Nam Phong Formation

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Nam Phong Formation
Stratigraphic range: Late Triassic-Late Jurassic
~220–160  Ma
Type Geological formation
Underlies Phu Kradung Formation
OverliesIndosinian II Unconformity
Thickness1,465 m (4,806 ft)
Lithology
Primary Sandstone
Other Conglomerate, siltstone, mudstone
Location
Coordinates 16°18′N102°00′E / 16.3°N 102.0°E / 16.3; 102.0
Approximate paleocoordinates 20°54′S93°00′E / 20.9°S 93.0°E / -20.9; 93.0
Region Isan
Country Thailand
Extent Khorat Plateau
Type section
Named byWard & Bunnag
Year defined1964
Thailand location relief map.svg
Blue pog.svg
Nam Phong Formation (Thailand)

The Nam Phong Formation, which correlates to the Indosinian III Unconformity, is a geological formation in Thailand. It underlies the Khorat Group. It consists of resistant, red-brown micaceous sandstones, conglomerates, siltstones and mudstones of mainly fluvial origin. The sandstones are medium to very fine-grained and are usually calcareous. The conglomerates contain pebbles of quartz, brown and grey chert, and reddish brown siltstone. Cross bedding and plane-bed stratification are common in the sandstones and conglomerates. The sandstones and conglomerates make up approximately 30% of the formation. This sedimentary rock formation is found in Khon Kaen Province, Thailand. It is of Norian to Rhaetian age (Upper Triassic) to (Lower Jurassic) age, and is notable for its fossils of early dinosaurs. [1]

Contents

Vertebrate paleofauna

Indeterminate prosauropod remains are present in Khon Kaen Province. [1]

Color key
Taxon Reclassified taxonTaxon falsely reported as presentDubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Dinosaurs

Dinosaurs of the Nam Phong Formation
GenusSpeciesLocationStratigraphic positionMaterialNotesImages
Isanosaurus [1] I. attavipachi [1] Khon Kaen Province [1] "Associated fragmentary vertebrae, ribs, chevrons, scapula, sternal, femur." [2] A primitive sauropod
Sauropoda Indet. [3] Indeterminate

Correlations

The formation has been correlated with the Lower Elliot Formation (Karoo Basin) and Forest Sandstone of Africa, the Caturrita Formation of the Paraná Basin in Brazil, the Laguna Colorada and Los Colorados Formations (Ischigualasto-Villa Unión Basin) of Argentina, the Chinle Formation of North America, the Trössingen Formation of the Keuper Group of Germany, and the Lower Dharmaram Formation of India. [4]

See also

References

  1. 1 2 3 4 5 Weishampel et al., 2004, pp.525–527
  2. "Table 13.1," in Weishampel et al., 2004, p.261
  3. Hanta, R.; Sekiya, T.; Shibata, M.; Naksri, W.; Tucker, R. T. (2023). "Hatchling and Early Juvenile of Early Sauropod from the Early Middle Jurassic Nam Phong Formation, Chaiyaphum Province, Northeastern Thailand". Paleontological Research. 28 (3): 222–239. Bibcode:2023PalRe..28.0002H. doi:10.2517/PR230002. S2CID   261448098.
  4. Novas et al., 2011, p.343

Bibliography