International research led by geologists from Curtin University has found that a volcanic region in the Indian Ocean called the Kerguelen Plateau was the worlds most continuously active – erupting for 30 million years – fueled by a constantly moving conveyor belt of magma.
It is believed that this magma conveyor belt, created by shifts in the seabed, continuously made space available for the molten rock to flow for millions of years, beginning around 120 million years ago.
‘“Extremely large accumulations of volcanic rocks – known as large volcanic provinces – are very interesting to scientists due to their links with mass extinctions, rapid climatic disturbances and ore deposit formation,” explained the lead author Qiang Jiang.
“Twenty centimeters of lava a year may not sound like much but, over an area the size of Western Australia, that’s equivalent to filling up 184,000 Olympic-size swimming pools to the brim with lava every single year. Over the total eruptive duration, that’s equivalent to 5.5 trillion lava-filled swimming pools!
“This volume of activity continued for 30 million years, making the Kerguelen Plateau home to the longest continuously erupting supervolcanoes on Earth. The eruption rates then dropped drastically some 90 million years ago, for reasons that are not yet fully understood.
After the partial breakup of the supercontinent Gondwana, into the pieces now known as Australia, India and Antarctica, the Kerguelen Plateau began forming on top of a mushroom-shaped mantle upwelling, called a mantle plume, as well as along deep sea, mid-oceanic mantle ridges,” said co-researcher Dr. Hugo Olierook
“The volcanism lasted for so long because magmas caused by the mantle plume were continuously flowing out through the mid-oceanic ridges, which successively acted as a channel, or a ‘magma conveyor belt’ for more than 30 million years.
“Other volcanoes would stop erupting because, when temperatures cooled, the channels became clogged by ‘frozen’ magmas.
“For the Kerguelen Plateau, the mantle plume acts as a Bunsen burner that kept allowing the mantle to melt, resulting in an extraordinarily long period of eruption activity.”