BengalAlluvium Fm
Period:
Quaternary
Age Interval:
Pleistocene to Holocene
Province:
NE.India West Bengal Basin, Bangladesh NW, Bangladesh SE
Type Locality and Naming
Type section is in the well Ranaghat – 1
Lithology and Thickness
Siliciclastics. Comprise of sand, gravel and clay.
[Figure 1: West Bengal Basin lithostratigraphy (after R.N. Dwivedi in Raju and Misra, 2009) with red-arrow showing position of this formation]
Lithology Pattern:
Clayey sandstone
Relationships and Distribution
Lower contact
This formation is unconformably overlies the Debagram Fm or Ranaghat Fm.
Upper contact
Present surface
Regional extent
Widespread fluvial-alluvial (and local soils on it)
GeoJSON
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Fossils
Age
Pleistocene to Holocene
Age Span:
Beginning stage:
Gelasian
Fraction up in beginning stage:
0.4
Beginning date (Ma):
2.27
Ending stage:
Holocene
Fraction up in the ending stage:
1.0
Ending date (Ma):
0.00
Depositional setting
Deltaic
[Figure: Environments of Deposition of West Bengal Basin (from dghindia.gov.in)]
Depositional pattern:
Additional Information
Compiler:
D.S.N Raju