What caused the Megaflood?
Likewise, people ask, how did the flood that formed the Scablands happen?
Large potholes were formed by swirling vortexes of water called kolks scouring and plucking out the bedrock. The Scablands are littered with large boulders called glacial erratics that rafted on glaciers and were deposited by the glacial outburst flooding.
Likewise, why did early settlers and explorers call this area the Scablands?
The early settlers in eastern Washington referred to these areas as scablands because they were not suitable for farming. During the last ice age 10,000 to 20,000 years ago, part of a glacier blocked the Clark Fork River in northern Idaho that normally flowed into Washington near what is now Spokane.
The floods swept across the Spokane Valley in eastern Washington, spilling into Glacial Lake Columbia. After overflowing the shores of Glacial Lake Columbia, the floods spread out across the landscape and tore a myriad of channels across much of eastern Washington, creating the Channeled Scablands.