Cenozoic

Mesozoic

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Hebeika Formation

Hebeika Fm

Period:

Cretaceous

Age Interval:

Barremian-Aptian

Province:
Sudan E

Type Locality and Naming

Khartoum Basin, central Sudan. AAF-2 is considered type well for the Hebeika Formation, because it was not encountered in well AAF-1.

Reference: Awad (1994), A. Gibreel (2015)

[Fig. 1: Khartoum Basin is #8 on map (Fig.3 in Awad, 1994)]

[Fig. 2: Khartoum Basin stratigraphy and depositional sequences (pg. 17 in A. Gibreel, 2015)]

Lithology and Thickness

"The Hebeika Formation consists predominantly of interbedded tuffaceous claystone and sandstone; "weathered” volcanic basalt may also occur (Sun Oil, unpubl. rep ). Basal sandstones occur locally; these are primarily unlithified, coarse to very coarse, often argillaceous and the grains are subrounded and subangular." (Awad, 1994). It is ca. 390 m thick in well AAF-4, and 273 m in well AAF-2.

Lithology Pattern:

Sandy claystone

Relationships and Distribution

Lower contact

Unconformity (latest Hauterivian is a hiatus) onto the Sawagir Fm

Upper contact

Major unconformity (Albian is missing) to the overlying Mansur Fm

Regional extent

Khartoum Basin, central Sudan.

GeoJSON

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Fossils

Spores (Geicheniidites senonicu); Pollen (Dicheiropollis etruscus, Spheripollenites subgranulatus, Spheripollenites scabratus, Exesipollenites scabratus, Callialasporites segmentatus, Perinopollenites elatoides); Freshwater alga (Celyphus rallus, Leisphaeridia sp.), (Awad, 1994)

Age

Barremian-Aptian according to A. Gibreel (Ministry of Petroleum and Gas, 2015), used here; but Awad (1994) assigned it a "?Latest Neocomian".

Age Span:

Beginning stage:

Barremian

Fraction up in beginning stage:

0.0

Beginning date (Ma):

126.50

Ending stage:

Aptian

Fraction up in the ending stage:

1.0

Ending date (Ma):

113.20

Depositional setting

Fresh to brackish water lacustrine (Awad, 1994)

Depositional pattern:

Additional Information

Compiler:

Enam O. Obiosio, Solomon Joshua Avong and Henry Nasir Suleiman (2024) - Stratigraphic Lexicon compiled from the following publications:

Awad, M.Z., 1994. Stratigraphic, Palynological and Paleoecological Studies in the East-Central Sudan (Khartoum and Kosti Basins), Late Jurassic to Mid-Tertiary. Berliner Geowiss. Abh. 161: 163 pp.

Gibreel, Ahmed (Section Head G&G Studies, Ministry of Petroleum and Gas, Republic of Sudan(, 2015. Hydrocarbon potential and resources in Sudan. [Slide presentation at UNCTAD, 17^th Africa OILGASMINE, Khartoum, 23-26 Nov 2015]. https://unctad.org/system/files/non-official-document/17OILGASMINE%20Ahmed%20Gibreel%20Ahmed%20El-Amain%20S1.pdf