"The folding accelerated 3 million years ago," Kapp said. "That's when the wind erosion turned on. I don't think it's a coincidence."
During the glacial periods, the winds whisked sediment out of the basin. As a result, the bedrock deformed faster because it was no longer weighed down by all the sediment.
Kapp calls the process "wind-enhanced tectonics." The term "tectonics" refers to forces that cause movements and deformation of the Earth's plates.
The whole process is driven by global climate change, he said. "The unifying theme is wind."
Kapp and his team are quantifying the processes further as they analyze more samples they brought back from the Qaidam basin and Loess Plateau.