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Dakota Datebook
October 10, 2003
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Yesterday, we talked about a five-foot meteorite that
landed near Carrington in 1910. But about 214 million years ago, a meteorite
that landed in what is now McKenzie County was so large that it left a
crater 5 miles across.
Many people confuse meteors with shooting stars. Generally,
a shooting star is the size of a grain of sand. A meteor, on the other
hand, is large enough to survive its fiery trip through the atmosphere
to reach the earth's surface at which point it becomes a meteorite.
Meteors of this size are often asteroids or comets or fragments from a
comets tail.
The Red Wing Creek crater near Williston is believed by many scientists
to be connected to a group of at least five massive comet fragments that
bombarded the earth within hours of each other during the Triassic Period
about 240 millions years ago.
The largest crater formed by these collisions
the Manicouagan in Quebec is 62 miles across. The remaining three
of the group are in Manitoba, France and the Ukraine. The craters are
located very far apart from each other, but at the time of impact, the
planets continents were still primarily one land mass, and the five
locations were very close together.
When large meteors like these collide with the earth,
the damage can be spectacular. Shock waves roll over the earths
surface, through its fragile crust and into its mantel & core. Trillions
of tons of debris can be sent into the atmosphere.
Dust and debris from cosmic collisions and explosions
can remain in the atmosphere for months and sometimes even years. Around
the year 535 AD, Earth was wrapped in a swarm of atmospheric debris that
produced two years of continuous winter. Its believed that this
vast dust cloud came from either outer space or from a massive volcanic
eruption somewhere on the globe.
During those two years, it snowed in the winter, drought-stricken
areas had constant flooding, crops failed, and famine decimated Italy,
China and the Middle East. A 6th-century Syrian bishop wrote, "The
sun became dark... Each day it shone for about four hours and still this
light was only a feeble shadow." This event marked the beginning
of... the Dark Ages.
When the Red Wing Creek grouping landed, the impact of
comet fragments was nothing short of catastrophic. In fact, its
believed that these collisions caused historys 3rd largest mass
extinction, affecting approximately 80% of the planets species and
bringing the Triassic Period to a close.
Many millions of years later, a massive meteor hit Mexico,
forming a crater more than 100 miles across. This one is believed to have
caused the mass extinction of the dinosaurs at the end of the Cretaceous
Period.
Despite the fact that North Dakotas Red Wing Crater
is more than five miles across, it unfortunately has filled in over the
millennia and cant be seen from either land or air. Unlike craters
formed by volcanoes that leave a rim above ground level, the Red Wing
Crater, as well as another smaller on in Renville County called the Newporte,
are both below ground and were accidental discoveries recently made by
oil drillers.
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