 Okay, so we've been talking about sediment transport in terms of the flow characteristics and the boundary layer, the base of flows, and the Bernoulli effect, which less grains off the bottom, and the difference between bed load and suspended load transport. So now we're going to get a little bit more quantitative by using this Holstrom diagram. So it plots grain size along the x-axis and flow velocity, which is u in our Reynolds number equation, on the vertical axis. And both of these are log scale, so you have a one millimeter grains here, the next line represents 2, 3, 4 on up to 10, and the same thing along the flow velocity axis here. And what this diagram shows is the flow speeds at which different grains are transported or deposited, plus the way that they are transported. So the way you read this diagram is we'll start at grain size of one millimeter. And if the flow speed is 0.1 centimeters per second, it's in this deposition zone here, that means it's not actually going to be transported. If the flow speed increases up to this point here, you start getting a transport of that grain. It becomes possible. So that transport is possible at 4, 5, almost 6 centimeters per second. So we look at this spot here. We can basically read this line as at 6 centimeter per second flow, a one millimeter grain might move. I say might because it does depend on the characteristics of the bed and how far it's sticking up into the flow. As the flow speed gets even faster, it's more and more likely to be transported as bed load. And so in the zone all the way from here up to this next line, it's moving along the bed as a combination of saltating and rolling grains. By the time you get to here, you get to the erosion zone. And that looks like it's about 10, 20, 30, 40, at about 40 centimeters per second. We're getting into the speed where it mostly erodes. So at 40 centimeters per second, one millimeter grains are usually eroded. And the difference is that at this bottom end, the grains might move a little bit. But as you go faster and faster, the flow gets faster and faster, and the boundary layer shear gets greater and greater, the grains are more likely to be lifted by the Brunnerly effect and washed downstream. And that means that you often do not get those grains deposited and they wouldn't be left in the rock record. So we can look at it a different way, and I will choose this orange color here. We can look at it in terms of a specific flow speed. So let's choose a flow speed of 10 here, and we can ask which grain sizes will actually be transported by that flow speed. So if we trace this along here, we get all the way over to this grain size, which is about two millimeter size grains. So everything that's smaller than that size, it can actually be moved by a flow that's at 10 centimeters per second.