Australia: The Land Where Time Began |
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MAPCIS - Massive Australian Precambrian-Cambrian Impact Structure
See also
The Massive Australian Precambrian-Cambrian
Impact Structure (MAPCIS) part one
The geological researcher Daniel Connelly has been accumulating evidence
in support of the presence of a very large impact structure that he
proposes was formed by the impact of an asteroid that was about 30 miles
in diameter in the centre of Australia, 300 km southwest of Alice
Springs in the Northern Territory, about 545 Ma. He suggests it is the
the largest impact site detected so far on Earth. He suggests it struck
with such force that it possibly changed the history of the Earth. He
presented his findings at the annual conference of the Geological
Society of America held in Portland, Oregon on October 19-21.
According to Connelly, the proximal ejecta from the impact led to the
formation of Ayer's Rock (Uluru), as enormous amounts
of crustal rocks were blasted into the atmosphere, with the generation
of large amounts of carbon dioxide that triggered a greenhouse effect
that is suggested by Connelly to have led to the
Cambrian Explosion.
Connelly has spent thousands of hours working on the project and is
convinced the proposed MAPCIS is valid, "I'm very interested in finding
allies willing to push the research forward, finance expeditions, drill
core samples into the impact melt sheet and verify this impact."
Among the evidence accumulated by Connelly are:
Pseudotachylite, a rare rock type created by intense friction, has
been found in arcing deposits up to 100 miles (about 161 km) long and
miles wide that ring the proposed impact zone to the southwest.
According to experts on impact craters, when pseudotachylite deposits
occur in such large amounts they are associated with impact craters.
Similar deposits, though on a smaller scale, are present at the
Vredefort Impact Crater in South Africa.
Radiating out in opposite directions from that of the impact blast zone
is an extensive web of ground faults that are believed to have formed as
a result of the impact forces as an asteroid plunged 25 miles (40 km)
into the crust.
In many places, in an almost worldwide distribution, a geological
"fingerprint" in the form of feldspar and zircon deposits dating to 545
Ma at the Precambrian/Cambrian Boundary has been found in such places as
a large swathe across North Africa, Israel and Jordan. In some places
the presence of these zircons has been seen as anomalous. In all cases
they have the same age of 1.12 Ga, as have the zircons of the
Musgrave Geological
Province
rocks, the proposed impact site of the asteroid, suggesting the impact
was the source of deposits of these minerals that appear to be out of
place at various sites in other parts of the world.
In a number of places, such as eastern Australia, Tasmania, New
Caledonia and New Zealand, as well as at the impact zone, unusual
concentrations have been found of osmiridium, a rare natural alloy of
osmium and iridium, all deposits of which are at the
Precambrian/Cambrian boundary. This pair of platinum group elements,
that are often present at the impact sites of asteroids, as occurs at
the Sudbury Crater in Ontario, Canada, where there is a large nickel
mine, suggests they are ejecta from the blast.
Connelly suggests the impact may have cracked and rotated the
continental crust along the Tasman Line, possibly initiating the
eventual separation and rifting away of Tasmania, New Zealand and New
Caledonia.
There are also a pair of proven impact craters hundreds of miles to the
northeast of MAPCIS, that are both of the same age as the MAPCIS, the
Foelsche Crater and the Kelly West Crater. They are strongly
suggested by Connelly to both be the result of chunks from the MAPCIS
that broke off the main body of the bolide a short time before impact,
and they are on the proposed flight path for the bolide.
He suggests the geologic age of all 3 impact sites were reset to the
same age of 545 Ma. He suggests the bolide approached from the northeast
at up to 70 km/s at a low angle, chunks dropping off as it neared the
impact site.
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Author: M.H.Monroe Email: admin@austhrutime.com Sources & Further reading |