About the Author:
Ron Brown is a geographer and heritage writer. He has authored more than twenty books, including
Rails Over the Mountains and
The Train Doesn’t Stop Here Anymore. A past chair of the Writers’ Union of Canada, he also conducts tours along Ontario’s back roads. He lives in Toronto, Ontario.
Ron Brown, a geographer and travel writer, has authored more than twenty books, including Canada’s World Wonders and The Train Doesn’t Stop Here Anymore. A past chair of the Writers’ Union of Canada and a current member of the East York Historical Society, he gives lectures and conducts tours along Ontario’s back roads. Ron lives in Toronto.
Ron Brown, a geographer and travel writer, has authored more than twenty books, including Canada’s World Wonders and The Train Doesn’t Stop Here Anymore. A past chair of the Writers’ Union of Canada and a current member of the East York Historical Society, he gives lectures and conducts tours along Ontario’s back roads. Ron lives in Toronto.
Excerpt. © Reprinted by permission. All rights reserved.:
CHAPTER TWO
THEY CAME FROM OUTER SPACE: THE CHARLEVOIX METEOR CRATER AND BIOSPHERE RESERVE
The Meteor
Every year tens of thousands of alien objects invade the earth’s atmosphere. They are not, however, living beings guiding their spaceships to invade our planet; rather, they are massive space rocks known as meteors and range in size from a few centimetres to hundreds of metres across.
Few make it to the earth’s surface, and those that do are called meteorites. In a few cases, they are large enough to explode and open up a crater in the earth’s surface. The result is known as an impact crater. The largest impact crater in the world, the two-billion-year- old Vredefort crater at three hundred kilometres across, lies in a field in South Africa, but Canada can count more than two dozen impact craters of its own. None, however, has had the earth-altering impact of the fifteen-kilometre-wide asteroid that blasted into the shallow seas off Mexico’s Yucatan Peninsula sixty-six million years ago, sending massive volumes of sulphur dust high into the atmosphere. The thick, poisonous cloud created a long, dark winter that wiped out the earth’s food supply, starving the dinosaurs into a mass extinction.
Not all impact craters can be easily identified from the ground, including the one that plummeted into the Yucatan. Most require an aerial vantage or geological survey. Their evidence, however, is sometimes plain to see. A few even boast historical plaques to celebrate their locations.
Canada’s largest meteor blew open the earth in today’s Sudbury region of Ontario. When the massive object smashed into the earth 1.8 billion years ago, its fiery collision created a crater that originally measured 150 kilometres across and altered the region’s chemistry enough to create an array of minerals, such as nickel and copper, that have made Sudbury the mining giant it is today. However, prolonged erosion and surface alteration has removed any visible crater formation, and only geological maps can reveal the shape and extent of the impact. Recent analyses have determined that the space intruder was, in fact, a comet and not the long-presumed asteroid.
One impact crater has become a major tourist attraction: the one near Flagstaff, Arizona, about two hours from the Grand Canyon. Exposed in a treeless desert, unobstructed by water or vegetation, it remains one of the world’s most clearly identifiable craters and likely one of the most visited. That explosive collision occurred a mere fifty thousand years ago and blasted open a circular depression that is 1,300 metres wide and 130 metres deep. The visitors’ centre contains a fragment of the fiery rock.
A popular hiking trail in eastern Algonquin Park leads to the small 3.8-kilometre-wide Brent crater, largely filled in with small lakes. Even smaller is the Holleford crater, little more than a ninety-metre-wide depression in a farm field north of Kingston. Yet, both are the subject of nearby historical plaques.
And then there is the Charlevoix impact crater. At fifty-four kilometres across, it is the eleventh-largest crater on earth and has been described as the eighth wonder of the world. When the two-kilometre-wide monster meteorite roared into the earth 340 million years ago, it totally reconfigured the geology of the region, exploding upward with a force thousands of times that of the American atomic bomb that destroyed Hiroshima. The core of the upthrust is the visible Mont des Éboulements.
The southern half of the crater lies beneath the waters of the St. Lawrence River, while the northern portion is defined by the rugged Laurentian Mountains. The interior ring surrounding the upthrust is relatively level and remains home to a rural population, making it the earth’s only inhabited impact crater. The outer ring consists of a higher ridge of largely Precambrian-era rocks.
The crater remained unknown until 1965, when Dr. Jehan Rondot studied a rock cut on the summit of Mont des Éboulements and saw the unusual shape of a shatter cone, literally a cone-shaped rock lined with clearly identifiable shatter lines.
The crater also has its own interpretation centre, the Observatoire de l’Astroblème, created by Professor Jean-Michel Gastonguay and located adjacent to the luxurious Fairmont Le Manoir Richelieu hotel at La Malbaie, Quebec. The building is actually the former golf clubhouse for the Manoir. Throughout the Charlevoix region, geological evidence of the huge explosion lies everywhere, from suevite beds (looking like grey lava flows) on the shores of the St. Lawrence River to fractures in limestone cliffs near La Malbaie.
From a distance, especially from the parking lot at the Observatoire, the level plain that surrounds the peak and the cone-shaped apex of the upthrust itself are all readily identifiable. Another fine view of the depression encircling the cone is that from Mont de la Croix at Saint-Hilarion.
Satellite imagery continues to reveal previously unknown craters in Canada, such as the twentyfive- kilometre-wide crater discovered on the Prince Albert Peninsula in the Arctic in 2012 and a buried crater in southern Alberta identified in 2014.
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