Precambrian • Precambrian formation GSP memoir

Sobrah Formation

Precambrian

Northern Indus Suture

Precambrian in the time scale →

Cited in 3 sources Last reviewed Jul 17, 2026

Unit summary

Rank: formation
Status: Under review
Age: Precambrian · PrecambrianPrecambrian
Named by: Not recorded
Type locality: Near Tarbela Dam, Khyber Pakhtunkhwa
Thickness: Not recorded
Lithology: Thin limestone unit overlying the Manki Formation near Tarbela Dam.
Synonyms: Not recorded

A poorly characterised formation of the Nowshera/Peshawar Paleozoic area.

Fossils

Not recorded

Contacts

In the Khyber–Nowshera Belt column

LimestoneMetamorphicContact not recorded

Band colour = period; texture = dominant rock type. Lines between bands mark the contact type; dotted = no contact recorded in the sources (not a claim of conformity). 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

Khyber–Nowshera Belt

Basin: Northern Indus Suture
Region: Not recorded
Depositional environment: Not recorded
Coordinates: Not recorded

Correlation

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

Economic significance

Not recorded

Remarks

A formation of the Nowshera/Peshawar Paleozoic area; its lithology and age are not well established in the baseline.

Research notes (1)

Field-by-field findings drawn from the cited literature. Every statement is traced to a registered source — follow a citation for the full reference.

Age & correlation (1)

Characterised from Hylland, Riaz & Ahmad (1988): a thin limestone overlying the Manki Formation near Tarbela Dam, considered correlative with the Precambrian Shekhai Formation on lithologic grounds (K.R. Pogue, pers. comm.). This supersedes the baseline 'age not well established' note; kept under review because the correlation rests on a personal communication.

Hylland, M.D., Riaz, M. & Ahmad, S. (1988)

Sources (2)

Malkani, M.S. & Mahmood, Z. (2017). Stratigraphy of Pakistan. Geological Survey of Pakistan, Memoir Vol. 24.
Hylland, M.D., Riaz, M. & Ahmad, S. (1988). Geology of the Southern Gandghar Range, Pakistan. Geological Bulletin, University of Peshawar, Vol. 21, pp. 1-14.

Reviewer confidence: medium

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: Appears in a single-author Geological Survey of Pakistan memoir (Malkani & Mahmood 2017), not cross-confirmed against the Shah lexicon. The Stratigraphic Committee of Pakistan is largely inactive, so documented provenance — not formal ratification — is the available signal.

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Cite this unit

APA

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

BibTeX

@misc{stratigraphypk_sobrahformation,
  author    = {Qudsi, Lareb},
  title     = {{Sobrah 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/sobrah-formation (accessed October 29, 2026).

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Manki Formation