The Whitecourt Impact crater is located in
a remote and heavily wooded forest about 20 km south of Whitecourt.
Local hunters for many years referred to
the site as a sinkhole. George VanderBurg, MLA for Whitecourt-Ste.Anne recalled
going hunting and using the site as a meeting spot. Wildlife could often be
found drinking the rainwater that had collected at the bottom of the basin.
Two brothers, Rod and Sonny Stevens, on
July 1, 2007 set out with metal detectors and found four fragments buried
adjacent to a circular hollow. They contacted the University of Alberta’s
department of earth and atmospheric sciences to confirm that the findings were
indeed meteorites.
The site is extremely rare as it one of a
dozen craters in the whole world that has associated meteorites. Experts
estimate that about 1100 years ago a meteor the size of a big tree trunk fell
to the earth creating the crater. The crater is 36 metres wide and nine meters
deep and has the appearance of a bowl. The second youngest crater in Canada is
located in Quebec and thought to be 1.2 million years old.
“The meteorites collected from the WMIC,
classified as type IIIAB iron, consist of almost entirely of jagged shrapnel.
The fragments collected outside the crater are slightly weathered and have no
fusion crust or regmaglypts. They are all of mm to cm scale with masses
typically in the tens of grams, the largest being 1.2kg”.[(source:40th
Lunar and Planetary Science Conference (2009) 1942.pdf]
The province of Alberta has designated the
site as a historic resource and is protected under the Alberta Historical
Resources Act. Signs clearly mark a zone
where it is illegal to collect or dig. Penalties include a $50,000 fine and/or
a year imprisonment. Outside this area
are public lands, where hunting is permitted and ANYONE OUTSIDE OF THIS ZONE IS
FREE TO TAKE/KEEP WHATEVER METEROITES THEY FIND. For purposes of scientific
research you are asked to fill out The Whitecourt Meteorite: report form http://eas.ualberta.ca/crater If you
happen to find a meteorite they want the GPS cords…so not only do we get to see
this amazing spot but as an earthcacher we can contribute to the ongoing
research.
Meteorite Identification Questions:
1. Does the specimen feel unusually heavy
for its size?
(Yes
= possible meteorite)
Many meteorites, particularly iron
meteorites, are quite dense and feel heavier than most rocks found on Earth.
2. Does the specimen attract a magnet?
(Yes = possible meteorite)
Almost all meteorites contain some
iron-nickel metal and attract a magnet easily.
3. Can you see gray metal specks shining on
any broken surface of the specimen?
(Yes = possible meteorite)
Most meteorites contain at least some
iron-nickel metal. These fragments may be seen shining on a chipped surface.
4. Does the specimen have a thin black
crust on its outer surface?
(Yes = possible meteorite)
When a meteor falls through the Earth’s
atmosphere, a very thin layer on the outer surface of the rock melts. This thin
layer is called a fusion crust. It is usually black and had the texture of an
eggshell.
5. Does the specimen appear to have
‘thumbprints or dents’ on its surface?
(Yes = possible meteorite)
Often, when a meteor falls though the
Earth’s atmosphere, these thumbprint-like features called regmaglypts form on
the surface.
6. Does the specimen have any holes or
bubbles in it?
(No = possible meteorite)
Meteorites do not have holes or bubbles.
Slag from industrial processes usually has holes or bubbles.
If the answers to questions 1 and 2 are No,
then the rock is almost certainly Not a meteorite. If the rock is actually a
meteorite, then the answers to most of questions 1 through 5 should be Yes, and
question 6 should be No.
To log this Earthcache please e-mail the answers to these questions:
Explore the perimeter and interior of the crater.
- What direction is the raised rim? Is it the highest point of the crater? Why/or why not?
2. Compare the vegetation inside the crater to the outside: i.e. types, size, and density. Does it indicate evidence of soil development?
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