Taqa Fm

Period:

Neogene

Age Interval:

Latest Oligocene – Miocene, On1

Province:
Oman

Type Locality and Naming

Taqah area (E54°24’, N17° 02’), and west of Ras Raisut (E54°00’, N16°56’), Dhofar. The thickness in the type area is ca. 1,100–1,400 m. Additional reference sections are Barik-8 and Nimr-143 Column: Oman Subsurface; Lowermost formation in the Fars Gr

Synonym: Synonymous with Fars Gr in South and Central Oman, because this facies extends to the base of the Fars Gr.

Lithology and Thickness

Limestone to Reef limestone. A dominantly carbonate sequence, including chalky and porous marine, sometimes reefal, limestones. It features strongly recrystallized fossiliferous limestone and calcareous dolomite.

Lithology Pattern:

Reef limestone

Relationships and Distribution

Lower contact

It unconformably overlies the Hadhramaut Gr units and, in Dhofar, Mesozoic units. Priabonian through early Chattian are absent.

Upper contact

It passes up with transition into undifferentiated Fars Gr clastics and evaporites (Dhulaima Fm equivalent). However, the Dhulaima Fm is essentially coeval and is dominate in North Oman.

Regional extent

"Hughes Clarke (1988) stated that the Taqa Formation is developed mainly to the south, in Dhofar, along the southeastern coasts, but also in the Lekhwair area of North Oman. This reflects the areas with most marine influx during the Oligocene – Miocene. The flat-lying thin limestone forming the surface of the Jiddat al Harasis plains (Central Oman) is a deposit of the global high-stand of sea level during the Middle Miocene. However, according to Mohammed et al. (1997) it is mostly confined to South and Central Oman."

GeoJSON

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Fossils

" The Taqa has a distinct fauna of Miocene age. … Biozone F78 (Peneroplis farsensis, previously FZV, Miocene) with Late Oligocene palynofloras (not zoned) in southern Oman, and Biozone F77 (Miogypsina sp., Nummulites intermedius, previously FZU, Oligocene)"

Age

Late Chattian – Burdigalian for display purposes to allow showing coeval Dhulaima Fm "above" it. True span is "Oligocene – Miocene, ca. 33–5.3 Ma. The Taqa has a distinct fauna of Miocene age. Although Mohammed et al. (1997) stated that there is no evidence of Oligocene faunas in southern Oman, a Late Oligocene age has been noted via palynological analysis and there are rare records of Biozone F77 in the south. Note also there are well-documented Early Oligocene vertebrate discoveries in Dhofar (Thomas et al., 1999, and related papers). Sharland et al. (2004, see also 2001) place their renumbered Early Miocene MFS Ng10, and their Oligocene MFS Pg50 (previously Ng10), MFS Pg40 and MFS Pg30 surfaces within the Taqa Formation of southern Oman."

Age Span:

Beginning stage:

Chattian

Fraction up in beginning stage:

0.5

Beginning date (Ma):

25.16

Ending stage:

Burdigalian

Fraction up in the ending stage:

1.0

Ending date (Ma):

15.99

Depositional setting

Shallow-marine (mostly very shallow to restricted), including reefal and lagoonal environments.

Depositional pattern:

Additional Information

Compiler:

From Forbes, G.A., Hansen, H.S.M., and Shreurs, J., 2010. Lexicon of Oman: Subsurface Stratigraphy. Gulf Petrolink, 371 pp. (plus enclosures and CD); and Middle East Geological Timescale 2008 Al-Husseini, Journal of Middle East Petroleum Geosciences v 13. no. 4