Mesozoic • Cretaceous In GSP lexicon

Pab Sandstone

Late Cretaceous (Maastrichtian)

Cited in 14 sources Last reviewed Aug 10, 2026

Unit summary

Rank: Not recorded
Status: Published
Age: Mesozoic · Cretaceous · Late Cretaceous (Maastrichtian)Late Cretaceous (Maastrichtian)
Named by: Vredenburg (1909)
Type locality: West of Wirahab Nai, Pab Range25.5200°N, 67.0053°E
Thickness: 240–1,000 m (490 m at the Pab Range type section)
Lithology: White, cream or brown, thick-bedded to massive, cross-bedded, medium- to coarse-grained quartzose sandstone with subordinate argillaceous limestone and shale.
Synonyms: Not recorded

A thick, clean Maastrichtian sandstone of the Pab Range — one of the main oil-and-gas reservoir rocks of the Indus Basin.

Major sandstone unit in Sulaiman and Kirthar basins. Represents coastal to shallow marine conditions. Good petroleum reservoir.

Fossils

Bivalves Gastropods Trace fossils

Contacts

In the Sulaiman Fold Belt column

LimestoneShale / mudSandstoneFossils 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 Kirthar Range Bela-Khuzdar

Basin: Not recorded
Region: Not recorded
Depositional environment: marginal marine, deltaic
Coordinates: 25.5200°N, 67.0053°E

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See it in the field

Geoheritage site where this unit is exposed at outcrop.

Pab Range

Kirthar Range

Correlation

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

Economic significance

Reservoir

A major quartzose-sandstone hydrocarbon reservoir in the Lower Indus Basin.

Remarks

A widespread Maastrichtian quartzose sandstone resting on the Fort Munro Formation (locally on the Parh Limestone); its clean, cross-bedded sands form a major regional petroleum reservoir and mark the terminal Cretaceous clastic influx into the Indus shelf.

Research notes (9)

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

Thickness (1)

Type-section thickness (Shah, 2009): 490 m at type section; >600 m S/W of Khuzdar; 450 m Fort Munro anticline; ~240 m W of Mughal Kot; pinches out in Marri-Bugti hills. Type locality: 'Somalji trail' west of Wirahab Nai, across the Pab Range, Kirthar Province. Recorded from the GSP lexicon (Memoir 22); the existing thickness field is retained.

Shah, S.M.I. (2009)

Stratigraphic contacts (1)

Umar et al. (2024): the Pab Formation conformably overlies the Fort Munro, Mughal Kot and/or Bibai formations (SFTB, KFTB and IESZ respectively) and is conformably overlain by the Moro Formation in the Spera Ragha–Chinjun area. It is 490 m thick at its type locality (SKFTB) but as thin as 2–7 m in the Quetta Syntaxis and is entirely absent between Khuzdar and Quetta.

Umar, M., Kassi, A.M., Jamil, M., Kasi, A.K. & Khan, A.S. (2024)

Fossils & biostratigraphy (1)

Umar et al. (2024, after Vredenburg 1908; Malkani 2006): the Pab Formation carries the foraminifer Lepidorbitoides and a Maastrichtian vertebrate fauna including mesoeucrocodylian baurusuchids, abelisaurian theropods and titanosaurian sauropods; deposited in fluvio-deltaic (proximal) to submarine-slope/turbidite (distal) settings.

Umar, M., Kassi, A.M., Jamil, M., Kasi, A.K. & Khan, A.S. (2024)

Depositional environment (2)

Thebo et al. (2023): Chemical Index of Alteration (CIA 61-84) and Plagioclase Index of Alteration (PIA 60-89) for the Laki-Range Pab Sandstone indicate moderate-to-intense chemical weathering in the source area under a warm, humid palaeoclimate. Records a palaeoweathering/palaeoclimate constraint (the curated marginal-marine/deltaic depositional environment is retained).

Thebo, G.M., Solangi, S.H., Agheem, M.H., Solangi, M.A., Markhand, A.H. & Memon, K.A. (2023)
Hemphill & Kidwai (1973, USGS PP 716-B): the Late Cretaceous (Maastrichtian) Pab Sandstone in the Sulaiman Range is quartzitic, commonly crossbedded sandstone (conglomeratic near the base) with burrows and plant roots and oil seeps ~125 ft below the top; crossbedding indicates westerly sediment transport; ~776 ft west of Mughal Kot, thickening southward. Keizer suggested its upper part may range up into the late Paleocene.

Hemphill, W.R. & Kidwai, A.H. (1973)

Economic significance (1)

Asim et al. (2014): in the Drigri and Kotrum anticlines (Central Indus Basin) the Late Cretaceous Pab Sandstone forms a RESERVOIR sealed by the overlying Paleocene Ranikot shales — a structural (gentle-anticline) trap of the Safed Koh Trend.

Asim, S., Qureshi, S.N., Asif, S.K., Abbasi, S.A., Solangi, S. & Mirza, M.Q. (2014)

Geological significance (3)

Malkani (2016) reports evidence of Deccan volcanism within the Maastrichtian Pab Formation of the Sulaiman/Kirthar (middle-lower Indus) basins, consistent with the Deccan volcanic dust recorded in the overlying earliest-Paleocene Sangiali and Rakhi Gaj / Khadro formations near the K/Pg boundary.

