Tuesday, February 2, 2016

PLANETARY TREMORS: Strong Magnitude 6.6 Temblor Shake Near The Kermadec Islands Triggering "GHOST QUAKES" In North Island, New Zeland - But Why?!

Tuesday's earthquake was centred near the Kermadec's Raoul Island, about 1000km northeast of New Zealand.© Massey University

February 2, 2016 - NEW ZEALAND - The magnitude 6.6 quake that struck off the coast of the North Island on Tuesday was widely felt and triggered false reports of shakes in New Zealand.

It is not uncommon for earthquakes to confuse seismic readings as energy from tremors travels large distances.

These "ghost quakes" register as local earthquakes when the GNS Science system starts to receive data.


Seismic graphs show the earthquake waves at 8am on Tuesday detected by the northernmost seismographs.© John Ristau


Let's dive right in to the world of ghost earthquakes.

What happened on Tuesday?

A large magnitude 6.6 quake centres about 850 kilometres north of Whakatane at a depth of 360km.

The epicentre was near the Kermadec Islands and the Kermadec Trench.


The location of the quake. Deep quakes off the coast can be initially recorded as multiple quakes.© USGS


The United States Geological Survey located the earthquake 120km north-northwest of a barren outcrop known as L'Esperance Rock.


Below the North Island, the Pacific plate is subducting beneath the Australian plate, which causes deeper quakes.© GeoNet


ell me more about this part of the Pacific.

The trench is the fifth deepest point of the world's oceans.

It marks the point where the Australian plate meets the Pacific plate.


A national seismic trace shows the earthquake detected progressively, from Raoul Island southwards.© GNS Science


Geographically, the entire region is one of the most seismically active areas in the world.

So, about all that shaking people "felt" in New Zealand.


A still from the Raoul Island webcam on Tuesday at 9.20am.© GNS Science



New Zealanders felt the quake's energy, but it wasn't in New Zealand.

Seismographs interpreted the waves as locally sourced and triggered alerts for the North Island.

"Ghost" quakes sometimes appear on the seismic monitoring system, the GeoNet array of around 200 seismograms dotted around New Zealand, after a large regional earthquake.

Magnitude 6.6 is a big shake and has the potential to cause a disaster.

Sensitive equipment picks up the seismic waves created by earthquakes. Equipment gets confused and pushes out an earthquake alert interpreted as locally sourced to the public, when the shake could be hundreds of kilometres away.

As in this case?

Yes, the earthquake was around 1000km away and deep.

This is all a bit confusing.

It's simple.

As the seismic waves travelled south from the source they are picked up progressively by detectors.

First Raoul Island, which has a webcam by the way, picked up the earthquake then the network detected the waves as they quickly moved southwards.

The "ghost" or "false" quakes, reported on Tuesday as three severe quakes in the Bay of Plenty region, were removed from the GeoNet alert system after initial reports.

This kind of thing has happened before.


In 2013, a quake near the location of Tuesday's shake triggered ghost earthquake readings in New Zealand.

Why don't scientists wait to confirm an earthquake's location?

In short, it's important to get information and data out to the public quickly.

As soon as readings start coming in from the seismic network that information is automatically publicly notified.

Later, once GNS Science review data, they can revise the reported magnitude and pinpoint the precise location.

Let's get technical shall we?

OK, it's all about different types of seismic waves, known as P-waves and S-waves, and the types of detection equipment.

P stands for primary waves, S for secondary.

Broadly, the equipment confuses the secondary waves for primary shaking, hence the three severe shakes initially reported by GeoNet and felt by New Zealanders.

GNS seismologist Dr John Ristau says:

"People actually felt the quake. It was quite deep.

"Our automatic system, generally, for 99 per cent of the time it actually works quite well.

"We know there's a problem when we have large earthquakes north of the North Island, particularly when they are deep.

"Our automatic system gets fooled.

"Primary waves are the fastest. That triggers the system. Then you have the secondary waves. The S-waves come in well defined...so the automatic system gets fooled into thinking it's another earthquake."


Can scientists do anything about the confusion?

The current system is the best available.

Ristau says GNS Science would rather have the system detect earthquakes as false than re-calibrate it and risk failing to detect a locally-sourced shake.

Plus, it's important to get information out to the public as quickly as possible in New Zealand and the Pacific.

Seismograms are extremely sensitive aren't they?

They can pick up wind and traffic noise, so it's no surprise when they detect tremors from earthquakes hundreds, or even thousands, of kilometres away.

They picked up the Foo Fighters blasting Auckland in 2011, remember?

That area of the ocean sounds interesting.

The Kermadec Islands and the surrounding area lie within a marine sanctuary created in 2015.

Once fully enacted as a reserve by the Government in 2016, the sanctuary will be one of the largest and most protected marine regions in the world.

It's even possible to visit, although you'll need a permit. - Stuff.





ANIMAL BEHAVIOR: Disaster Precursors - Dog Kills Woman In Kamloops, Canada?!


