homehome Home chatchat Notifications


Scientists find out waterfalls can carve themselves -- and this might rewrite geology books

Waterfall formation could be far more complex than scientists previously thought.

Tibi Puiu
March 14, 2019 @ 7:58 pm

share Share

Credit: Pixabay.

Credit: Pixabay.

Waterfalls can be breathtaking and awe-inspiring, but they’re not just a pretty sight — geologists study waterfalls to reconstruct the history of a landscape, and they do this based on one assumption: that they’re formed by an external force, like an ancient glacier or some fault line that deviated a river’s flow. But a surprising new study that suggests that waterfalls can from on their own might force some geologists to reconsider their previous investigations.

Water flows, water falls

The idea that waterfalls could spontaneously form without an external force has been proposed before. However, it was only recently substantiated by experiments. The researchers led by Joel Scheingross, an assistant professor of Geosciences at the University of Nevada, built a 26-foot long, 12-inch wide, 3.3-foot deep channel (8 meters long, 30 cm wide, 1 meter deep) that simulated a river flow. The channel was tilted at a 20-degree slope to allow sediment-rich water to naturally flow down its surface. Under the action of streaming water, a river bed will naturally start to erode — but this happens over the course of hundreds, even thousands of years. To fast-forward, the researchers designed their bedrock from foam.

To everyone’s surprise, the artificial river started digging out parts of the riverbed unevenly. Some pockets would erode faster than others, so in time the erosion amplified as the stream continued to flow. At some point, tiny waterfalls formed at various points of the channel, despite the fact that the sediment load, flow rate, or any other parameters suffered no change. These waterfalls appeared all by themselves with no external force involved — and this could apply on a grander scale, too.

“In our experiment, instabilities between flow hydraulics, sediment transport and bedrock erosion lead to undulating bedforms, which grow to become waterfalls. We propose that it is plausible that the origin of some waterfalls in natural systems can be attributed to this intrinsic formation process and we suggest that investigations to distinguish self-formed from externally forced waterfalls may help to improve the reconstruction of Earth history from landscapes,” the authors wrote in their study.

Real riverbeds are, of course, not made of foam — but the results are still compelling. Until now, everyone assumed that waterfalls were shaped by some natural force, whether tectonic movement, changes in sea level, or climate change. This assumption has been integral to efforts meant to reconstruct what a landscape might have looked like millions of years ago, like turning a sculpture back into a rough block of marble.

The new study suggests that the processes that can lead to the formation of a waterfall are more complex than scientists previously thought. But scientists will still have to confirm this experiment in the field by finding a self-formed waterfall.

The findings appeared in the journal Nature.

share Share

A Brain Implant Just Turned a Woman’s Thoughts Into Speech in Near Real Time

This tech restores speech in real time for people who can’t talk, using only brain signals.

Using screens in bed increases insomnia risk by 59% — but social media isn’t the worst offender

Forget blue light, the real reason screens disrupt sleep may be simpler than experts thought.

We Should Start Worrying About Space Piracy. Here's Why This Could be A Big Deal

“We are arguing that it’s already started," say experts.

An Experimental Drug Just Slashed Genetic Heart Risk by 94%

One in 10 people carry this genetic heart risk. There's never been a treatment — until now.

We’re Getting Very Close to a Birth Control Pill for Men

Scientists may have just cracked the code for male birth control.

A New Antibiotic Was Hiding in Backyard Dirt and It Might Save Millions

A new antibiotic works when others fail.

Researchers Wake Up Algae That Went Dormant Before the First Pyramids

Scientists have revived 7,000-year-old algae from Baltic Sea sediments, pushing the limits of resurrection ecology.

A Fossil So Strange Scientists Think It’s From a Completely New Form of Life

This towering mystery fossil baffled scientists for 180 Years and it just got weirder.

ChatGPT Seems To Be Shifting to the Right. What Does That Even Mean?

ChatGPT doesn't have any political agenda but some unknown factor is causing a subtle shift in its responses.

This Freshwater Fish Can Live Over 120 Years and Shows No Signs of Aging. But It Has a Problem

An ancient freshwater species may be quietly facing a silent collapse.