Bandla Fm
Period:
Mesoproterozoic
Age Interval:
Early Calymmian
Province:
N.India Lesser Himalaya
Type Locality and Naming
Simla (Shali Basin), after Bandla Range. [Original Publication: Srikantia, S. V. and Sharma, R.P. 1976.Geology of the Shali Belt and adjoining areas. Memoirs Geological Survey of India, 106 (1), 31-166.]. Youngest unit of the Shali Gr.
Synonym: Madham Slates
Lithology and Thickness
Claystone. Shale, slate, siltstone, quartzarenite, green brecciated beds; 250 m
Lithology Pattern:
Claystone
Relationships and Distribution
Lower contact
Unconformable with Parnali Fm
Upper contact
It is youngest unit in the area – Bandla Range. Unconformable with DarlaVolcanics Fm
Regional extent
Shali Window and Bandla Range
GeoJSON
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Fossils
None
Age
(~1560 Ma). Age span from relative thicknesses of the 8 component formations to the 3300 m total span of the Shali Gr (see that entry for explanation)
Age Span:
Beginning stage:
Calymmian
Fraction up in beginning stage:
0.21
Beginning date (Ma):
1,558.00
Ending stage:
Calymmian
Fraction up in the ending stage:
0.23
Ending date (Ma):
1,554.00
Depositional setting
Not available
Depositional pattern:
Additional Information
Youngest unit of the Shali Gr, shows karstic facies in the basal and higher up in the sequence.
Compiler:
O.N. Bhargava & Birendra Singh. Age estimates based on A.J. Martin, 2017. A review of Himalayan stratigraphy, magmatism, and structure. Gondwana Research 49 (2017) 42–80.