Pong Nam Ron Fm
Period:
Triassic
Age Interval:
Late Triassic (Carnian) (12)
Province:
SE Thailand: Klaeng Zone
Type Locality and Naming
Type area: Eastern parts of Chanthaburi, Trat and Sa Kaeo provinces. Middle formation in the Chanthaburi Gr.
Synonym: หินบะซอลต์โป่งน้ำร้อน
[Figure 1 : Generalized distribution of different Triassic sedimentary environments and some of the more important lithostratigraphic units, and their relations to the terranes. (The geology of Thailand, 2011) page 146]
Lithology and Thickness
Greywacke, greenish grey, dark grey, fine- to medium grained, poorly to moderately sorted, thin to massive, graded bedded, small scale cross bedded; interbedded shale and locally thin-bedded limestone. Over 200 m.
Lithology Pattern:
Clayey sandstone
Relationships and Distribution
Lower contact
Noen Po Fm (conformably)
Upper contact
Noen Phu Yai Yua Fm (conformably)
Regional extent
Chanthaburi area (where near the Gulf of Thailand), SE Thailand (Sukhothai Zone extension).
[Figure 2 : Generalized distribution of marine Triassic sedimentary rocks in Thailand (in purple) (modified after Mantajit 1999). (The geology of Thailand, 2011) page 138]
GeoJSON
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Fossils
Age
Implied by Fig. 6.2 in Chonglakmani (2011) to span approximately the later part of the early Carnian.
Age Span:
Beginning stage:
Carnian
Fraction up in beginning stage:
0.25
Beginning date (Ma):
234.86
Ending stage:
Carnian
Fraction up in the ending stage:
0.5
Ending date (Ma):
232.73
Depositional setting
Inner submarine fan deposits (Chaodumrong, 1992).
Depositional pattern:
Additional Information
Remarks: Nomenclature-basanite
Compiler:
Wen Du - modified from- Chonglakmani, C.P., 2011, Chapter 6 Triassic in Ridd, M.F., Barber, A.J., and Grow, M.J., editors, The Geology of Thailand, Geol. Soc. of London.；Lexicon of Stratigraphic Names of Thailand of 2013.