Aut Fm
Period:
Mesoproterozoic
Age Interval:
1480-1460 Ma; middle Calymmian
Province:
N.India Lesser Himalaya
Type Locality and Naming
Himachal Pradesh-Uttarakhand, Deoban Basin, named after Aut Village. [Original Publication: Sharma, V.P. (1977). Geology of the Kulu-Rampur Belt, Himachal Pradesh. Mem. Geol. Surv. India, In: Stratigraphy and Structure of parts of Simla Himalaya., Mem. Geol. Surv. India, 106, 235-407.]
[Figure: Geological map of Larji Gr (Aut Fm and Hurla Fm) (provided by O.N. Bhargava & Birendra Singh)]
Lithology Pattern:
Dolomitic limestone
Relationships and Distribution
Lower contact
Conformable with Hurla Fm
Upper contact
Unconformity and no deposition in the Larji Window.
Regional extent
Exclusively within the Larji Window.
GeoJSON
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Fossils
Unfossiliferous; Stromatolites: Conophyton, Colonella and Tungussia
Age
1480-1460 Ma. Age span estimates partly taken from Miller, C., Klötzli, U., Frank, W., Thoni, M., Grasemann, B. 2000. Proterozoic crustal evolution in the N.W. Himalaya (India) as recorded by circa 1.80 Ga mafic and 1.84 Ga granitic magmatism. Precambrian Research, 103, 191-206.
Age Span:
Beginning stage:
Calymmian
Fraction up in beginning stage:
0.6
Beginning date (Ma):
1,480.00
Ending stage:
Calymmian
Fraction up in the ending stage:
0.7
Ending date (Ma):
1,460.00
Depositional setting
Shallow marine, supra-tidal.
Depositional pattern:
Compiler:
O.N. Bhargava & Birendra Singh.