Gudian Fm
Period:
Cretaceous
Age Interval:
Early Cretaceous, (32b)
Province:
Sichuan
Type Locality and Naming
Sichuan Basin - central. Gudianchang in Zongjiang County, Sichuan Province; named by Sichuan Air Geological Survey Team, 1980, Explanatory Text for 1:200 000 Scale Geological Map: Langzhong, Deyang, Santai, Jianyang and Zigong Sheet.
Lithology and Thickness
Mainly brick-red siltstone and mudstone, interbedded with medium- and fine-grained sandstone
Lithology Pattern:
Siltstone
Relationships and Distribution
Lower contact
The Qiqusi Formation is the next older unit regionally.
Upper contact
In south Sichuan Basin, a major erosion or non-deposition through the rest of the Cretaceous. But, for regional generalized column (including south Sichuan Basin), the next younger (or overlapping) unit is the Jiading Gr (Wotoushan Fm).
Regional extent
GeoJSON
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Fossils
Age
The next younger, but largely coeval, unit of the Wutoushan Fm (which is in south Sichuan Basin) is implied as spanning the same late Aptian through Albian as the Gudian Fm (in central Sichuan Basin); but for graphic purposes to insert the Wotoushan Fm (lowest unit in south Sichuan Basin), the span is split in two.
Age Span:
Beginning stage:
Aptian
Fraction up in beginning stage:
0.75
Beginning date (Ma):
115.25
Ending stage:
Albian
Fraction up in the ending stage:
0.5
Ending date (Ma):
106.85
Depositional setting
Depositional pattern:
Additional Information
Compiler: