Antalo Fm
Period:
Jurassic, Cretaceous
Age Interval:
Callovian – Berriasian
Province:
Sudan E
Type Locality and Naming
Blue Nile Basin, Southeast Sudan and Northwest Ethiopia
Synonym: Antalo Limestone
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
600m thick, Succession of lower Marl (early Callovian); lower Limestone (mid-Callov through ?Oxfordian), upper Marl (early Kimm?) and upper Limestone (?mid-Kimm through Berriasian) (Jain et al., 2022 as shown on preprint by Mulugeta, 2025).
Lithology Pattern:
Limestone
Relationships and Distribution
Lower contact
Gohatsion Fm, conformably
Upper contact
Mugher Fm, ?conformable?
Regional extent
Blue Nile Basin, Southeast Sudan and Northwest Ethiopia
GeoJSON
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Fossils
Nannofossils (Nannoconus sp., N. compressus, Polycostella beckmannii and Watznaueria communis), Bivalves, Planolites, Thalassinoide, Chondrites, Brachiopods, Cephalopods (Orthosphinctes aff. tiziani, Paracenoceras cf. kumagunense, P. cf. ennianus, Purporoidea gigas, Pachceras cf. lalandenum, Paracenoceras cf. giganteum, Erymnoceras cf. coronatum), Benthic Foraminifers.
Age
Callovian – Berriasian (see Lithology description for more details)
Age Span:
Beginning stage:
Callovian
Fraction up in beginning stage:
0.00
Beginning date (Ma):
165.29
Ending stage:
Berriasian
Fraction up in the ending stage:
1.0
Ending date (Ma):
137.70
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.