Cenozoic

Mesozoic

Information provided by geoscience team at Ahmadu Bello University, Zaria, Nigeria --see About

Dunganab Formation

Dunganab Fm

Period:

Neogene

Age Interval:

Serravallian – Mid Tortonian

Province:
Sudan E

Type Locality and Naming

Red Sea coastal area of Sudan. The Dungunab Formation is represented by massive salt section ranging in thickness from 300 m in Digna-1 to about 870 m in Durwara-2 well (Eltayib, 2022). It is the equivalent of the South Gharib Formation of Gulf of Suez (Yagoub, 2007).

Reference section: AAPG, 1981; Brown, 1982; Crain, 1986; Chamley, 1989; Asquith et al., 2004; Yagoub, 2007; Eltayib, 2016; Eltayib et al., 2019; Eltayib, 2022

[Figure 1. Index map of the Red Sea showing extent of the Red Sea Basin total petroleum system (from Lindquist, 1998).]

[Figure 2. Syn- and Post-Rift Red Sea Stratigraphy - Oligocene to Recent (from Lindquist, 1998)]

[Figure 3. Pre-Rift Red Sea Stratigraphy - Precambrian to Oligocene (from Lindquist, 1998).]

[Figure 4. Index map of the Red Sea region showing generalized geology and discussed locations (after Mitchell and others, 1992, extracted from Lindquist, 1998).]

[Figure 5. Lithostratigraphic Column of the Study Area (Modified After Eltayib, 2016, from Eltayib et al., 2019).]

[Figure 6. Stratigraphic column for the Sudanese Red Sea, based on surface geology and limited coastal exploration wells (after Bunter, 1989). Extracted from]

Lithology and Thickness

It is composed of a very thick sequence of evaporites (Halite and anhydrite) with thin beds of shales with a thick-ness in ranges of 300-900m. The Dungunab Formation is represented by massive salt Formation ranging in thickness from 300m in Dig-na-1 to about 870m in Durwara-2 well (Eltayib, 2016; Eltayib et al., 2019). It is composed of a very thick sequence of evaporites (rock salt and anhydrite) with thin beds of shales. The thickness ranges from 300 m-900 m [AAPG, 1981; Brown, 1982; Chamley, 1989; Crain, 1986; Asquith et al., 2004].

Lithology Pattern:

Halite

Relationships and Distribution

Lower contact

Belayim Fm, conformably

Upper contact

Zeit Fm, conformably

Regional extent

Red Sea coastal area of Sudan.

GeoJSON

{"type":"Feature","geometry":{"type":"MultiPolygon","coordinates":[[[[37.95,18.81],[39.04,17.41],[39.42,16.51],[39,16.11],[38.65,16.25],[38.17,17.25],[37.2,17.85],[36.6,19.03],[37.25,19.29],[37.95,18.81]]]]}}

Fossils

Age

Serravallian – Mid Tortonian

Age Span:

Beginning stage:

Serravallian

Fraction up in beginning stage:

0.33

Beginning date (Ma):

13.10

Ending stage:

Tortonian

Fraction up in the ending stage:

0.5

Ending date (Ma):

9.44

Depositional setting

Saline to extremely hypersaline (Elkareem et al., 2022)

Depositional pattern:

Additional Information

Compiler:

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

Bunter, M.A.G. and Abdel Magid, A.E.M. (1989): The Sudanese Red Sea: New Development in Stratigraphy and Petroleum Geological Evolution. Jour. Petroleum Geology, 12: 145-166. https://doi.org/10.1111/j.1747-5457.1989.tb00230.x

Elkareem, E.M.I.A., Osman, W.R., Ferguson, A.J., Warren, J.K. and Mohamed, N.E. (2022): New Evidence of the Holokinetic Sequences around Suakin-1 and -2 in the Sudanese Red Sea Area Using Integrated Geophysical Interpretation. International Journal of Geosciences, 13: 483-497. https://doi.org/10.4236/ijg.2022.136026

Eltayib, S.H.M.A., Abdelrahman, E.S.M., Ibrahim, A.S.M., Al-Imam, O.A.O.. (2019): Sedimentary petro graphic characteristics of Zeit Formation (Suakin-1 Well) in Sudanese Red Sea Basin. Int Jour Advanced Geosciences. 7: 10-17.

Yagoub, A.M. (2007): Preliminary sequence stratigraphy and tectonic evolution of the Tokar Delta, (Southern Sudanese Red Sea). Qatar Univ. Sci . J. 27: 85- 98.