The criterion for the transition between ripples and upper plane bed do hold for the observations from the data. Ripples and dunes occur when the shear stress is greater than the 3*Tcr and transitions to an upper plane bed when the Froude number occurs between 0.84 and 1. The graph shows that the upper plane bed points occur past the 3*Tcr limit and are mainly grouped between the boundaries of 0.84 and 1 Froude numbers. There are some examples of an upper plane bed occurring outside of these limits, with two occurring below 0.84 and one above 1. However, these Froude number boundaries represent generalities and do not set a strict limit that always results in the proper bedform given the conditions. Given what is seen, the other bedforms typically stay where they are expected, and the upper plane bed data points are mostly within the boundary.

For larger grain sizes, more energy is going to be required to move them. This means that with increases in grain size, the Tcr and calculated Utcr will be larger values. With larger Tcr and Utcr values, ripples and dunes will not start forming for larger grain sizes until there is a larger flow velocity. The boundaries of the Froude number will remain at 0.8 and 1 in order to differentiate between bedforms, but their positioning on the graph will also change as the flow velocity U increases. An increase in that value will increase the values generated to plot the lines for when the Froude number is 1 or 0.8. Overall, a similar dispersal of the bedform types should be seen as far the relative positioning of each group juxtaposed to the corresponding Froude numbers and other bedform types. What will be different than this graph is the scale of the axes.

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