An "ancient Jurassic world" comprising around 100 volcanoes has been found buried deep inside central Australia. The "fiery region" has been named Warnie after legendary Australian cricketer Shane Warne.
The volcanoes developed in the Jurassic period, between 180 and 160 million years ago, and were buried beneath hundreds of meters of sedimentary rocks in the Cooper-Eromanga Basin, Australia’s largest onshore oil and gas producing region.
“But, despite about 60 years of petroleum exploration and production, this ancient Jurassic volcanic underground landscape has gone largely unnoticed,” an international team of subsurface explorers from the University of Adelaide in Australia and the University of Aberdeen in Scotland said in a statement.
The researchers used advanced subsurface imaging techniques, similar to CT Scans, to identify the “plethora of volcanic craters and lava flows, and the deeper magma chambers that fed them.”
Their findings have been published in the in the journal Gondwana Research.
During the “Jurassic times,” the researchers say, the now dry and barren landscape of the Cooper-Eromanga Basins would have been a landscape of craters and fissures, “spewing hot ash and lava into the air, and surrounded by networks of river channels, evolving into large lakes and coal-swamps.”
“While the majority of Earth’s volcanic activity occurs at the boundaries of tectonic plates, or under the Earth’s oceans, this ancient Jurassic world developed deep within the interior of the Australian continent,” co-author Associate Professor Simon Holford, from the University of Adelaide’s Australian School of Petroleum, was quoted as saying.
“Its discovery raises the prospect that more undiscovered volcanic worlds reside beneath the poorly explored surface of Australia.”
The researchers said the latest discovery suggests a lot more volcanic activity in the Jurassic period than previously supposed.
“The Cooper-Eromanga Basins have been substantially explored since the first gas discovery in 1963,” says co-author Associate Professor Nick Schofield, from the University of Aberdeen’s Department of Geology and Petroleum Geology.
“This has led to a massive amount of available data from underneath the ground but, despite this, the volcanics have never been properly understood in this region until now. It changes how we understand processes that have operated in Earth’s past.”
The research was carried out by Jonathon Hardman, then a PhD student at the University of Aberdeen, as part of the Natural Environment Research Council Centre for Doctoral Training in Oil and Gas.
The researchers named their discovery the Warnie Volcanic Province after one of the drill holes that penetrated Jurassic volcanic rocks (Warnie East-1) and in recognition of legendary Australian cricketer Shane Warne.
“We wrote much of the paper during a visit to Adelaide by the Aberdeen researchers, when a fair chunk was discussed and written at Adelaide Oval during an England vs Cricket Australia XI match in November 2017. Inspired by the cricket, we thought Warnie a good name for this once fiery region,” Holford said.
The discovery raises "the possibility of other, yet unidentified, volcanic provinces worldwide," according to the study.
Last year, scientists had found a chain of ‘seamounts’, or undersea mountains, while mapping the seafloor 247 miles off the coast of Tasmania.