Sanjian Gr
Period:
Ordovician
Age Interval:
Later Ordovician, (54)
Province:
Guangdong
Type Locality and Naming
The Sanjian Gr was named by Guangdong Team of Regional Geological Survey in 1964, and was published by Central-South Compiling Group for Regional Stratigraphic Scale (1974). The type section is on Sanjian Hill in Liantan, Yunnan, Guangdong.
Synonym: (三尖群）
Lithology and Thickness
The Group is dominated by sandy shale and quartz sandstone. It recorded a thickness of 500-1730 m.
Lithology Pattern:
Sandy claystone
Relationships and Distribution
Lower contact
It rests conformably on the Suoweiling Gr
Upper contact
It is conformably overlain by the sandstone of the Lower Silurian (Liantan Fm), which is indicated to begin in mid-Hirnantian.
Regional extent
GeoJSON
null
Fossils
Age
Late Ordovician.
Age Span:
Beginning stage:
Darriwilian
Fraction up in beginning stage:
0.95
Beginning date (Ma):
458.74
Ending stage:
Hirnantian
Fraction up in the ending stage:
0.5
Ending date (Ma):
444.14
Depositional setting
Depositional pattern:
Additional Information
Compiler:
Jianpo Wang and Xiaofeng Wang