This paper documents the bankline dynamics of the Brahmaputra River
along the India and Bangladesh region during the period 1976 to 2018.
Multiple approaches, including satellite image-based interpretations,
fieldwork, and meta-analysis, are performed to explore the factors
responsible for the morphological dynamics of the river. Results suggest
that the Brahmaputra River has lost ~2686 sq. km of land
in the last four decades. Brahmaputra river has also widened
~1.7 km (mean value over the studied reach) during the
period. We identified five active erosional sections along the river.
The high erosions along these sections are promoted by the past avulsion
and the lowlands areas in the floodplain of Brahmaputra. Interestingly,
progressive erosions along the active sections of the Brahmaputra River
have been sustained for decades to centuries. Sustained and dominant
peripheral second order channels (dominant channels) have largely
decided such progressive erosions. Interpretation based on historical
maps suggests that the observed morphological changes of the Brahmaputra
River are the continuation of the river’s recent planform evolution that
can be traced back to 2-3 centuries. These rapid morphological changes
in Brahmaputra River are conceivably due to high sediment flux, where
seismic activities look to be a pragmatic factor.