Zimam Fm
Period:
Cretaceous
Age Interval:
Santonian – Maastrichtian, Lb1
Province:
Libya
Type Locality and Naming
Lithology and Thickness
Members: 1. Had limestone, which is comprised of calcarenite to siliceous crystalline limestone, deposited in a shallow-water, low energy environment. 2. Upper Tar marl, which is hard, compact dolomites that represent an intertidal to supratidal depositional environment 3. Lower Tar marl.
Lithology Pattern:
Shallow-marine marl
Relationships and Distribution
Lower contact
Regionally, the schematic strat column indicates the next older unit as Mizdah Fm
Upper contact
Regionally, the schematic strat column indicates the next younger unit as Shurfa Fm
Regional extent
GeoJSON
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Fossils
Age
Santonian – Maastrichtian
Age Span:
Beginning stage:
Santonian
Fraction up in beginning stage:
0.5
Beginning date (Ma):
84.68
Ending stage:
Maastrichtian
Fraction up in the ending stage:
1.0
Ending date (Ma):
66.04
Depositional setting
Depositional pattern:
Additional Information
Compiler:
Chart derived from: USGS Correlation Chart and Columnar Section for Rocks in Libya, 1963. Descriptions from: Hallet, Don: Petroleum Geology of Libya, 2002.