Malkani, M.S. (2016)
Malkani et al. (2017, 2022): the Pab Sandstone (Middle–Late Maastrichtian; ~500–600 m; Fort Munro Group) is subdivided into a lower Dhaola Member (white quartzose sandstone), a middle Kali Member (shale + black-weathering sandstone) and a Sor Member (dominantly maroon shale and sandstone; type Sor Muzghai; extending Qila Saifullah → Shirani → Waziristan). The Sor Member is reported to carry Maastrichtian archosaur trackways (ichnotaxa Pashtosauroperus zhobi 'Ornithopaonia' and the pterosaur track Anmolpakhiperus alleni 'Pteropaonia'), the Dhaola Member the fish Kahamachli harrandlundi, and the unit conifer wood Baradarakht goeswangai. In North/South Waziristan the Pab equivalent is named the Khajuri Post Formation (thick-bedded cherty faintly cross-bedded sandstone). Attributed Malkani-corpus ichno/taxa.

Malkani, M.S., Khosa, M.H., Alyani, M.I., Somro, N., Zafar, T., Arif, J. & Aleem, M.Z. (2017)
Thebo et al. (2023), petrography and major-element geochemistry of the Pab Sandstone at the Laki Range (Southern Indus Basin): the sandstone (with subordinate conglomeratic-sandstone and mudstone beds) is dominated by monocrystalline, non-undulatory quartz with minor feldspar and lithics, cemented mainly by iron oxide with some calcareous cement. QFL and QmFLt modal plots indicate a craton-interior / continental-block provenance, with detritus derived from a granite-dominated cratonic landmass (the Indian Shield) - the exposed Nagar Parkar Igneous Complex (SE Pakistan) and the Malani Igneous Suite (India) - plus a minor mafic input. Adds an explicit provenance signal for the Pab clastics.

Thebo, G.M., Solangi, S.H., Agheem, M.H., Solangi, M.A., Markhand, A.H. & Memon, K.A. (2023)

Sources (14)

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.
OpenStreetMap contributors and GEOnet Names Server (public geographic gazetteers), used to geolocate named GSP type localities to approximate decimal coordinates.
Indian Plate Lexicon (indplex.geolex.org), Geological Society of India and international compilation.
Malkani, M.S. (2016). Revised stratigraphy of Indus Basin (Pakistan): Sea level changes. In: Cretaceous Ecosystems and Their Responses to Paleoenvironmental Changes in Asia and the Western Pacific — Fourth International Symposium of IGCP Project 608, Novosibirsk 2016, Abstract Volume, pp. 97-99.
Shah, S.M.I. (2009). Stratigraphy of Pakistan. Geological Survey of Pakistan, Memoir Vol. 22.
Malkani, M.S., Khosa, M.H., Alyani, M.I., Somro, N., Zafar, T., Arif, J. & Aleem, M.Z. (2017). Revised Stratigraphic Setup and Mineral Deposits of Kirthar Basin (Lower Indus Basin), Pakistan. Lasbela University Journal of Science and Technology, VI, 54-84.
Malkani, M.S., Ilyas, M., Yasin, R., Abbas, A., Samiullah, K., Raza, T., Hassan, S.S.E., Fazal, R.M., Noor, A. & Malik, A. (2022). Geology of Northern Sulaiman Foldbelt, Shirani and Waziristan Regions (South Punjab, Balochistan and Khyber Pakhtunkhwa): New Tomistominae (Miocene False Gharial) from Sakhi Sarwar Area of Dera Ghazi Khan (South Punjab), Pakistan. Open Journal of Geology, 12(6), 521-564.
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.
Asim, S., Qureshi, S.N., Asif, S.K., Abbasi, S.A., Solangi, S. & Mirza, M.Q. (2014). Structural and Stratigraphical Correlation of Seismic Profiles between Drigri Anticline and Bahawalpur High in Central Indus Basin of Pakistan. International Journal of Geosciences, 5(11), 1231-1240.
Malkani, M.S., Mahmood, Z., Somro, N. & Shaikh, S.I. (2017). Revised Stratigraphy and Mineral Resources of Kirthar Basin, Pakistan. Geological Survey of Pakistan, Information Release No. 1010.
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.
Thebo, G.M., Solangi, S.H., Agheem, M.H., Solangi, M.A., Markhand, A.H. & Memon, K.A. (2023). Petrography and Geochemistry of late Cretaceous Pab Sandstone, Laki Range, Southern Indus Basin, Pakistan: implications for Provenance and Paleoclimate. Journal of Himalayan Earth Sciences, 56(1), 65-78.
Hemphill, W.R. & Kidwai, A.H. (1973). Stratigraphy of the Bannu and Dera Ismail Khan Areas, Pakistan. U.S. Geological Survey Professional Paper 716-B (Geological Investigations in Pakistan), 36 p.

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.

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Cite this unit

APA

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

BibTeX

@misc{stratigraphypk_pabsandstone,
  author    = {Qudsi, Lareb},
  title     = {{Pab Sandstone} --- 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/pab-sandstone (accessed October 29, 2026).

To cite the unit's original definition instead, see: Vredenburg (1909).

Below · older

Fort Munro Formation

Cretaceous

Above · younger

Moro Formation