Mesozoic • Jurassic Superseded In GSP lexicon

Loralai Formation

Early to Middle Jurassic

Part of Sulaiman Group, Shirinab Formation, Alozai Group

Jurassic in the time scale →

Cited in 10 sources Last reviewed Aug 2, 2026

Unit summary

Rank: Not recorded
Status: Published
Age: Mesozoic · Jurassic · Late Triassic, may extend up to Middle Jurassic (Bajocian)Early to Middle Jurassic
Named by: Hunting Survey Corporation (1960)
Type locality: Loralai, Balochistan30.3669°N, 68.6001°E
Thickness: 300-500 m
Lithology: Limestone, shale, marl
Synonyms: Loralai Limestone (HSC 1960; largely replaced by the Shirinab Formation, Fatmi 1977)

Nomenclature

Superseded name. First defined by Hunting Survey Corporation (1960).

Superseded by Shirinab Formation →.

Browse all alternative & superseded names →

A Jurassic limestone of the Loralai area whose old name has mostly been replaced by the Shirinab Formation.

Named after Loralai. Marine sequence in Sulaiman basin representing open marine shelf conditions. Important for petroleum exploration.

Fossils

Ammonites Belemnites Bivalves Foraminifera

Contacts

In the Sulaiman Fold Belt column

Shale / 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: Not recorded
Region: Not recorded
Depositional environment: marine
Coordinates: 30.3669°N, 68.6001°E

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Correlation

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

Economic significance

Metals & minerals

The Jurassic Loralai Limestone hosts fluorite veins (Gadebar and Daman Ghar ranges, Loralai district) along faults and fractures; a building-limestone source.

Remarks

A Jurassic limestone of the Loralai–Zhob area; the name 'Loralai Limestone' was an early Hunting Survey Corporation mapping unit now largely subsumed into the Jurassic Shirinab Formation.

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)

'Loralai Limestone' (HSC 1960) has largely been replaced by the Shirinab Formation (Fatmi 1977).

Kazmi, A.H. & Jan, M.Q. (1997)
USGS OFR 94-689 records that the Loralai Formation, formerly a member of the Shirinab Formation (Williams 1959; Fatmi 1977), was elevated to formational status as the upper formation of the Alozai Group (Loralai over Spingwar) by Fatmi (in press).

Maldonado, F., Khan, S.H. & Mengal, J.M. (1994)

Lithology (1)

Nizami, Ashraf, Ata Razi & Hamid (2010), Khidirzai Nala section (Bargha Shirani, Western Sulaiman Range, District Zhob): the Middle Jurassic Loralai Formation carbonates comprise intraclastic rudstones and grainstones, skeletal/ooidal/pisoidal/peloidal grainstones and skeletal to unfossiliferous mudstones, cut by a range of early-to-late diagenetic cements.

Nizami, A.R., Ashraf, M., Ata Razi, S.M.S. & Hamid, K. (2010)

Thickness (1)

Type-section thickness (Shah, 2009): 250 m Zamari Tangi; 360 m Mara Tangi; 150 m Tazi Kach. Type locality: Zamari Tangi (proposed type locality). Recorded from the GSP lexicon (Memoir 22); the existing thickness field is retained.

Shah, S.M.I. (2009)

Economic significance (2)

Razzaq Manan et al. (2024): the Jurassic Loralai Limestone, together with the Chiltan Limestone, is part of the frontier Triassic–Jurassic carbonate petroleum play of the Sulaiman Fold-Thrust Belt; several fracturing phases and mesogenetic (burial) alteration have enhanced effective secondary porosity, improving reservoir quality.

Razzaq Abdul Manan, Kassi, A.M., Friis, H., Kasi, A.K., Ali, S.H., Farooqui, M.A. & Kakar, M.I. (2024)
Nizami et al. (2010): the Loralai Formation has oil-and-gas reservoir potential in the Western Sulaiman Range - well-developed grainstone microfacies with secondary dissolution, moldic and vuggy porosity.

Nizami, A.R., Ashraf, M., Ata Razi, S.M.S. & Hamid, K. (2010)

Sources (9)

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. (2010). Updated Stratigraphy and Mineral Potential of Sulaiman Basin, Pakistan. Sindh University Research Journal (Science Series), 42(2), 39-66.
Maldonado, F., Khan, S.H. & Mengal, J.M. (1994). Preliminary Geologic Map of Parts of Loralai, Sibi, Quetta, and Khuzdar Divisions, Balochistan Province, West-Central Pakistan. U.S. Geological Survey Open-File Report 94-689, 20 p., 1 sheet.
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.
Razzaq Abdul Manan, Kassi, A.M., Friis, H., Kasi, A.K., Ali, S.H., Farooqui, M.A. & Kakar, M.I. (2024). Deposition and diagenesis of the Triassic-Jurassic limestone successions of the northwestern passive margin of the Indian plate, Sulaiman Fold-Thrust Belt, Pakistan. Carbonates and Evaporites, 39, 104.

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

BibTeX

@misc{stratigraphypk_loralaiformation,
  author    = {Qudsi, Lareb},
  title     = {{Loralai 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/loralai-formation (accessed October 29, 2026).

To cite the unit's original definition instead, see: Hunting Survey Corporation (1960).

Above · younger

Chiltan Limestone

Jurassic