LAKE POWELL, Utah (ABC4) – As the current drought forces Lake Powell to recede, geologists are eager to examine the now exposed sediments.
By looking at the layers, geoscientists can better understand Lake Powell. Layers of sandstone might suggest shallow water or beach sites. Mudstone could suggest deeper water formed around the area. Layers of these alternating stones could suggest a shoreline that advanced and retreated rapidly and frequently.
“It’s knowing what the rivers were doing with monitoring data, what the reservoir was doing with spatial data, satellite data and topographic data,” United States Geological Survey (USGS) scientist Casey Root says. “You have a good idea how the rivers and landscape have changed over the lifespan of Lake Powell.”
Most sediments at Lake Powell show layers of sandstone and mudstone because of the constantly changing shoreline. One section of sediments shows a meter and half tall section of sand. This event was likely the wet year of 1983 that caused flooding in Salt Lake City. Such a large runoff brought in a large amount of sand.
By looking at Lake Powell’s past we can better understand its future.
“Two-thirds of the land area that used to be a lake is now a terrestrial ecosystem full of tamarisk, Russian thistle, cheatgrass and fine-grained sediment that was never there before,” USGS scientist Scott Hynek says. “It’s a completely new ecosystem emerging out of this area that used to be a lake.”
The full study can be seen here.