Phra Wihan Formation

Phra Wihan Formation Stratigraphic range: Early Cretaceous
Type	Geological formation
Unit of	Korat Group
Underlies	Sao Khua Formation
Overlies	Phu Kradung Formation
Thickness	~150m
Lithology
Primary	Sandstone
Other	Shale
Location
Region	Northeast Thailand (Khorat Basin)
Country	Thailand
Type section
Named for	Named after Khao Phra Wihan, an 11th-century Khmer Temple in the area, where this Formation is well exposed. (See, Khao Phra Wihan National Park)

The Early Cretaceous Phra Wihan Formation is the second lowest member of the Mesozoic Korat Group which outcrops in Northeast Thailand.

Comprises fine- to coarse-grained sheet and channelled sandstone beds and rarer variegated siltstone and mudstone. Intermittent conglomerate beds.

Deposited in a fluvial environment dominated by high-energy, shallow braided rivers with subordinate lower energy meandering river systems and associated flood plains.

The Phra Wihan Formation is considered to be Berriasian-Barremian in age based on recent palynology evidence.

Sauropod (fossil) tracks have been recorded from this formation.

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