Volcanics-BlueNile Fm
Period:
Paleogene, Neogene, Quaternary
Age Interval:
Late Oligocene – Recent
Province:
Sudan E
Type Locality and Naming
Blue Nile Basin, Southeast Sudan and Northwest Ethiopia. [No official name; but "BlueNile" appended to enable linking of website-page in this online Lexicon.]
Reference: Jain and Singh, 2019; Jain et al. 2022.
[Fig. 1: General stratigraphy of the Blue Nile basin, with major lithological characteristics and age assignment (from Jain and Singh, 2019).]
Lithology and Thickness
Massive basalt, trachyte, rhyolite, with beds of tuff (welded), paleosols, and lacustrine sediments; 5500 m (Jain and Singh, 2019)
Lithology Pattern:
Lava
Relationships and Distribution
Lower contact
unconformably onto Debre Lebanos Fm. [Late Cretaceous through lower Oligocene is missing.]
Upper contact
modern surface
Regional extent
Blue Nile Basin, Southeast Sudan and Northwest Ethiopia
GeoJSON
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Fossils
Age
Late Oligocene – Recent (Jain and Singh, 2019)
Age Span:
Beginning stage:
Chattian
Fraction up in beginning stage:
0.00
Beginning date (Ma):
27.29
Ending stage:
Holocene
Fraction up in the ending stage:
1.00
Ending date (Ma):
0.00
Depositional setting
Depositional pattern:
Additional Information
Compiler:
Enam O. Obiosio, Solomon Joshua Avong and Henry Nasir Suleiman (2024) - Stratigraphic Lexicon compiled from the following publications:Jain S., Singh A. (2019): First calcareous nannofossil record from the Jurassic strata exposed in the Blue Nile Basin (Ethiopia). Jour. African Earth Sci. 158: 103553.
Jain, S., Mullugetta, M., Benzaggagh, M., Salamon, M. A., & Schmerold, R. (2022). Discovery of chitinoidellids and calpionellids from the Blue Nile Basin and the Jurassic‐Cretaceous boundary in Ethiopia. Cretaceous Research, 132, 105112. https://doi.org/10.1016/j.cretres.2021.105112.