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162meander scrolls, now abandoned, located along both banks of the Muri Ganga. These scrollsor bays have been subsequently infilled by sediment deposition and colonised by mangrove(the dark red colour in the satellite image: Figure13) A possible former meander pattern thatmight explain these abandoned meander scrolls is shown in Figure13. It is possible that thesetwo distinct meander patterns are caused by deposition in the Hugli estuary forcing thechannel in the Muri Ganga to avulse (i.e. switch from one pathway to another) possibly as aresponse to the alternate accretion and erosion of the estuarine bed surrounding the island ofGhoramara.Figure 13: Conjectural meander pathways in the Muriganga channel. The present situationis indicated by the thick black line. A possible former meander pathway is shown by thedotted line. Note that erosional areas are predicted at the outside of each meander bend(Pethick, 2008).156. Since the amplitude of a tidal meander is related to the tidal discharge and since thetidal discharge of the Muriganga is unlikely to change significantly, even allowing for sealevel rise, it may be proposed that the size of these meander scrolls and thus the erosionassociated with them, will not increase. Thus a finite erosional zone could be defined alongthe east coast of Sagar Island. It is equally apparent that the location of these erosion scrollsmay switch from place to place along the coast of Sagar Island depending on the pattern ofchange in the larger Hugli system.