Fiqa’ Fm

A.D.P.C. well Murban No. 44, lat. 23°10’22” N. long. 53°20’35” E, elevation 133.5 m (438 ft), completed 20.9.1965, between drilled depths 1653 and 2003 m (5422 and 6571 ft). A.J. Standring and E. Hart (unpublished report). Shargi Member is known in onshore Qatar only from Dukhan Well No. 51 (Juh-1), where it overlies the Halul Formation and yields a typical Campanian planktonic microfauna.

Synonym: “Shargi Formation”, Dominguez, 1965. “Upper Shale”, Hajash, 1967. “Aruma marl”, Fox and Brown, 1968.

Reference Section:

Top. 1. Light grey, very chalky marl grading into a white chalk with, locally, rare, slightly silty shale partings. Interbeds of chalky, foraminiferal, lime wackestones, containing fine skeletal debris. 39 m (128 ft). 2. Dark grey-green, calcareous shale and light grey, chalky marl grading into a white chalk. Thin interbeds of buff detrital, chalky, foraminiferal lime wackestone containing shell debris and light grey argillaceous limestone, 42 m (137 ft). 3. Limestone, light buff, slightly argillaceous, chalky lime wackestone, particles consisting of smaller foraminifera and shell and echinoid debris. 49 m (161 ft). 4. Shale, dark grey, slightly calcareous, with chalky marl. 18 m (60 ft). 5. Pale buff, chalky to locally argillaceous limestone interbedded with dark grey, sometimes calcareous, shale, which tends to predominate in the lowest 40 ft. 35 m (116 ft). 6. Pale grey to buff, slightly chalky foraminiferal wackestone with particles consisting of shell debris; interbeds of grey-green shale. 54 m (178 ft). 7. Dark grey-green shale grading into grey marl with thin interbeds of light grey-buff, fine lime wackestone. 30 m (100 ft). 8. Shale, dark grey-green. 71 m (233 ft). 9. Limestone, light grey, argillaceous, locally pyritic. 11 m (36 ft). Base. Thickness is 350 m (1149 ft). The Fiqa’ Formation includes two distinct members: 1. The Arada Member (units 1 to 7 of the type section which takes its name from a locality some 33 km S.S.E. of the type locality. This shallow-water unit is probably the equivalent of the shallow-water facies carrying Monolepidorbis sanctae-pelagiae reported from the Lower Aruma of Saudi Arabia (R.W. Powers, 1968). 2. The Shargi Member (units 8 and 9 of the type section) is named from Id-al-Shargi, Qatar, where it is the only member of the Fiqa’ Formation present between the Simsima and Halul Formations. Comparable facies are present in the Lower Aruma of Saudi Arabia. This description is included in the Qatar Lexicon because the Fiqa’ Formation has been recognized in one well section to the south of the Dukhan Field in onshore Qatar. The following sequence occurs in Dukhan Well No. 51 (formerly Juh-1) between the Simsima and Halul Formations: 1. Limestone, bioclastic wackestone and packstone yielding Monolepidorbis sanctae-pelagiae, Rotalia trochidoformis. 17 m (55 ft). 2. Shale, blue-grey, containing planktonic foraminifera including Globotruncana arca, Gl. Lapparenti, Gl. gr. stuarti. 58 m (190 ft). Unit 1 represents the ‘Arada Member and Unit 2 the Shargi Member of the Fiqa’ Formation.

In 1. Monolepidorbis douvillei Astre, Rotalia aff. trochidoformis, aff. Archaecyclus sp. In 2. M. douvillei, R. aff. trochidiformis, aff. Archaecyclus sp., Ataxophagium sp. In 3. M. douvillei, R. aff. trochidiformis, Rotalia sp., aff. Archaecyclus sp., Bryozoa and echinoid debris. In 4 and 5. M. douvillei, R. aff. trochidiformis. In 6. M. douvillei, M. sanctae-pelagiae Astre, rare Globotruncana sp., crab debris, echinoid spines, Bryozoa, rudist fragments, fish remains. In 7. M. sanctae-pelagiae, Pseudedomia aff. multistriata. In 8 and 9. Globotruncana gr. Fornicata Plummer, Globotruncana arca arca (Cushman), Globotruncana arca (Cushman) caribica Gandolfi, Globotruncana globigerinoides Brotzen, Globotruncana cf. concavata (Brotzen), Globotruncana contusa (Cushman), Rugoglobigerina beldingi Gandolfi, Planoglobulina sp., Gumbelina spp., Ostracoda including Bairdoppilata sp., Cytherella sp., Paracypris glabrans ms., Brachycythere wellingsi ms.

Shargi Member yields a typical Campanian planktonic microfauna.