 The Niger River flows, the Niger River drains a large part of Africa, bringing sediment into this area here, building out a delta. Waves from the Atlantic Ocean redistribute that sediment to make a wave-influenced delta. So let's take a closer look at this delta. And one of the characteristics of deltas generally is the flat delta plane. And in this zone here, you can see the multiple river channels joining and branching in an anastomizing pattern that makes up the delta plane. And the sediment from that delta is accumulated in a very large area here. It's a huge delta. So you can zoom in and to see some of the wave influences. You can see it a little bit in the roundedness of the coastline compared to river-dominated deltas. And you can also see it in the details of the channel. So for example, this channel is coming here and it gets diverted to the northwest by this spit of sand. And that the sand is being transported by waves in addition to the sediment that's coming from the river channel here. So if you zoom in a little more, you can see the effects of the waves on the sand transport. So you can see the crashing waves here. The beach is this very linear area and those waves are creating this sand spit. And these cloudy areas offshore are areas with significant suspended sediment from those breaking waves and it may also be a little bit shallower. So waves break when they start interacting with the bottom and the waves are breaking more here which suggests that there's an offshore bar in this area. One of the interesting things about this site is that you can see the waves are coming in at an angle to the coastline. What that means is that they're washing up on the shore and draining a little bit further north and it comes on and they're transporting sand back and forth to the northwest. And that's one of the things that actually builds up this bar and causes the deflection of the river to the north. So if we zoom back out a little bit, we can see how different the geometry of a wave influenced delta is than say the birds foot geometry of a river dominated delta. All the sediment that gets deposited at the mouth of the channel gets reworked by the waves into this rounded pattern with the beaches. And so in this particular case that the geometry of the delta is really quite different. And the sedimentary structures are also different because you have the development of those beaches on the edges. So let's go to a smaller wave influenced river. This is the Jetiquina Jona River off the coast of Brazil. And so we have South America here and there are a lot of waves again coming from the southern Atlantic but the other side that reworked sediment along the coastline. So this particular river is much smaller. So it's draining the interior of Brazil and coming down the meandering pattern and it only breaks into two rivers right near the mouth. There's a very distinct change in the landscape between this area here which has a densely channeled pattern and these very linear features here which represent old beach ridges. You can see that the delta has built out into the South Atlantic in this triangle form. But let's zoom in to some of those beach ridges and take a look at them. So again you can see the waves are crashing here and there'll be a berm along this area and there's enough water here to support quite a bit of vegetation. Then each one of these lines represents an old beach ridge that represents the berm from a former beach. Some areas it's lower and have ponded and there's a channel that's sort of draining this area and so this will be a lake area and it could either be fresh or salty water depending on how much water is flowing in from the land versus seeping through the sand from the ocean. But again this is a smaller delta but the wave influence is very distinctive in creating this linear shoreline with these beach ridges and that again is very distinctive and different from the river dominated deltas that have that bird's foot pattern. Thanks for watching.