Channel‐bend expansion and downstream translation, as well as vertical movements by aggradation and incision, set the stratigraphic architecture of channelized depositional systems. Early work on subm…
Understanding how environmental forcings (e.g., tectonics, climate) are transformed by erosional landscapes into sedimentary signals is a critical component of inverting the stratigraphic record. Prev…
The answer, at least for seven rivers of the Amazon Basin, seems to be negative, as we try to demonstrate in a paper that was recently published in Geology. My coauthors are Paul Durkin, at the University of Manitoba, and Jake Covault, at the Bureau of Economic Geology, The University of Texas at Austin. In this blog post, I try to provide a bit more background to our paper. Why is this an interesting result? After all, it makes sense that there is more outer bank erosion in sharper bends. Erosion is primarily a function of the shear stress exerted on the bank; and shear stress is high where the high-velocity core of the river gets close to the bank (because in this case flow velocity has to quickly decrease from a maximum to zero, and shear stress is a function of the rate of change in velocity). The high-velocity core gets pushed close to the bank if the centrifugal force is large; and the centrifugal force is directly proportional to curvature, 1/R (where R is the radius of curvature). In short, if we use the simplest, most pedestrian physical reasoning, we would expect that erosion, and therefore bank migration, are high in high-curvature bends. However, a lot of previous work on meandering rivers suggests that this is not the case. ...
One of the long- and widely held ideas about the dynamics of meandering rivers is that migration slows down in bends with higher curvatures. High-resolution measurements of migration rates of more tha…
Submarine fans in tectonically active continental-slope basins are targets of petroleum exploration and pro- duction. These slope fans commonly comprise compensationally stacked sandy and muddy archit…
Using a script that automatically calculates sinuosity and radius of curvature for multiple bends on sinuous channel centerlines, we have assembled a new data set that allows us to reevaluate the rela…