Mount Everest, the world’s tallest peak, has long been known to grow slowly due to tectonic activity, but a recent study suggests it’s now growing at a faster rate than usual. According to research published in Nature Journal, this accelerated growth may be linked to a geological phenomenon called “river capture” or “river piracy” that occurred tens of thousands of years ago.
Accelerated growth of Mount Everest
While Everest typically grows by about 0.04 inches (1 millimeter) per year due to tectonic plate movements, recent GPS measurements reveal that the peak is now rising at about 0.08 inches (2 millimeters) annually. This may seem minor, but over time, this acceleration could significantly impact the peak’s towering height of 8,849 meters.
The role of ‘river capture’
Researchers from University College London have identified a river capture event as a possible factor behind the accelerated growth. Approximately 89,000 years ago, the Kosi River merged with its tributary, the Arun River, causing the rivers to change course. This event, known as river capture, led to enhanced erosion in surrounding regions, including the lower Himalayan peaks near Everest.
The river incision resulting from the capture event has eroded rocks near Everest’s base but has left the mountain itself relatively intact. This has allowed Everest to rise at a faster rate in response to the geological forces that typically cause the peak’s growth.
Geological insights
Scientists believe that this erosion has disproportionately affected nearby peaks, like K2, which stands at 8,611 meters, and others that are only slightly shorter than Everest. The new research highlights the “complex interplay between geological dynamics and topographic formation,” as Everest’s growth is not just driven by tectonic processes, but also by changes in river patterns that have occurred over millennia.
By using computer models, the researchers reconstructed the river capture process and showed how this event has likely accelerated the erosion of surrounding peaks while contributing to Everest’s continued rise.
Although tectonic activity remains the primary driver of Everest’s growth, this new research adds an intriguing layer of complexity to the mountain’s evolution. The study underscores how natural processes like river capture, in conjunction with tectonic dynamics, play a significant role in shaping the Earth’s most iconic geological features.
The discovery offers new insights into the forces that may allow Everest to grow even taller in the years to come.