American Idyll

yes, the river knows

Tuesday, June 04, 2024

Roughly As Fast As Your Fingernails Grow


Debussy: Ballade




Earth processes that seem trivially slow in human time can accomplish stunning work in geologic time.
Let the Colorado River erode its bed
by 1/100th of an inch each year
(about the thickness of one of your fingernails.) Multiply it by six million years, and you’ve carved the Grand Canyon. Take the creeping pace of which the continents move (about two inches per year on average, or roughly as fast as your fingernails grow). Stretch that over thirty million years, and a continent will travel nearly 1,000 miles. Stretch that over a few billion years, and continents will have time to wander from the tropics to the poles and back, crunching together to assemble super-continents, break apart into new configurations- and do all of that again several times over. Deep time, it could be said, is Nature’s way of giving the Earth room for its history. The recognition of deep time might be geology’s paramount contribution to human knowledge.
--Keith Meldahl
Rough-Hewn Land


FOUR FROM HORSESHOE MESA
PUSH UP SOME MOUNTAINS

Powered by Blogger