Gupa Fm
Type Locality and Naming
The type section is located at Yingtang Village of Dale in Xiangzhou County, Guangxi. It was named by Hou Hongfei and Xian Siyuan in 1975.
Synonym (translation option): Guba Fm
[Figure Locations of Dale Fm (A, B) and Gupa Fm and Guche Fm (C) in Dale area]
Lithology and Thickness
Claystone. It is dominated by thin-bedded earth-yellow mudstone, composed mainly of hydromica clay minerals with a few muscovite and quartz clastics, and is intercalated with few thin beds or lenses of clayey limestone and bioclastic limestone near the upper part. It is 85.7 m thick.
[Figure - Outcrops of Gupa Formation in the type locality at Dale showing the mudstone (left) with limestone interbeds (right), length of hammer 28 cm.]
Relationships and Distribution
Lower contact
A basal bed of clayey limestone separates it at a conformable contact from the underlying Dale Fm.
[Figure Photography showing the boundary between Dale and Gupa Formations (white line), the contact is taken at the change from grayish limestone to yellow mudstone (after Ma et al., 2007).]
Upper contact
It is conformable contact with the overlying Guche Fm.
Regional extent
This formation is mainly distributed in the west side of Dayaoshan Mt. From north to south the clayey content gradually decreases while the calcareous one increases.
GeoJSON
Fossils
It contains abundant brachiopods including a Xenospirifer fongi assemblage in the lower part and an upper Eospiriferina lachrymosa assemblage, and corals Cylindrophyllum agglomeratum, Phacellophyllum daleense. Utaratuia sinensi; as well as dacyoconarid Nowakia sulcata.
Age
Depositional setting
It is interpreted as a subtidal sedimentary environment.
Additional Information