Trekkie Scientists "Boldly Go" and Discover New Secrets About Bedrock Rivers
A team of scientists recently decided to "go, like Star Trek, where no one has gone before," to uncover new truths about violent bedrock river flow. And their discoveries have not disappointed. According to a new study, rivers flow in a much more complex pattern than you could ever imagine.
The researchers, led by geologists from Simon Fraser University, decided to do something very uncharacteristic of their profession. Toting delicate and expensive oceanographic instruments, they decided to take an intense white water rafting trip down the Fraser River.
"For the first time, we used oceanographic instruments, commonly used to measure three-dimensional river flow velocity in low land rivers, to examine flow through steep bedrock canyons," Jeremy Venditti, a geologist and self-proclaimed Trekkie, explained in a recent statement. "The 3-D instruments capture downstream, cross-stream and vertical flow velocity."
According to the study, the researchers - not exactly practiced thrill-seekers - were guided through the violent canyon river by experienced rafters from Fraser River Rafting Expeditions. They visited 42 bedrock canyons in all, where the velocity and direction of the river's flow was measured. (Scroll to read on...)
What they found surprisingly goes against standard train-of-thought. When we see a river tearing its way through a canyon, we assume that all the water is rushing in one direction. However, this doesn't seem to be the case.
"We observed a complicated flow field in which high velocity flow plunges down the bottom of the canyon forming a velocity inversion and then rises along the canyon walls," said Colin Rennie, an Ottawa University researcher who took part in the expedition. "This has important implications for canyon erosion because the plunging flow patterns result in greater flow force applied to the bed."
The researchers add that better understanding river flow patterns can help them learn how erosion will cause sediment to deposit, and how natural formations arise.
The full results of the study were published in the journal Nature on Sept. 24.
Researchers have also similarly been looking at wind erosion, learning what forces help form the phenomenal sandstone arches we can find in regions like Utah, home of the world-famous Delicate Arch.