Hongliugou Fm
Type Locality and Naming
It was named by Wang Jinbing et al in 1966 and published by Lin Baoyu et al in 1984. The type section is located at 10 km south of Pingdingshan Mt., south of Kalamaili Mt. in Qitai County, Xinjiang Uygur Zizhiqu.
Synonym: (红柳沟组)
Reference Section:
The reference section is at southwest of Keankuduk in Mori Kazak Autonomous County.
Lithology and Thickness
It consists of purplish red, alternating with grey green, thin-to-medium-bedded micritic sandstone, micritic siltstone, pelitic siltstone, pelitic siliceous rock and tuff, intercalated with marl or limestone.
Relationships and Distribution
Lower contact
The formation rests conformably on the underlying grayish white Baishanbao Fm at Kalamaili in the west. Its violet, seldom green, base conglomerate disconformably overlies on the Huangcaopo Fm of the Middle and Upper Ordovician in the Kaokeselgai area in east.
Upper contact
The Hongliugou Fm is in conformable transition with the overlying Lower Devonian. Regionally, that lower Devonian might be the Teheirbasite Fm.
Regional extent
It is comparatively steady in lithology, but eastwards the tuffaceous components increase, the grain size becomes coarser, conglomerate appears often, and limestone interbeds increase. The color stability is the important criteria of this formation. It is also steady in thickness from east to west, varying from 340-450 m in general, but northwards the thickness may reach 1097 m. The formation is exposed at Kalamaili Mt. in Qitai County, at Kaldoyi in Fuyun County, at Kaokesailgai, Solbasta'u, Küp and Aozhongke in Barkol and Mori Kazak Autonomous Counties.
GeoJSON
Fossils
The limestone is rich in fossils, mainly corals, such as the Kodonophyllum-Chlamydophyllum assemblage, the Thecia-Mesofavosites-Cladopora assemblage, also trilobite Encrinurus; brachiopods Spirigerina supramarginalis, Grayina etc., and gastropods, bryozoa, bivalves and crinoid columnals as well.
Age
Depositional setting
Additional Information