The world beneath our feet is replete with new rock structures created by the many nuclear tests and drilling that will remain for millions of years as man’s most enduring legacy, a new study by geologists says.
It is a world that is usually out of sight and out of mind, but humans have left many kinds of mark on the planet, and some of the most remarkable and enduring are in the subterranean ‘underworld’ of rocks, hidden deep below our feet.
Humans have created true geological novelties, according to experts Jan Zalasiewicz and Mark Williams of the University of Leicester, and Colin Waters of the British Geological Survey in a new paper published in the academic journal Anthropocene.
Among the observable novelties are the effects of human drilling on the geological ‘underworld’.
Zalasiewicz said, “Human drilling into the Earth’s crust to extract minerals or store wastes may be regarded as ‘anthroturbation’, comparable to the burrows made by worms and other animals but on a vastly greater scale.
“Anthroturbation has created textures and structures underground that are unique within the animal world. No other organism has made igneous and metamorphic rocks — and yet we have made many tons of these in underground nuclear tests, in shock-fracturing and by melting the rock around the blast.” Anthroturbation commonly extends to several kilometres in depth, as compared to the few centimetres or metres that non-human organisms achieve.
Examining the effects of human drilling shows how humans have left their mark on the Earth both above the surface and deep below. Professor Williams added, “Many of these underground transformations, being beyond the reach of surface erosion, will effectively last forever. They can be preserved for millions and even billions of years into the future, and thus may form our most enduring — and most puzzling — legacy, for any intelligent creatures that may inherit the Earth from us.”