Tawil Fm
Period:
Silurian
Age Interval:
Ludfordian – Pragian, Sa (1,2), Iq3
Province:
Saudi Arabia, Iraq
Type Locality and Naming
Column: Saudi Arabia Outcrop, Saudi Arabia Subsurface, Rutba Uplift (W Iraq). Contains Juraniyat Mbr, Tufayhah Mbr, Ghuwar Mbr, Samra Mbr
Synonym:
Lithology and Thickness
Black to dark brown weathering, massive, medium to coarse-grained quartz sandstone, in part with large-scale bedding. Locally red shaly intervals present in lower portions. Ironstone is developed as platy and concretionary masses at a number of horizons, particularly in the lower part. It is further divided into Juraniyat Mbr, Tufayhah Mbr, Ghuwar Mbr, Samra Mbr.
Lithology Pattern:
Coarse-grained sandstone
Relationships and Distribution
Lower contact
Regionally, the schematic strat column indicates the next older unit as Sharawra Fm. In Rutba Uplift (W Iraq), it is Alna Fm
Upper contact
Regional extent
GeoJSON
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Fossils
Age
Ludfordian – Pragian
Age Span:
Beginning stage:
Ludfordian
Fraction up in beginning stage:
0.65
Beginning date (Ma):
423.53
Ending stage:
Pragian
Fraction up in the ending stage:
0.5
Ending date (Ma):
411.46
Depositional setting
Depositional pattern:
Additional Information
Compiler:
From Middle East Geological Timescale 2008 Al-Husseini, Journal of Middle East Petroleum Geosciences v 13, no. 4