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Wolfe Creek Crater is located on the edge of the Great Sandy Desert (152
kilometres South of Halls Creek) in the Wolfe Creek
Meteor Crater Reserve. The Crater is situated among low sand hills on a spinifex
grass plain and is a feature that stands out on the flat and almost featureless
landscape.
The crater is reputed to be the world's second largest confirmed meteorite
crater. (Some books state that it is the fourth largest meteorite crater.) It
has a diameter of 853 metres (another source says 880 metres) and is an almost perfect circle The bottom of the
crater is 46 metres below the level of the surrounding plain and about 60 metres
below the rim. The walls of the
crater are still sharp and complete. They have probably remained that way
because of the arid climate. The crater would originally have been about 120
metres deep but over time it has been slowly filled by wind blown sand and is
now less than half that depth.
1 - 2 million years ago (another source says 300,000 years ago) in the Pleistocene period a meteorite weighing
about 50,000 tonnes and travelling at 15 kilometres a second, came almost straight down from the north-east, penetrated the desert
floor and then exploded with the force of an A-bomb. Experts believe this
because of the even regular shape of the crater. If it had hit at an angle the
crater would be oval and the rim would be of uneven height. Large lumps of
weathered iron were found in the years after the crater was discovered. Some
weighed over 150 kilograms. Parts of the meteorite were found as much as 4
kilometres away from the impact site giving some indication of the force
generated by the strike.
The crater remained undiscovered or un-recognised as a
crater by Europeans until 1947, when it was noticed by an aerial survey. Even today it is only
visited during the dry season. It is accessible by a dirt road best suited to
four wheel drive vehicles. Perhaps the best way to see it is from the air but it
is a real experience to stand on the rim or even inside the crater. The
Aboriginal people of the area knew the crater existed and called it Kandimalal.
The European name Wolfe Creek was given first to the creek in
1889 and later to the crater in memory of a Halls Creek store keeper named
Robert Wolfe.
The area surrounding the crater was gazetted as a National park in August 1976.
The park covers an area of 1,460 hectares and is controlled by
CALM/DEC. Camping is
not permitted in the park itself but facilities are available at the nearby Carranya Station.
The road out to the crater is 4wd territory and the corrugations go on for a
long way. The best time to visit the area is just after the wet season when the
plants are green and the area is at its very best.
Probably the most frightening aspect of craters like Wolfe
Creek is the certainty that sooner or later a large impact such at the one that
occurred here will happen again somewhere on the surface of the Earth. It is
believed that catastrophic impacts may happen once every 15 million years but
smaller destructive impacts take place about every 50,000 years.
Scientists believe that at least 1000 asteroids with a
diameter of over a kilometre have orbits
that cross Earth's so it is only a matter of time before an impact like this
happens again. Luckily Earth is protected to some degree by the gas giants in
our solar system. They have very powerful gravitational fields that draw in many
objects that may otherwise collide with Earth.
Meteorites are valuable scientifically as they have changed
little since they were first formed. The Earth has undergone so many changes
that there is virtually no evidence left of its earliest form. Meteorites may
contain evidence of the origins of life on Earth as amino acids (one of the main
building blocks of life) have been found in them.
DEC Website for more
information
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