Quaternary • Quaternary In GSP lexicon

Soan Formation

Pliocene to Pleistocene

Cited in 9 sources Last reviewed Jul 30, 2026

Unit summary

Rank: Not recorded
Status: Published
Age: Quaternary · Quaternary · Pliocene-PleistocenePliocene to Pleistocene
Named by: Cheema et al. (1977)
Type locality: Not recorded
Thickness: 120-450 m in Trans Indus-Potwar Province (TrI-PP) m
Lithology: Boulder conglomerate, sandstone, silt
Synonyms: Suan

A capping layer of coarse Plio-Pleistocene boulder gravel — the youngest Siwalik deposit, shed from the rising Himalaya.

Coarse alluvial fan deposits from rapidly rising Himalaya. Contains famous Soan Culture Paleolithic tools. Upper unit of the Soan Group.

Fossils

Not recorded

Contacts

In the Potwar Basin column

ConglomerateSandstoneFossils recordedConformable

Band colour = period; texture = dominant rock type. Lines between bands mark the contact type. True scale makes height ∝ recorded thickness; hatched = thickness not recorded. Ages approximate, for ordering.

This unit (highlighted) within its province column; faded ends continue above and below. Line style marks the contact type.

Distribution & setting

Potwar Basin Kohat Basin

Basin: Not recorded
Region: Not recorded
Depositional environment: fluvial, continental
Coordinates: Not recorded

Correlation

Not recorded. Compare this unit against other basins on the correlation panel →

Economic significance

Not recorded

Remarks

The youngest, boulder-conglomerate-dominated unit of the Siwalik molasse (the Urak Boulder Conglomerate of the Sibi region), capping the foreland succession; its coarse Plio-Pleistocene gravels record the final, high-energy unroofing of the rising Himalaya.

Sources (8)

Malkani, M.S. & Mahmood, Z. (2017). Stratigraphy of Pakistan. Geological Survey of Pakistan, Memoir Vol. 24.
Kazmi, A.H. & Jan, M.Q. (1997). Geology and Tectonics of Pakistan. Graphic Publishers, Karachi.
Shah, S.M.I. (1977). Stratigraphy of Pakistan. Geological Survey of Pakistan, Memoir Vol. 12.
Indian Plate Lexicon (indplex.geolex.org), Geological Society of India and international compilation.
Rendell, H.M., Hailwood, E.A. & Dennell, R.W. (1987). Magnetic polarity stratigraphy of Upper Siwalik Sub-Group, Soan Valley, Pakistan: implications for early human occupance of Asia. Earth and Planetary Science Letters, 85, 488-496.
Iqbal, O., Baig, M.S., Pervez, S. & Siddiqi, M.I. (2018). Structure and Stratigraphy of Rumbli and Panjar Areas of Kashmir and Pakistan with the Aid of GIS. Journal of the Geological Society of India, 91, 57-66.
Opdyke, N.D., Lindsay, E., Johnson, G.D., Johnson, N., Tahirkheli, R.A.K. & Mirza, M.A. (1979). Magnetic polarity stratigraphy and vertebrate paleontology of the Upper Siwalik subgroup of northern Pakistan. Palaeogeography, Palaeoclimatology, Palaeoecology, 27, 1-34.
Gill, W.D. (1951). The stratigraphy of the Siwalik Series in the Northern Potwar, Punjab, Pakistan. Quarterly Journal of the Geological Society of London, 107, 375-394.

Reviewer confidence: high

Every fact on this page is source-cited. This entry is part of the peer-archived Pakistan Stratigraphy Dataset (doi.org/10.5281/zenodo.21363991, CC‑BY‑4.0).

Lexicon status: Name attested in the Shah (1977/2009) Geological Survey of Pakistan compilation — the national stratigraphic lexicon. This records where the name is documented; it is not an endorsement of the unit’s definition, age or figures.

Cite this unit

APA

Qudsi, L. (2026). Soan Formation. In Pakistan Stratigraphy Dataset [Data set]. Zenodo. https://doi.org/10.5281/zenodo.21363991

BibTeX

@misc{stratigraphypk_soanformation,
  author    = {Qudsi, Lareb},
  title     = {{Soan Formation} --- Pakistan Stratigraphy Dataset},
  year      = {2026},
  publisher = {Zenodo},
  doi       = {10.5281/zenodo.21363991},
  url       = {https://doi.org/10.5281/zenodo.21363991}
}

Archived dataset: doi.org/10.5281/zenodo.21363991 (CC‑BY‑4.0) · Direct link to this entry: https://stratigraphy.pk/formation/soan-formation (accessed September 5, 2026).

To cite the unit's original definition instead, see: Cheema et al. (1977).

Referenced in other successions

Underlain by Lei Conglomerate