London Canyonlands

In a recent post I compared the fissured earth of Morocco's Atlas Mountains to the Grand Canyon.


Whether or not such a comparison holds – and I've received several opinionated emails either side – it's still interesting to speculate about the "peculiar geological circumstances surrounding the Grand Canyon" and whether they might be found elsewhere – even if that's a few hundred million years from now.
As it happens, I'm reading Richard Fortey's fantastic new book Earth, and lo! He's been thinking what I'm thinking:
"If we could wave a tectonic magic wand," he writes, "and gently elevate southern England, the River Thames would excavate a canyon of its own, another magnificent thing – and, deep enough, there would be the equivalent of the [Grand Canyon's] Vishnu schist. If we do the same in northern France, the Seine would carve through a sequence of hard and soft layers back to a deep and ancient metamorphic foundation. The same goes for Texas, or the Pirana Basin, or the Arabian Peninsula, or western Africa, or much of Siberia."
There are Grand Canyons everywhere, in other words, waiting for the right conditions in which to form.


The question, then, is what can be done to further this process? Could we "gently elevate southern England," as Fortey says, perhaps learning from the project to lift Venice?
Could we prop-up Texas on some oil derricks, for instance, moving those platforms further and deeper underneath the continental plate every year till the whole thing is an artificial Himalaya – then let the Rio Grande carve away?
For that matter, could you perform an exact, laser-measured study of the internal volume of the Grand Canyon – then carve another one, in western China, or right in the heart of Greater London?
Open a chain of hotels nearby, and you'd make all your money back through tourism. And geologists would love you. The world's first university-sponsored Grand Canyon. Harvard will buy it.
Fortey himself compares the Grand Canyon to an act of carpentry: "The strata appear unwaveringly horizontal, like an infinity of stacked plywood worked with a giant fretsaw."
So what are our geotechnical options here?
How could we realize a world full of new Grand Canyons?

(Earlier: sandblasting Manhattan into a new Arches National Park).