Adigrat Fm
Period:
Jurassic
Age Interval:
Pliensbachian – Bajocian
Province:
Sudan E
Type Locality and Naming
Blue Nile Basin, Southeast Sudan and Northwest Ethiopia
Synonym: Adigrat Sandstone
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
700m. Fine- to medium-grained sandstone in lower part with basal conglomerate; fine-grained sandstone with mudstone intercalation in middle part; fine- to coarse-grained sandstone with conglomerate in upper; and the top is glauconitic shales. (Jain and Singh, 2019).
Lithology Pattern:
Sandstone
Relationships and Distribution
Lower contact
Unconformable onto Fincha Fm. [Rhaetian through Sinemurian is a hiatus.]
Upper contact
Gohatsion Fm, unconformably
Regional extent
Blue Nile Basin, Southeast Sudan and Northwest Ethiopia
GeoJSON
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Fossils
Age
?Pliensbachian – ?Bajocian
Age Span:
Beginning stage:
Pliensbachian
Fraction up in beginning stage:
0.00
Beginning date (Ma):
192.90
Ending stage:
Bajocian
Fraction up in the ending stage:
0.5
Ending date (Ma):
169.54
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.