Mesozoic • Cretaceous formation In GSP lexicon

Fort Munro Formation

Cretaceous

Sulaiman Basin

Part of Fort Munro Group

Cretaceous in the time scale →

Cited in 7 sources Last reviewed Aug 2, 2026

Unit summary

Rank: formation
Status: Published
Age: Mesozoic · Cretaceous · Late Cretaceous (Maastrichtian)Cretaceous
Named by: Williams (1959)
Type locality: Fort Munro, in the hills along the Fort Munro–Dera Ghazi Khan road, eastern Sulaiman Range (Rakhi Nala designated as reference section)29.9539°N, 70.1772°E
Thickness: 100m
Lithology: Dark-grey, hard, thick-bedded limestone with marly and shaly interbeds in the Sulaiman area; grey to cream, thin-bedded above and thick-bedded to massive, reefoid below in the Kirthar area.
Synonyms: Not recorded

A Maastrichtian reef-and-shelf limestone forming the top of the Cretaceous limestones, just below the Pab Sandstone.

Introduced by Williams (1959) as the upper limestone member of the Mughal Kot Formation (type section on the western flank of the Fort Munro anticline) and raised to formation rank by Fatmi (1977), the Fort Munro Formation is grey-to-brown, thin-to-thick-bedded limestone with minor greenish-grey shale, about 100–150 m thick. Its lower contact with the Mughal Kot Formation and upper contact with the Pab Formation are transitional and conformable. Larger foraminifera (Omphalocyclus, Orbitoides, Siderolites) indicate a Late Campanian–Maastrichtian age (Williams, 1959; HSC, 1961).

Fossils

Omphaocyclus sp Orbitoides sp.

Contacts

In the Sulaiman Fold Belt column

SandstoneShale / mudLimestoneFossils recordedContact 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

Sulaiman Fold Belt

Basin: Sulaiman Basin
Region: Not recorded
Depositional environment: shallow marine, reef
Coordinates: 29.9539°N, 70.1772°E

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Correlation

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

Economic significance

Other

Building-limestone source.

Remarks

A Maastrichtian shelf-and-reef limestone capping the Cretaceous carbonates of the Sulaiman–Kirthar belts; conformably overlying the Mughal Kot Formation and overlain by the Pab Sandstone.

Research notes (4)

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

Name & nomenclature (1)

Attested in Shah (2009), Geological Survey of Pakistan Memoir 22 - the Stratigraphic Committee of Pakistan's compiled lexicon (listed in the memoir's contents). Adds the definitional GSP/SCP lexicon citation.

Shah, S.M.I. (2009)

Age & correlation (1)

Zaman et al. (2024) and Umar et al. (2024): the Fort Munro Formation is Campanian–Maastrichtian, refining the curated 'Cretaceous' age. It was first mapped as the Hippuritic Limestone (Blanford 1878) and Hemipneustes Limestone (Vredenburg 1909), treated as a member of the Mughal Kot Formation (Williams 1959) and raised to formation rank by Fatmi (1977).

Zaman, B.U., Mohibullah, M., Manan, R.A., Kassi, A.M. & Rizwan, M. (2024)

Stratigraphic contacts (1)

Zaman et al. (2024): the Fort Munro Formation conformably overlies the Mughal Kot Formation and is conformably overlain by the Pab Formation in most of the SFTB; where the Mughal Kot facies is absent (e.g. Quetta) it rests unconformably on the Parh Group, and around Quetta it is disconformably overlain (lateritic bed) by the Paleocene–Eocene Dungan Formation.

Zaman, B.U., Mohibullah, M., Manan, R.A., Kassi, A.M. & Rizwan, M. (2024)

Fossils & biostratigraphy (1)

Zaman et al. (2024): the fuller larger-benthic-foraminifera assemblage is Orbitoides media, O. tissoti minima, Omphalocyclus macropora, Actinosipon punjabensis and species of Siderolites, with abundant Hippurites bivalves — indicating an inner-to-middle ramp (semi-restricted, storm-induced skeletal shoals, lagoon and open-marine sub-environments).

Zaman, B.U., Mohibullah, M., Manan, R.A., Kassi, A.M. & Rizwan, M. (2024)

Sources (7)

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.
Malkani, M.S. (2010). Updated Stratigraphy and Mineral Potential of Sulaiman Basin, Pakistan. Sindh University Research Journal (Science Series), 42(2), 39-66.
Shah, S.M.I. (2009). Stratigraphy of Pakistan. Geological Survey of Pakistan, Memoir Vol. 22.
Kazmi, A.H. & Abbasi, I.A. (2008). Stratigraphy and Historical Geology of Pakistan. Department & National Centre of Excellence in Geology, University of Peshawar, Peshawar. 524 pp. ISBN 978-969-9119.
Zaman, B.U., Mohibullah, M., Manan, R.A., Kassi, A.M. & Rizwan, M. (2024). Detailed sedimentological investigation of the late Cretaceous Fort Munro Formation, western Sulaiman Range, Pakistan. Carbonates and Evaporites, 39, 55.
Umar, M., Kassi, A.M., Jamil, M., Kasi, A.K. & Khan, A.S. (2024). Cretaceous stratigraphic framework and sedimentary architecture, Pakistan: signatures of rift-drift tectonics and submarine volcanism along the western continental margin of the Indian Plate. In: Hart, M.B. et al. (eds) Cretaceous Project 200 Volume 2: Regional Studies. Geological Society, London, Special Publications, 545.

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: 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.

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Cite this unit

APA

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

BibTeX

@misc{stratigraphypk_fortmunroformation,
  author    = {Qudsi, Lareb},
  title     = {{Fort Munro 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/fort-munro-formation (accessed October 29, 2026).

To cite the unit's original definition instead, see: Williams (1959).

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