Najmah Fm
Period:
Jurassic
Age Interval:
Oxforidian – Kimmeridgian, Iq (2,3), Ir1, Kw1
Province:
Iraq, Iran, Kuwait
Type Locality and Naming
Columns: Central Iraq, Rutba Uplift (W Iraq), Zagros sedimentary basin (general), Kuwait; Upper formation in Riyadh Gr
Synonym:
Lithology and Thickness
Comprises from base to top: 1) Fine-grained recrystallized limestone with remnant shells and oolites, 2) oolitic limestone with macrofossil debris, 3) coarse granular dolomite with large zoned dolomite crystals and 4) thin anhydrites with fluffy limestone. 341m thick at type section
Lithology Pattern:
Dolomitic limestone
Relationships and Distribution
Lower contact
Regionally, the schematic strat column indicates the next older unit as Sargelu Fm with an unconformity (Kuwait, Central Iraq, Zagros sedimentary basin (general)). Muhaiwir Fm in Rutba Uplift (W Iraq).
Upper contact
Regional extent
GeoJSON
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Fossils
Age
Aalenian – Kimmeridgian (Oxfordian in the Central Iraq and Kuwait strat columns, Callov-Oxf in Rutba Uplift of W.Iraq). Generalized here to Oxfordian
Age Span:
Beginning stage:
Oxfordian
Fraction up in beginning stage:
0.0
Beginning date (Ma):
161.53
Ending stage:
Kimmeridgian
Fraction up in the ending stage:
0.0
Ending date (Ma):
154.78
Depositional setting
Depositional pattern:
Additional Information
Compiler:
From S. Z. Jassim and J. C. Goff, Geology of Iraq, 2006. pg 117, Fig. 10-1: "Stratigraphic correlation of Megasequence AP7."