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Some people will be bleating at the top of their voice -"HAARP!"
Freak
anomaly: Low-seismic Alaska area shaken by mysterious series of
quakes
A
swarm of identical earthquakes has hit Alaska – taking place in the
same low-seismicity area in the northwest, all at the same 5.7
magnitude. The fifth and latest event took place on Monday, leaving
scientists puzzled
17
June, 2014
The
eerily similar tremors, which have been taking place regularly since
April 18, woke people up at around 4 am. No one in the Inuit Eskimo
community in Noatak is used to earthquakes - there are no major
active fault lines and the latest such incident took place back in
1981.
The
area is about 100km north of the Arctic Circle. The April swarm
struck about 30km from Noatak at a depth of about 16km. Just as with
previous temblors, there were no injuries, apart from minor
structural cracks in Noatak.
The
latest tremor epicenter was located northeast of the village, the
Alaska Earthquake Center reported.
Herbert
Walton told the Arctic Sounder that “the
whole house shook… we’re concerned.”
While
many slept through the quake, locals still fear “there’s
going to be a bigger one, because every time it happens, they seem to
be getting bigger,”
Walton said.
The
regularity is a little bit offset. While the first two events
happened in rapid succession on April 18, the third event did not
happen until May 3. But all four were about the same magnitude, which
is part of the reason the events are being treated as a group and
called a “swarm”
by Mike West, with the Earthquake Center.
Each
event has since been accompanied by 300 smaller aftershocks, their
magnitude reaching 3 at times. A 4.2 foreshock was also present this
time, just before the main event hit. It was then followed by no less
than 10 aftershocks.
)
What
is worrying to West is that the aftershocks are “unusually
vigorous”
and that the temblors “all
have the same cause; the same fault motion”
and “occur in more or less
the same place.”
What is strange here is that unlike other strong aftershocks, these
ones do not have a tendency to reduce in magnitude – they pulse in
the same way.
Scientists
so far have no answers as to what could have caused this. Ruppert
thinks that tremors don’t happen unless there is an active fault in
the area which does not appear to be the case as all the faults have
long been mapped. The only remaining possibility is that there’s a
hidden fault scar that seismologists missed due to it being hidden by
vegetation or glacial deposits.
There
is nothing more that can be done at this point, apart from taking
down readings from seismic sensors the researchers set up a month
ago, about 150km south in the town of Kotzebue. This should provide
the Earthquake Center with much more accurate readings regarding the
depth and origin of every event and aftershock.
“At
this point, we don't really understand the nature of these
earthquakes,”
Ruppert told AP. When asked about a nearby mine less than 80km to the
north, she said the relationship between it and the swarm of quakes
is not very likely, because “all
mining activities are very near the surface… and all the
earthquakes are miles below the surface.”
The
events are a huge mystery and researchers are on the ready for a
larger earthquake; despite there being nothing to suggest it, events
like this are usually followed by a much larger temblor.
“It’s
a very tricky subject. This is a very unusual situation,”
Walton told the newspaper
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