By Susan Hickman
Carleton geologist Richard Ernst’s work on reconstructing ancient continents – linking geological belts at opposite ends of the Earth that might hold valuable mineral and ore deposits – has been published in the April 11 online issue of the prestigious Nature Geoscience journal.
Ernst, co-leader and co-ordinator of the LIPs-Supercontinent Reconstruction Project and scientist-in-residence at Carleton’s Earth Sciences Department, has been working with a consortium of geologists for six years to better understand the record of large igneous provinces (LIPs) – powerful volcanic events that break apart continents and transform the Earth’s climate – and what they tell us about how various regions of the world were once linked.
Their findings have been published in an article called “Long-lived connection between southern Siberia and northern Laurentia in the Proterozoic.”
The project was funded by six companies, as well as the Natural Sciences and Engineering Research Council (NSERC).
“These companies are interested in the research we are doing on supercontinent arrangement in the past because it can identify a continuation of metal rich ore deposits that were beside each other millions or billions of years ago when they formed.”
Ernst plans another trip to Mirny, Siberia to discuss the importance of these great historic volcanic events for diamond exploration with Russia’s large diamond mining company ALROSA.
Determining the parts of today’s continents that once were adjacent by dating LIP rock samples has major implications for mining and hydrocarbon exploration. Once the project research team files a report on its findings, funding companies have a year to keep the information confidential and thus use it to competitive advantage.
“We have done a lot of dating in Siberia, particularly in the south, which has given us a dramatically improved understanding of the LIP record there. And we can compare that with the better known LIP record in Laurentia, in northern Canada,” says Ernst. “Southern Siberia, near Lake Baikal, must have been attached to northern Laurentia for a billion years.”
The topic of LIPs, a relatively new concept in Earth Sciences that originated in the early 1990s, is Ernst’s passion. His extensive resource book, Large Igneous Provinces, was published by Cambridge University Press in 2014.
LIPs occur every 20 to 30 million years over a short span of geological time, discharging more than 100,000 cubic kilometres of magma, or liquid rock, generated via a hot upwelling from thousands of kilometres deep within the Earth, which can cover an area the size of Canada to a depth of 100 metres.
“The largest is possibly 70 million kilometres of rock, which would cover the entirety of Canada to seven kilometres thick,” Ernst explains.
These LIPs have a credible link, he adds, with large deposits of nickel, copper and platinum group elements. They are also linked to global extinction events, such as the disappearance of dinosaurs, and to major climactic change.
The key research results will become a building block for continuity of geological belts between northern Laurentia and southern Siberia.
“Our next step is to integrate the geology of the two blocks at all levels, and determine their history through more than a billion years of time.”
He hopes to do more dating in Siberia and to look for a link between Victoria Island in the Canadian Arctic Archipelago, for example, and the southern Siberia region around Irkutsk to see if there is ore deposit potential for nickel, copper and platinum group elements.
“LIPs,” says Ernst, “are my baby, and I want to understand everything about them through space and time on Earth and on other large planetary bodies, such as Venus and Mars.”