Cenozoic • Paleogene formation In GSP lexicon

Khojak Formation

Late Eocene to Early Miocene, mainly Oligocene (Priabonian-Chattian; ~35.8-23.0 Ma)

Cited in 10 sources Last reviewed Aug 2, 2026

Unit summary

Rank: formation
Status: Published
Age: Cenozoic · Paleogene · Late Eocene to Early Miocene (mainly Oligocene)Late Eocene to Early Miocene, mainly Oligocene (Priabonian-Chattian; ~35.8-23.0 Ma)
Named by: Vredenburg (1909)
Type locality: Nauroz, 30 km NE of Kharan (Kalat)
Thickness: 900-1500 m (around the type locality); members up to several thousand m
Lithology: Shale, sandstone and siltstone of mainly turbiditic and deltaic origin (Katawaz remnant ocean); locally carbonaceous with lignite lenses.
Synonyms: Khojak Shale

A thick Oligocene flysch-molasse succession of shale, sandstone and siltstone of turbiditic and deltaic origin, deposited in the Katawaz remnant ocean. Subdivided into the lower Murgha Faqirzai member (shale-dominated, ~1200 m at its type section) and the upper Shaigalu member (sandstone and shale, up to ~6000 m estimated). Widely exposed in the Axial Belt and the Chagai-Raskoh Magmatic Province. Named by Vredenburg (1909); type locality at Nauroz, 30 km NE of Kharan, Kalat.

Fossils

Lepidocyclina dilatata Nummulites fichteli Nummulites intermedius Nummulites vascus Nummulites atacicus Assilina granulosa Dictyoconoides cooki

Contacts

In the Zhob-Muslim Bagh column

SandstoneShale / mudIgneousLimestoneFossils recordedConformable

Band colour = period; texture = dominant rock type. Lines between bands mark the contact type. 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.

Constituent units

Formations that make up this formation, in stratigraphic order (youngest at top, as in the column).

Distribution & setting

Zhob-Muslim Bagh Chagai Hills

Basin: Not recorded
Region: Not recorded
Depositional environment: deltaic, submarine fan, deep marine
Coordinates: Not recorded

Correlation

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

Economic significance

Coal & lignite

Locally carbonaceous, with lenses of lignite.

Remarks

The Oligocene–Early Miocene flysch/molasse of the Khojak–Pishin (Katawaz) belt, exceeding ~6,300 m in the Chaman area. Named after the Khojak Pass near Chaman and first mapped as the 'Khojak Shale' by Vredenburg (1909); divided into a lower shale-dominant Murgha Faqirzai Member and an upper sandstone-dominant Shaigalu Member (Hunting Survey Corporation 1960), together deposited in a wave-modified, fluvial-dominated delta system.

Sources (9)

Indian Plate Lexicon (indplex.geolex.org), Geological Society of India and international compilation.
Malkani, M.S. (2020). Revised Stratigraphy and Mineral Resources of Balochistan Basin, Pakistan: An Update. Open Journal of Geology, 10, 784-828.
Shah, S.M.I. (2009). Stratigraphy of Pakistan. Geological Survey of Pakistan, Memoir Vol. 22.
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.
Kakar, D.M., Kasi, A.K., Kassi, A.M., Friis, H., Mohibullah, M. & Khan, S. (2016). Petrography and whole-rock geochemistry of the Oligocene–Miocene Khojak Formation, Khojak-Pishin Belt, Pakistan: implications on provenance and source-area weathering. Journal of Himalayan Earth Sciences, 49(2).
Yaseen, W., Khan, A.S., Sohail, K., Farooq, U., Usman, M. & Ghani, M. (2019). Modal composition and provenance of Shaigalu Sandstones, Pishin-Katawaz Basin, northern Balochistan, Pakistan. Bahria University Research Journal of Earth Sciences (BURJES), 4(2), 70-77.
Waliullah, Khan, J.A. & Akhtar, W. Preliminary geology and mineral potential of the Karezat and Barshor quadrangles (toposheets 34 N/6 and 5), district Pishin, Balochistan. Geological Survey of Pakistan, Quetta (abstract).
Kasi, A.K., Kassi, A.M., Umar, M., Manan, R.A. & Kakar, M.I. (2012). Revised lithostratigraphy of the Pishin Belt, northwestern Pakistan. Journal of Himalayan Earth Sciences, 45(1), 53-65.

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.

Cite this unit

APA

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

BibTeX

@misc{stratigraphypk_khojakformation,
  author    = {Qudsi, Lareb},
  title     = {{Khojak 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/khojak-formation (accessed September 5, 2026).

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

Below · older

Kharan Formation

Paleogene

Above · younger

Hinglaj Formation

Neogene

Referenced in other successions

Overlain by Dasht Murgha Group