February 2, 2016 - CANADA - The BC Coroners Service says a Tk'emlups Indian Band elder who died after she was mauled by a dog Saturday night was trying to feed her grandson's dog at the time.
RCMP and paramedics rushed to a property on West Shuswap Road Saturday night after being called by a frantic relative.

78-year-old Kathleen Green was pronounced dead at the scene.

"We would like to extend our deepest condolences to the family who have suffered a recent loss. She was a well respected elder in the community," says Chief Fred Seymour, Tk'emlups Indian Band. The dog was chained to a building at the time, but Corporal Cheryl Bush of Kamloops RCMP says those responding had to kill it in order to get to the woman.




"The dog was residing at the residence, not exactly clear on the ownership of the dog, and it was a mixed breed dog, and a fairly large dog," Bush told CFJC Today.

Regional Coroner Larry Marzinzik says the dog weighed about 27 kilograms or 60 pounds.

Marzinzik says investigators are still trying to nail down the chain of events.

"Our main focus right now will be on the cause of death itself, just seeing if the scene and the examination of the decedent will be able to help us determine the cause of death related to it, and then also just confirm the fact that it would have been from injuries received during the attack," said Marzinzik.


WATCH: Deadly dog attack in Kamloops.




The Tk'emlups Indian Band is in shock, counselling has been made available to help guide the community through this tragedy.

"The family would like to thank everyone for the well wishes and supports through this hard time. The family is deeply saddened and shocked by the tragedy that took place, and they ask that the community and media please respect their privacy at this time of mourning of their mother, grandmother, sister and aunt," says Chief Seymour.  - CFJC Today.





GLOBAL ECONOMIC MELTDOWN: Precursors To A Global Financial Collapse - Over 100 Walmart Stores Shut Down For Good In The United States In Small Towns And Rural Areas; A "Double Blow" For Many Frustrated Residents; Will Impact THOUSANDS Of Employees; Company Shares Down 25 PERCENT Over The Past 12 Months!


February 2, 2016 - UNITED STATES - More than 100 Walmarts around the country shut their doors Thursday for good -- many in small towns and rural areas with few other shopping options.

The retailer cites a long-term strategy shift and financial performance. Company shares are down 25 percent over the past 12 months, and the nationwide closures will also impact thousands of employees, reports CBS News correspondent David Begnaud.

"It's maddening because Walmart chose to do this," said resident Retha Thompson, who feels betrayed by Walmart's decision to leave Whitewright, Texas just 12 months after its grand opening. "They chose to come here and then when they put the other grocery store out of business, they want to close down and leave. I'm mad."

She's talking about "Pettit's," the mom and pop grocery that was a mainstay in this small town for nearly 60 years.

"Business - it just quit coming," Larry Deeds, the store's co-owner said.

Pettit's closed about nine months after Walmart opened.

"It's almost enough to bring a tear to your eye to see all these shelves empty," said Will Pettit, who worked here since he was 16.

When Walmart moved in last year, Whitewright's Mayor Allen West said a little competition from Walmart was a good thing. But now that it's leaving, "it's going to hurt the city financially, it's going to hurt the citizens economically and not good for their mental status," the mayor said.

Walmart is closing 154 stores in 27 states, many of them in small towns. In a statement to CBS News, Walmart said:
"The decision to close some of our stores was not easy and we share in the communities' disappointment. We're always searching for opportunities to serve more customers throughout the country -- especially those in underserved communities. We're now focused on where we can help impacted communities through our plans for charitable giving and expediting the process to work with potential buyers for these locations."
"Communities are finally getting a look at not only the effects of when Walmart comes into town, but also when they leave," said Bloomberg news reporter Shannon Pettypiece. "And I think that is a double blow for a lot people."

But Deeds said Walmart doesn't deserve all the blame.

"I lost some customers that had been coming to me for 20 or more years," Deeds said.

And now that Walmart is closed, Retha Thompson will drive half an hour to the closest grocery store.

"It won't be Walmart. I'm done with Walmart," Thompson said.

Two of Thompson's daughters-in-law were Walmart employees. They were offered either a severance package or the opportunity to relocate to work at another store, as goes for thousands of other employees across the country. - CBS News.






PLANETARY TREMORS: Very Strong 6.6 Magnitude Earthquake Strikes North Of New Zealand - Geonet! [MAPS + TECTONIC SUMMARY]

USGS earthquake location.

February 2, 2016 - NEW ZEALAND - A 6.6 magnitude earthquake 1100km off the North Island was responsible for the tremors that shook New Zealanders this morning.

Geonet seismologist John Ristau said the tremors felt in Bay of Plenty, Tararua and Canterbury were not official earthquakes.

There had been reports that a 5.3 magnitude quake was recorded 35 km south of Murupara and that 5.0 magnitude quake struck 20 km north west of Pongaroa.

A third quake was said to have hit 15km south-west of Amberley.


USGS shakemap intensity.

The shakes weren't official earthquakes but ripple effects of a 6.6. earthquake near Raoul Island.

Geonet received more than 500 reports of people who had felt shakes, Mr Ristau said.

There would be few aftershocks because the earthquake was so deep, he said.







Several people have reported feeling the quakes on social media, in areas including Bay of Plenty and Wellington.

