additional Information