With the picture above I posted being Ukraine's "Grand Canyon," I thought it was interesting that the Valley of the Headless in the Yukon, is also referred to Canada's "Grand Canyon."
China has approximately 10 "Grand Canyons" with one description that caught my attention.
The Yarlung Zangbo Grand Canyon area is the most mysterious region in
Qinghai-Tibet Plateau, because of its unique tectonic location,
scientists regard it as “keyhole that open the door of the earth's history”.Brahmaputra Grand Canyon (also named Yarlung Zangbo Grand Canyon), is the world’s deepest, longest, and highest (river valleys) canyon.
Though I'm not sure the one in China is in completely the northeast, I'll have to do more digging later today. Edit: I just remembered all of the weird stories coming out of Tibet however, so perhaps that may be part of the clue. See "Darkness Over Tibet"
Couldn't find a reference for a "Grand Canyon" in the Atacama, and while this likely isn't a specific signifier I did think it a little curious thing to take note of.