Fire Service and police northern communications have received no reports of damage.

A spokesman for the Murupara police said he was outside when the earthquake was recorded as happening and he didn't feel a thing. He said there had been no calls from members of the public.

A woman spoken to at Murupara Area School was also surprised to hear reports of a quake - saying she didn't feel anything and nobody at the school had felt the quake. - New Zealand Herald.


Seismotectonics of the Eastern Margin of the Australia Plate

The eastern margin of the Australia plate is one of the most sesimically active areas of the world due to high rates of convergence between the Australia and Pacific plates. In the region of New Zealand, the 3000 km long Australia-Pacific plate boundary extends from south of Macquarie Island to the southern Kermadec Island chain. It includes an oceanic transform (the Macquarie Ridge), two oppositely verging subduction zones (Puysegur and Hikurangi), and a transpressive continental transform, the Alpine Fault through South Island, New Zealand.

Since 1900 there have been 15 M7.5+ earthquakes recorded near New Zealand. Nine of these, and the four largest, occurred along or near the Macquarie Ridge, including the 1989 M8.2 event on the ridge itself, and the 2004 M8.1 event 200 km to the west of the plate boundary, reflecting intraplate deformation. The largest recorded earthquake in New Zealand itself was the 1931 M7.8 Hawke's Bay earthquake, which killed 256 people. The last M7.5+ earthquake along the Alpine Fault was 170 years ago; studies of the faults' strain accumulation suggest that similar events are likely to occur again.


USGS plate tectonics for the region.

North of New Zealand, the Australia-Pacific boundary stretches east of Tonga and Fiji to 250 km south of Samoa. For 2,200 km the trench is approximately linear, and includes two segments where old (greater than 120 Myr) Pacific oceanic lithosphere rapidly subducts westward (Kermadec and Tonga). At the northern end of the Tonga trench, the boundary curves sharply westward and changes along a 700 km-long segment from trench-normal subduction, to oblique subduction, to a left lateral transform-like structure.

Australia-Pacific convergence rates increase northward from 60 mm/yr at the southern Kermadec trench to 90 mm/yr at the northern Tonga trench; however, significant back arc extension (or equivalently, slab rollback) causes the consumption rate of subducting Pacific lithosphere to be much faster. The spreading rate in the Havre trough, west of the Kermadec trench, increases northward from 8 to 20 mm/yr. The southern tip of this spreading center is propagating into the North Island of New Zealand, rifting it apart. In the southern Lau Basin, west of the Tonga trench, the spreading rate increases northward from 60 to 90 mm/yr, and in the northern Lau Basin, multiple spreading centers result in an extension rate as high as 160 mm/yr. The overall subduction velocity of the Pacific plate is the vector sum of Australia-Pacific velocity and back arc spreading velocity: thus it increases northward along the Kermadec trench from 70 to 100 mm/yr, and along the Tonga trench from 150 to 240 mm/yr.

The Kermadec-Tonga subduction zone generates many large earthquakes on the interface between the descending Pacific and overriding Australia plates, within the two plates themselves and, less frequently, near the outer rise of the Pacific plate east of the trench. Since 1900, 40 M7.5+ earthquakes have been recorded, mostly north of 30°S. However, it is unclear whether any of the few historic M8+ events that have occurred close to the plate boundary were underthrusting events on the plate interface, or were intraplate earthquakes. On September 29, 2009, one of the largest normal fault (outer rise) earthquakes ever recorded (M8.1) occurred south of Samoa, 40 km east of the Tonga trench, generating a tsunami that killed at least 180 people.

Across the North Fiji Basin and to the west of the Vanuatu Islands, the Australia plate again subducts eastwards beneath the Pacific, at the North New Hebrides trench. At the southern end of this trench, east of the Loyalty Islands, the plate boundary curves east into an oceanic transform-like structure analogous to the one north of Tonga.

Australia-Pacific convergence rates increase northward from 80 to 90 mm/yr along the North New Hebrides trench, but the Australia plate consumption rate is increased by extension in the back arc and in the North Fiji Basin. Back arc spreading occurs at a rate of 50 mm/yr along most of the subduction zone, except near ~15°S, where the D'Entrecasteaux ridge intersects the trench and causes localized compression of 50 mm/yr in the back arc. Therefore, the Australia plate subduction velocity ranges from 120 mm/yr at the southern end of the North New Hebrides trench, to 40 mm/yr at the D'Entrecasteaux ridge-trench intersection, to 170 mm/yr at the northern end of the trench.

Large earthquakes are common along the North New Hebrides trench and have mechanisms associated with subduction tectonics, though occasional strike slip earthquakes occur near the subduction of the D'Entrecasteaux ridge. Within the subduction zone 34 M7.5+ earthquakes have been recorded since 1900. On October 7, 2009, a large interplate thrust fault earthquake (M7.6) in the northern North New Hebrides subduction zone was followed 15 minutes later by an even larger interplate event (M7.8) 60 km to the north. It is likely that the first event triggered the second of the so-called earthquake "doublet".

More information on regional seismicity and tectonics

- USGS.