Paleozoic • Permian In GSP lexicon

Amb Formation

Middle Permian (Wordian)

Cited in 13 sources Last reviewed Aug 20, 2026

Unit summary

Rank: Not recorded
Status: Published
Age: Paleozoic · Permian · GuadalupianMiddle Permian (Wordian)
Named by: Teichert (1966)
Type locality: Amb, Salt Range32.5084°N, 71.9365°E
Thickness: 50-150 m
Lithology: Dark grey to black shale with thin limestone interbeds
Synonyms: Lower Productus Limestone

The basal unit of the Permian Zaluch Group: interbedded sandstone, limestone and shale rich in fusulinid foraminifera, deposited on a mixed clastic-carbonate shelf.

Marine shale sequence deposited during Early Permian transgression. Rich in cold-water Gondwanan fauna. Part of the Zaluch Group.

Fossils

Brachiopods (Productus)Crinoids Bryozoans Foraminifera

Contacts

In the Salt Range 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

Salt Range Kohat Basin Potwar Basin

Basin: Not recorded
Region: Not recorded
Depositional environment: shallow marine, carbonate platform
Coordinates: 32.5084°N, 71.9365°E

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Correlation

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

Economic significance

Other

Produces (with the Wargal Limestone) in the Dhurnal field.

Remarks

A Permian mixed siliciclastic-carbonate unit at the base of the Zaluch Group whose fusulinid-rich limestones record the initial flooding of a Neo-Tethyan carbonate platform on the northwestern margin of the Indian Plate.

Research notes (8)

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 (4)

Waterhouse (2010), citing Mei & Henderson (2002): the Amb Formation (below the Wargal Formation) was assigned a lower Capitanian (Guadalupian) age — considerably younger than the curated Early Permian (Sakmarian–Artinskian) assignment; this discrepancy is flagged for reviewer reconciliation, not applied. The upper Amb includes the Katta Member plant beds with Glossopteris leaves, apparently older than Glossopteris occurrences known elsewhere in the Himalayan ranges.

Waterhouse, J.B. (2010)
Kazmi & Jan (1997): the Amb Formation (type ~5 km SW of Amb village) is up to 80 m of fossiliferous calcareous sandstone, sandy limestone and carbonaceous shale (with thin coals), disconformable on the Sardhai and below the Wargal Limestone; the fusulinids Monodiexodina kattaensis and Codonofusiella laxa are cited for an Early Permian (Late Artinskian) age — OLDER than the curated Middle Permian (Guadalupian), so recorded here as a note rather than an overwrite (the 1997 assignment predates the modern usage).

Kazmi, A.H. & Jan, M.Q. (1997)
Kazmi & Abbasi (2008) CORROBORATES the curated Early Permian age: the fusulinids Monodiexodina kattaensis and Codonofusiella laxa indicate an Early Permian (Late Artinskian) age; the Amb Formation is the lower part of the Zaluch Group (highly fossiliferous calcareous sandstone/sandy limestone with dark carbonaceous shale, thin coal near Amb Village, Glossopteris/Gangamopteris flora; up to 80 m). Resolves the earlier Early-vs-Middle Permian flag in favour of Early Permian.

Kazmi, A.H. & Abbasi, I.A. (2008)
Corrected from "Early Permian (Sakmarian-Artinskian)" (epoch "Cisuralian") to Middle Permian (Wordian, Guadalupian). Both full-text sources assign a Wordian age to the Amb Formation (Mertmann 2003: "A Wordian age is assigned to the Amb Formation"; Wadood et al. 2022). The prior Cisuralian assignment conflated it with the underlying Nilawahan Group.

Mertmann, D. (2003)

Lithology (1)

Hemphill & Kidwai (1973, USGS PP 716-B), Paniala area (Zaluch Group): the Early Permian (Artinskian) Amb Formation is grey/brown thick-bedded calcareous micaceous sandstone with calcareous shale and subordinate argillaceous limestone, carrying fusulinids, bryozoans, brachiopods (athyrids/productids/spiriferids) and crinoids; ~170 ft SE of Paniala, conformable on the Nilawahan Group (= the old 'Lower Productus beds').

