Lake Taupo is located in the center of New Zealand’s North Island. While its surface appears calm and peaceful, it hides a supervolcano that is still active. The volcano is still rumbling and causing nearby soils to shift, scientists say.
The surrounding landscape has completely changed
The waters of Lake Taupo lie within a prehistoric caldera (cauldron, in Spanish), a giant, round volcanic crater. It was formed 25,400 years ago after the volcanic eruption of Oruanui. When the magma was released to the surface, the surrounding landscape changed completely.
The supervolcano has been active 25 times in the past 12,000 years, according to the authors of this new study, published in the New Zealand Journal of Geology and Geophysics. The most recent activity dates back to 232. Scientists note that this is one of the most explosive eruptions that have occurred on our planet in historical times. After this event, at least four documented episodes of unrest occurred on the volcano. These bouts of unrest led to terrible earthquakes and massive subsidence in 1922.
Several episodes of geological disturbances over the past 35 years
In this new study, the researchers analyzed data collected over 42 years from sounding stations placed at about 20 locations around the lake. Finn Illsley-Kemp, lead author of the study, explains that since the new survey methodology was introduced in 1979, four surveys have been conducted each year.
So far, scientists have observed seven episodes of geological unrest in Lake Taupo. The latter noted ground shifts as early as 1983. They note that during episodes of geological unrest, the northeastern end of the lake tended to rise, the lake bed near the center of the fault belt sank, and the southern end sank slightly.
This study shows that the volcano under the lake is still active. Scientists note, however, that there are no signs that it will erupt soon.