Amb Fm
Type Locality and Naming
Zaluch Gr - lowest formation. Holotype section: 5.6 km SW of Amb village, Central Salt Range. Hypo: Chhidru & Zaluch nallahs, Western Salt Range. Saiyiduwali section, Khisor Range. Author: Teichert, 1966.
Lithology and Thickness
Sandy limestone. The formation consists mainly of brownish grey, medium to thick-bedded sandy limestone or calcareous sandstone. The sandstones are fine to medium grained with some occasional beds of greenish grey and light brown sandstone in the lower part. In the upper part, dark grey carbonaceous shales, limestone and occasional coal beds are present.
Reference section: In the KR reference sections the lower part of the formation is composed of dark colored shale containing thin bands of limestone; Hussain (1967) has named it Saiyiduwali member of the Amb Fm.
Thickness: 47-80 m. The formation is well developed in Western Salt Range and thins out both towards east and west. It is 80 m thick in type locality and 47 m in Khisor Range.
Relationships and Distribution
Lower contact
Disconformably underlain by Sardhai Fm
Upper contact
Conformably overlain by Wargal Limestone Fm
Regional extent
Exposures of the formation extend from Central Salt Range in the east to Khisor Range in the west.
GeoJSON
Fossils
The formation is richly fossiliferous and contains fossils from all the major phyla. It is rich in brachiopods and includes different species of Orthotichia, Cleiothyridina, Neochonetes, Derbyia, Spirifer etc. The fusulinids Monodiexodia kattaensis and Codonofusiella laxa indicate an early Permian (Late Artinskian) age.
Age
Depositional setting
Shallow to very shallow marine environment, with intermittent periods of paralic or lacustrine conditions during which carbonaceous shale and coal were deposited.
Additional Information