Not sure exactly what kind of answer you're expecting... There's not enough to easily give a definitive location, however as I have a geology degree I can give some insight into the photo.
It looks like it's near the mouth of a river delta - one can see that the area of mud appears to narrow towards the top right of the photo and that there are water channels (heavily implied from small patch of bank at bottom of photo & pattern of channels etc), whilst in the bottom left one can see mud mixing with water showing the turbulence one would expect of a river delta heavy with sediment hitting a larger static body of water, eg a lake, or more likely the sea (as that volume of sediment on a constant basis would rapidly fill most lakes). The colouration & texture visible implies that it is likely to come from an area with fine sand / mud / clay sediments rich in iron oxide, so I'd guess the river passes through an area with some history of iron mining... but that's mostly just educated guesswork... so I'm perfectly happy to be corrected if anyone knows better...
It could potentially be somewhere in the South American rainforest (e.g. Amazon basin) as the soil there is iron rich and the rivers carry heavy sediment loads with this colouration.
