Phra Wihan Formation

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

Phra Wihan Formation
Stratigraphic range: Berriasian-Valanginian ~145–133.6 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Type	Geological formation
Unit of	Khorat Group
Underlies	Sao Khua Formation
Overlies	Phu Kradung Formation
Thickness	150 m (490 ft)
Lithology
Primary	Sandstone
Other	Siltstone, mudstone, conglomerate
Location
Coordinates	16.1°N 103.9°E / 16.1; 103.9
Approximate paleocoordinates	14.3°N 111.4°E / 14.3; 111.4
Region	Northeast Thailand (Khorat Basin)
Country	Thailand
Extent	Khorat Plateau
Type section
Named for	Phra Wihan, an 11th-century Khmer Temple
Named by	Ward & Bunnag
Year defined	1964
Phra Wihan Formation (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-Valanginian in age based on palynological analysis.^[1][2][3]

Sauropod (fossil) tracks have been recorded from this formation.^[4]

See also

• List of dinosaur-bearing rock formations
  • List of stratigraphic units with sauropodomorph tracks
    • Sauropod tracks