According to new research, without an explosion in ocean life more than 2 billion years ago, many of Earth’s mountains might not have formed.
When tiny organisms in the sea shallows, like plankton, die and sink to the bottom, they can add organic carbon to Earth’s crust, making it weaker and more pliable.
A case study of 20 mountain ranges around the world, including those in the Rockies, the Andes, Svalbard, central Europe, Japan and Indonesia, has now linked the timing of high carbon burial in the ocean with the very generation of our planet’s peaks.
“The additional carbon allowed easier deformation of the crust, in a manner that built mountain belts, and thereby plate margins characteristic of modern plate tectonics,” said the researchers.
The changes appear to have begun roughly 2 billion years ago, in the middle of the Paleoproterozoic Era, when biological carbon from plankton and bacteria began to add exceptionally high concentrations of graphite to the ocean floor’s shale. This made the rock brittle and more able to stack.
Within 100 million years, most mountain ranges began to develop in these weakened slices of crust.