Lake Mead's water levels are low, researchers were able to locate volcanic ash that occurred 12 million years ago.
Due to Lake Mead's decreasing water level, several shocking things, including old warships, sunken boats, and human remains, have recently come to light. Now, scientists are announcing a brand-new find on the dry bed of Lake Mead: rocks covered in volcanic ash that fell on the southern parts of Nevada during violent eruptions about 12 million years ago.
Sedimentary rocks that haven't been seen since the 1930s, when Lake Mead was filled and the Hoover Dam was built, are being exposed by the record-low water levels. Researchers from the University of Nevada, Las Vegas, discovered ash deposits from volcanoes in Wyoming, Idaho, and California among these rocks.
Uncovered Sediment from 12 Million Years Ago
Co-author of the study and retired UNLV professor of geology Eugene Smith said they were surprised to discover so many of these ash units as Lake Mead's water level dropped.
Lake Mead levels have dropped to unheard-of lows as a result of the drought brought on by climate change in the West and excessive water use from the Colorado River. The lake's water level was only 1,045 feet above sea level in September or about 27% of its full capacity.
Due to the low levels, researchers can study previously submerged sediment that hasn't been visible for nearly a century.
Smith's research group discovered volcanic ash in previously submerged rocks that ranged in color from white to gray. To identify the ash's origin, they returned samples to their lab, but they discovered that it wasn't the result of a single eruption.
In places such as the Snake River Plain-Yellowstone region and eastern California, they discovered evidence of numerous volcanic explosions that occurred millions of years ago. The area is a chain of dormant volcanoes that stretches from Idaho through Yellowstone National Park and along the Snake River. Additionally, they discovered ash from recent eruptions, which, by geological standards, occurred no more than 32,000 years ago.
Jake Lowenstern, a research geologist from the US Geological Survey, said that analyzing past volcanic eruptions can help predict risk in the future. Lowenstern was not involved in the study.
According to Lowenstern, the most recent discovery in Lake Mead may be among the "better" collections of volcanic ash of the era. It will be crucial in helping us reconstruct the region's geologic history and comprehend the frequency of massive volcanic eruptions and their effects on the Southwest.
Read also: Ancient Ice in Antarctica and Greenland Reveals Massive Volcanic Eruptions from the Last Ice Age
Volcanic Ash
Even moderate volcanic eruptions can send ash hundreds of miles away, covering areas up to a few meters away with a heavy layer of material. Recent eruptions have demonstrated that the transmission of electricity can be disrupted by a few millimeters of damp ash. Additionally, the ash contains tiny, sharp grains that present a serious health risk when inhaled.
Smith said that these ashfall incidents have the potential to cause health risks, shut down airports, and interfere with supply and transportation networks. Local governments must create plans to handle this kind of incident, just as they have for seismic activity and flooding.
Smith said their most recent study may aid society in preparing for upcoming volcanic events, even those caused by distant volcanoes, as well as for current and projected climate change.
Smith also said that The secret to understanding the future is to study the past, and by studying previous volcanic eruptions, one can better understand how a future eruption might affect a significant urban area. Additionally, preparations can be made for volcanic eruptions in the future, CNN reports.
Related article: Corpses Found in Lake Mead have Turned 'Soapy' as Water Levels Become the Lowest Ever