Khuff Fm

Period:

Permian

Age Interval:

Late Permian

Province:
Qatar

Type Locality and Naming

In Saudi Arabia. M. Steineke, R.A. Bramkamp and N.J. Sander, 1958. The type section is in Saudi Arabia.

Synonym: “Bahrain Unit A”, Milne, 1959. “Khuff”, Dominguez, 1965.

Reference Section:

Q.P.C. Well Dukhan No. 65, lat. 25°27’38” N, long. 50°47’13” E, elevation 42 m (140 ft), completed 21.1.1960, between drilled depths 2895 and 3394 m (9494 and 11132 ft).

Lithology and Thickness

Top. 1. Dolomite, grey to buff, dense, with thin beds showing relict pellety, oolitic nature. Generally fine, dense, but some saccharoidal. 81 m (267 ft). 2. Dolomitic limestone grading to dolomite, with well-preserved original pellety, oolitic texture. 31 m (101 ft). 3. Dolomite, dark grey, occasional relict pellety and oolitic horizons. Nodules and thin beds of anhydrite in lower part. 134 m (438 ft). 4. Anhydrite with interbedded dolomite, anhydritic. 15 m (50 ft), 5. Dolomite, grey with occasional relict limestone textures. Nodules and streaks of anhydrite. 238 m (782 ft). Base. Its thickness is 499 m (1638 ft).

Lithology Pattern:

Dolomitic limestone

Relationships and Distribution

Lower contact

WajidSandstones Fm; nature of contact not established. At junction of lowest dolomite of the Khuff, above, with grey-green shales and marls of the Wajid, below.

Upper contact

Suwei Fm; contact believed to be conformable. Located where the highest dolomite of the Khuff is overlain by grey and brown shales of the basal Suwei.

Regional extent

Deep wells in the Dukhan field and Q.P.C. Well Musaiymir No. 1, in eastern Qatar. Also in deep wells in offshore Qatar and Bahrain. Widespread at outcrop and subsurface in Saudi Arabia and Oman.

GeoJSON

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Fossils

Hemigordius sp., Padangia sp., Geinitzina cf. ovata Lange, G.sp., Pachyphloia sp., Ozowainella sp., and ? Permo-calculus sp., have been identified from units 2 to 5.

Age

The above listed fossils are not age diagnostic but are typical of the Khuff Fm of Arabia, which has been firmly dated as Late Permian in Saudi Arabia.

Age Span:

Beginning stage:

Wuchiapingian

Fraction up in beginning stage:

0.0

Beginning date (Ma):

259.55

Ending stage:

Wuchiapingian

Fraction up in the ending stage:

1.0

Ending date (Ma):

254.24

Depositional setting

Depositional pattern:

Additional Information

The Khuff Formation marks the beginning of widespread shallow-water limestone deposition which typifies much of the subsequent sedimentary history of Arabia east of the Shield area. It was laid down in a widespread, shallow, transgressive sea during an interlude in the period of clastic deposition which typified most of the Palaeozoic.

Compiler:

Jacques LeBlanc (2021), transcribed and translated from Stratigraphic Lexicon Qatar Peninsula by W.Sugden and A.J. Standring, 1972