Cenozoic • Neogene formation In GSP lexicon

Chatti Formation

Early Pleistocene (Gelasian; ~2.58-1.80 Ma)

Balochistan Basin · Makran-Siahan Basin, Wazhdad Arc And Mashkel/Kharan Basin

Cited in 6 sources Last reviewed Jul 31, 2026

Unit summary

Rank: formation
Status: Published
Age: Cenozoic · Neogene · Early PleistoceneEarly Pleistocene (Gelasian; ~2.58-1.80 Ma)
Named by: HSC (1961)
Type locality: Makran Flysch Province, Balochistan Basin25.3000°N, 62.1300°E
Thickness: over 1000 m
Lithology: Clayey sandstone.
Synonyms: Not recorded

A Pliocene coastal-Makran mudstone near Gwadar, among the youngest marine deposits of the wedge.

Chatti Formation is after the locality of Chatti (31 K/3) about 17 miles north west of Gawader (HSC, 1961). These rocks were also included in the "Upper Mudstone" of Khan (1951). It is a part of Makran series paleontologically defined by Vredenburg (1909; p. 299-300). It consists of mostly mudstone which is interbedded with siltstone or fine grained sandstone and marl. The Ormara is the synonym of Chatti because Ormara is mapped in the eastern part of southern Makran coastal areas where Chatti formation is not mapped and distinction between Ormara and Chatti mudstone is also difficult in the western part also (HSC, 1961). Its age is Pliocene.

Fossils

Not recorded

Contacts

In the Makran Coast column

Shale / 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

Makran Coast

Basin: Balochistan Basin
Region: Makran-Siahan Basin, Wazhdad Arc And Mashkel/Kharan Basin
Depositional environment: marine, shelf
Coordinates: 25.3000°N, 62.1300°E

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Correlation

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

Economic significance

Not recorded

Remarks

A Pliocene mudstone of the coastal Makran (Gwadar area), part of the youngest, regressive marine fill of the accretionary wedge.

Research notes (4)

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 (1)

Attested in Shah (2009), Geological Survey of Pakistan Memoir 22, which describes it as the Chatti mudstone member, upper member of the Hinglaj Formation (adopted from Hunting Survey 1961). Adds the definitional GSP/SCP lexicon citation.

Shah, S.M.I. (2009)

Age & correlation (1)

Age refined to Early Pleistocene (Gelasian) per the Indian Plate Lexicon (compiler N.K. Siddiqui); conformably overlies Hinglaj or Talar Fm and is unconformably overlain by the Gwadar Fm.

Indian Plate Lexicon (indplex.geolex.org), Geological Society of India and international compilation.

Geological significance (2)

Kazmi & Jan (1997) RANK FLAG: the book treats this as the upper 'Chatti Mudstone Member' of the Hinglaj Formation (more calcareous/marly mudstone; Pleistocene), not a stand-alone formation.

Kazmi, A.H. & Jan, M.Q. (1997)
Kazmi & Abbasi (2008) REVISES the earlier rank flag: the book treats the Chatti as its own formation — the 'Chatti Formation' of HSC (1960), for shelf-to-slope calcareous mudstone-siltstone around Chatti Village (25 km NW of Gwadar), conformably overlying the Talar Formation (Plio-Pleistocene) — not as a member of the Hinglaj Formation. The dataset's formation rank is supported here; the earlier 'Chatti Mudstone Member of the Hinglaj Formation' framing (Kazmi & Jan 1997) is superseded.

Kazmi, A.H. & Abbasi, I.A. (2008)

Sources (6)

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.
Indian Plate Lexicon (indplex.geolex.org), Geological Society of India and international compilation.
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.

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

BibTeX

@misc{stratigraphypk_chattiformation,
  author    = {Qudsi, Lareb},
  title     = {{Chatti 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/chatti-formation (accessed October 29, 2026).

To cite the unit's original definition instead, see: HSC (1961).

Below · older

Talar Formation

Neogene

Above · younger