Mesozoic • Triassic–Jurassic formation In GSP lexicon

Saidu Formation

Triassic–Jurassic

Northern Indus Suture · Malakand

Part of Alpurai Group

Triassic–Jurassic in the time scale →

Cited in 6 sources Last reviewed Aug 10, 2026

Unit summary

Rank: formation
Status: Published
Age: Mesozoic · Triassic–JurassicTriassic–Jurassic
Named by: Kazmi et al. (1986)
Type locality: Nikanai Ghar range, southern Swat
Thickness: up to ~1000 m
Lithology: Calcareous and pelitic schist (the Saidu Schist).
Synonyms: Not recorded

A Triassic–Jurassic schist unit (the Saidu Schist) of the upper Alpurai Group.

The Saidu Formation is named by Kazmi et al. (1986) for a thick sequence of grey to dark-grey calcareous and pelitic schist (graphitic and chloritic) exposed south of the MMT in the vicinity of Saidu and elsewhere in the Swat area, with a thrusted contact against melanges of the Indus Suture zone. About 30 km south of Saidu the Saidu schist is replaced by the Nakanai Ghar formation (named after the Nikanai Ghar range in southern Swat by Palmer-Rosenberg 1985 for marble, dolomitic marble, schist and quartzite), which overlies the Kashala formation and is tentatively assigned a Late Triassic to Jurassic age (Pogue et al. 1962).

Fossils

Not recorded

Contacts

In the Swat–Malakand column

MetamorphicMixedFossils 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

Swat–Malakand

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

Correlation

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

Economic significance

Not recorded

Remarks

A schist unit of the upper Alpurai Group lying between the Kashala Formation and the Nikanai Ghar Formation; part of the Mesozoic (Triassic–Jurassic) cover of the Swat Nappe.

Research notes (6)

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 (2)

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 lists this unit as 'Saidu schist'.

Shah, S.M.I. (2009)
DiPietro et al. (1993) attribute the name and type section (road cuts ~1 km north of Saidu) to Martin et al. (1962), with Kazmi et al. (1984); formalised at formation rank by DiPietro (1990). (Canonical retains 'Kazmi et al. (1986)'.)

DiPietro, J.A., Pogue, K.R., Lawrence, R.D., Baig, M.S., Hussain, A. & Ahmad, I. (1993)

Age & correlation (1)

CONFIRMED by DiPietro et al. (1993, full text): the Saidu Formation of the Alpurai Group (Triassic or younger), interpreted as shelf drowning beneath the MMT suture melange. Corroborates the Triassic-Jurassic age.

DiPietro, J.A., Pogue, K.R., Lawrence, R.D., Baig, M.S., Hussain, A. & Ahmad, I. (1993)

Thickness (1)

Thickness surfaced from the geological-significance note: the Saidu Formation is up to ~1000 m of graphitic phyllite (DiPietro et al. 1993).

DiPietro, J.A., Pogue, K.R., Lawrence, R.D., Baig, M.S., Hussain, A. & Ahmad, I. (1993)

Geological significance (2)

DiPietro et al. (1993): graphitic phyllite (up to ~1000 m) interpreted as recording drowning of the shelf beneath the advancing Main Mantle Thrust melange; may correlate with the Lamayuru Formation of western India.

DiPietro, J.A., Pogue, K.R., Lawrence, R.D., Baig, M.S., Hussain, A. & Ahmad, I. (1993)
Anczkiewicz et al. (1998): the Saidu Schists (graphitic phyllites and marbles) are the uppermost Indian-plate unit in Lower Swat and the only one not reaching amphibolite grade (greenschist facies only), assigned Triassic or younger. Their basal contact is a normal shear zone: the grade contrast with the amphibolite-grade Alpurai Schists below implies a minimum 4-5 km of vertical offset, i.e. emplacement by extensional (normal) faulting on the reactivated suture.

Anczkiewicz, R., Burg, J.-P., Hussain, S.S., Dawood, H., Ghazanfar, M. & Chaudhry, M.N. (1998)

Sources (6)

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.
DiPietro, J.A., Pogue, K.R., Lawrence, R.D., Baig, M.S., Hussain, A. & Ahmad, I. (1993). Stratigraphy south of the Main Mantle Thrust, Lower Swat, Pakistan. In: Treloar, P.J. & Searle, M.P. (eds), Himalayan Tectonics. Geological Society, London, Special Publications, 74, 207-220.
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.
Anczkiewicz, R., Burg, J.-P., Hussain, S.S., Dawood, H., Ghazanfar, M. & Chaudhry, M.N. (1998). Stratigraphy and structure of the Indus Suture in the Lower Swat, Pakistan, NW Himalaya. Journal of Asian Earth Sciences, 16(2-3), 225-238.

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

BibTeX

@misc{stratigraphypk_saiduformation,
  author    = {Qudsi, Lareb},
  title     = {{Saidu 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/saidu-formation (accessed October 29, 2026).

To cite the unit's original definition instead, see: Kazmi et al. (1986).

Below · older

Kashala Formation

Triassic

Above · younger

Nikanai Ghar Formation