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

Stratigraphic contacts (1)

Amb Formation overlies the Sardhai Formation (with a thin basal sandstone) at the base of the Zaluch Group (Mertmann 2003).

Mertmann, D. (2003)

Economic significance (1)

Craig et al. (2018): the Permian Amb Formation (Zaluch Group limestones with thin carbonaceous-shale interbeds) is among the Permian (Tobra-Amb-Wargal) reservoir horizons that have yielded oil and gas in the Potwar Basin.

Craig, J., Hakhoo, N., Bhat, G.M., Hafiz, M., Khan, M.R., Misra, R., Pandita, S.K., Raina, B.K., Thurow, J., Thusu, B., Ahmed, W. & Khullar, S. (2018)

Geological significance (1)

Detailed microfacies (seven types) and outcrop analysis show the Amb Formation as a tide-influenced, subaqueous-delta to middle-shelf mixed siliciclastic-carbonate system deposited under fluctuating sea level, recording two transgressive and two regressive systems tracts across five parasequences; the carbonate platform became established with major rifting on the northern Indian-plate margin (Wadood et al. 2022).

Wadood, B., Khan, S. & Li, H. (2022)

Sources (13)

Malkani, M.S. & Mahmood, Z. (2017). Stratigraphy of Pakistan. Geological Survey of Pakistan, Memoir Vol. 24.
OpenStreetMap contributors and GEOnet Names Server (public geographic gazetteers), used to geolocate named GSP type localities to approximate decimal coordinates.
Shah, S.M.I. (1977). Stratigraphy of Pakistan. Geological Survey of Pakistan, Memoir Vol. 12.
Wadood, B., Khan, S. & Li, H. (2022). Middle Permian Mixed Siliciclastic-Carbonate System on the Northwestern Margin of the Indian Plate, Pakistan: Implications for Paleoclimate and Carbonate Platform Evolution. Acta Geologica Sinica (English Edition).
Mertmann, D. (2003). Evolution of the marine Permian carbonate platform in the Salt Range (Pakistan). Palaeogeography, Palaeoclimatology, Palaeoecology, 191(3-4), 373-384.
Indian Plate Lexicon (indplex.geolex.org), Geological Society of India and international compilation.
Kadri, I.B. (1995). Petroleum Geology of Pakistan. Pakistan Petroleum Limited, Karachi.
Waterhouse, J.B. (2010). Lopingian (Late Permian) stratigraphy of the Salt Range, Pakistan and Himalayan region. Geological Journal, 45, 264-284.
Kazmi, A.H. & Jan, M.Q. (1997). Geology and Tectonics of Pakistan. Graphic Publishers, Karachi.
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.
Gee, E.R. (edited by Gee, D.G.) (1989). Overview of the geology and structure of the Salt Range, with observations on related areas of northern Pakistan. In: Malinconico, L.L. & Lillie, R.J. (eds) Tectonics of the Western Himalayas. Geological Society of America Special Paper 232, 95-112.
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.
Craig, J., Hakhoo, N., Bhat, G.M., Hafiz, M., Khan, M.R., Misra, R., Pandita, S.K., Raina, B.K., Thurow, J., Thusu, B., Ahmed, W. & Khullar, S. (2018). Petroleum systems and hydrocarbon potential of the North-West Himalaya of India and Pakistan. Earth-Science Reviews, 187, 109-185.

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). Amb Formation. In Pakistan Stratigraphy Dataset [Data set]. Zenodo. https://doi.org/10.5281/zenodo.21363991

BibTeX

@misc{stratigraphypk_ambformation,
  author    = {Qudsi, Lareb},
  title     = {{Amb 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/amb-formation (accessed October 29, 2026).

To cite the unit's original definition instead, see: Teichert (1966).

Below · older

Sardhai Formation

Permian

Above · younger

Wargal Limestone