Magma Deposit under New Zealand Town

Magma deposit eruption

New Zealand is sadly renown for its volcanic activity.

A team of scientists discovered a new magma deposit 120 miles away from Auckland, New Zealand. This newly found chamber can also be responsible for the chain of earthquakes that affected the small city of Matata in the last years.

The chamber is estimated to have a size of 80,000 Olympic swimming pools. Even though geophysicists say there is no danger coming from the underground, there still are increments of magma that go into the crust and that can reach out to the surface.

The scientists discovered the deposit by using radar data gathered by various satellites. In a first study, they measured horizontal and vertical changes and ground motions around the Taupo Volcanic Zone.

Taupo was a massive volcano that started to be active 300,000 years ago, and since then it had erupted periodically every thousand years. These series of explosions left a significant impact on the surrounding landscape. Up until now, the volcano gathered 25 massive eruptions.

Researchers have found that the Taupo zone started to sink, which is explained by magma redrawing into Earth’s core.

While researching Taupo, scientists also found modifications in the western part of the islands. At that time they ignored them, but later the study continued as such ground differences were obviously an anomaly in that specific area.

“There is every possibility the magma body under the Bay of Plenty Coast had been there for centuries, and possibly even longer,” said Ian Hamling, leading author of the study.

The study involved data that was gathered for the last 50 years and it follows the modifications in ground elevation.

The historical analysis of radar images showed that in the beginning, Matata rose 5 millimeters each year, and then accelerated to 12 millimeters per year in the mid-2000s. In the more recent years, the elevation continued at a lower rate.

This finding may explain the numerous small earthquakes that shook the area between 2004 and 2011. Initially it was thought that the abrupt ground movements were caused by tectonic shifts, but now geologists believe they might have also been created by magma stress.

The volcano under the city of Matata may rise after a couple of hundreds or thousands of years. Another likely scenario is that the magma would eventually cool off.

New Zealand is the home for many active volcanoes that occasioned extreme disasters. The 2011 Christchurch earthquake provoked no less than 185 dead.

Image Source: PD4Pic