According to new research, an underground magma ‘conveyor’, which pushes against the Earth’s surface for millions of years, has been the cause of the longest duration of super-volcanic eruptions ever seen on the planet, according to a new study.
The change in the seabed caused channels to form, through which magma can flow freely, the researchers said. This resulted in an eruption period that lasted from about 122 million years ago to 90 million years ago; in particular, consider that normally these flows only last 1-5 million years.
It all took place on the Kerguelen Plateau, currently located under the Indian Ocean. It is called a great fire province or LIP, a large accumulation of magma and lava. Scientists can use these LIPs to track volcanic activity over time.
Geologist Qiang Jiang, from Curtin University in Australia, said: “The massive accumulation of volcanic rock ̵1; known as large volcanic provinces – is very interesting to scientists due to the connection of them with mass extinction, rapid climate disturbance and sediment formation ”.
Jiang and his colleagues used black basalt samples taken from the seabed, along with the argon isotope dating method to determine the spread and emergence of LIP when it was on top of called mulch, created by rising magma.
During more than 30 million years of intense activity, the Kerguelen Plateau has grown by about 20 centimeters (7.87 inches) per year, the researchers report. Across the entire LIP’s colossal size – about three times the size of Japan – the ejection equivalent of lava fills 184,000 Olympic-sized pools each year.
The Kerguelen Plateau witnessed such a long and stable sequence of supercano activity due to its unique configuration, research showed: a bundle of feathers combined with spreading mid-ocean ridges slowly conduits magma on top.
“Volcanoes last too long due to the mantle’s magma constantly flowing through the mid-ocean ridges, constantly acting as a channel, or a clearer ‘magma conveyor,'” said geologist Hugo. 30 million years “. Olierook, from Curtin University.
“Other volcanoes will stop erupting because as the temperature cools, these channels are clogged with ‘freezing’ magma. For the Kerguelen Plateau, the mantle acts as a continuous Bunsen burner allowing the layer to be The coating melts, resulting in a special long time eruption activity. “
That was a lot of volcanic eruption over the millions of years, but the rate dropped dramatically around 90 million years ago, and scientists are still not sure why. Related volcanic activity continues to this day, on a much smaller scale.
It’s a fascinating look at our planet’s past history, and of course it informs our research on volcanic activity today – the more we know about how these types of systems are. This system can be formed and kept active, the better we can understand the interactions taking place under the Earth’s surface right now.
“Finding this persistent, persistent eruption is very important because it helps us understand what factors control the initiation and the end of the eruption,” said geologist Fred Jourdan from Curtin University. the end of volcanic activity ”.
“This has implications for how we understand magma on Earth and on other planets.”
Research has been published in Geology.