Ghaylan Limestone Fm
Period:
Jurassic
Age Interval:
Hettangian – Callovian, Lb1
Province:
Libya
Type Locality and Naming
Column: Tripolitania And Sirte Basin
Synonym:
Lithology and Thickness
Layers of gypsum and anhydrite interbedded with limestone. Massive gypsum ad anhydrite with interbeds of dolomitic limestone and claystones and variegated shales.
Lithology Pattern:
Gypsum-Anhydrite
Relationships and Distribution
Lower contact
Regionally, the schematic strat column indicates the next older unit as Abu Shaybah Fm
Upper contact
Regionally, the schematic strat column indicates the next younger unit as B'ir Al Ghanam Gr
Regional extent
GeoJSON
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Fossils
Unfossiliferous.
Age
USGS chart places this anhydritic formation at the base of the Lias Stage, at the base of the lower Jurassic. Hettangian - Callovian
Age Span:
Beginning stage:
Hettangian
Fraction up in beginning stage:
0.0
Beginning date (Ma):
201.36
Ending stage:
Callovian
Fraction up in the ending stage:
1.0
Ending date (Ma):
161.53
Depositional setting
Deposited in an enclosed, evaporitic, subsiding basin
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.