Tag Archives: tsunami

New Zealand’s mysterious ‘silent earthquake’ could help predict future tsunamis | Instant News


New Zealand

What is slow slip? Video / GNS Science

An earthquake that occurs slowly and quietly deep beneath the North Island can be the key to predicting future earthquakes and tsunamis generated by our biggest fault.

A million dollar, three-year project will increase scientists’ understanding of
Earthquakes “slow” along the Hikurangi Subduction Zone.

Scientists believe the subduction zone, which runs along the east coast of the North Island, could produce “megathrust” earthquakes larger than the scale of 8, such as the one that created the tsunamis that devastated Indonesia in 2004 and Japan in 2011.

The worst case scenario of a major Hikurangi event could include thousands of deaths and injuries, and billions of dollars worth of property losses.

But slow-slip earthquakes – where plate boundary faults release slowly buried tension over days to months instead of seconds in a typical earthquake – can help us better gauge threats.

Their discovery 20 years ago has revolutionized seismology and our understanding of fault mechanics.

Even though it happens off the east coast every few years, no one feels it when it happens – and the driving force remains unclear.

The new project, led by GNS Science, is designed to detect subtle physical changes in a fault before a slow-slip earthquake occurs, to uncover the mechanisms that regulate its timing.

“It will clarify if there is an observable physical change in the fault that could allow the development of a more accurate estimate of when the fault might fail, either in a slow earthquake or, possibly, a fast earthquake,” said project leader Dr Laura Wallace.

Tantalizing evidence has emerged in recent years that increased water pressure near the fault exerts great control over New Zealand’s slow-slip earthquakes.

GNS seismologist Dr Emily Warren-Smith said if this build-up affects slip times, then monitoring water accumulation in the fault could allow better forecasts for slow and possibly fast earthquakes in the future.

But it is possible that the change in fluid pressure within the fault may be a symptom of a slow earthquake rather than a direct cause, said Wallace.

Alternatively, there may be other processes such as a steady increase in stress from tectonic plate motion that controls the tempo of a slow slip earthquake.

The project aims to resolve this dichotomy by installing large-scale submarine and land monitoring instruments in the southern Hawke’s Bay and Wairarapa.

It will monitor changes before, during and after the regularly expected recurring slow slip events offshore in this region in the next two years.

This picture illustrates where "slow slip" previous earthquakes occurred under the North Island.  Image Science / GNS
This image depicts where a previous “slow slip” earthquake occurred beneath the North Island. Image Science / GNS

Wallace said the project would establish new ground in seabed geodesy and help put New Zealand at the forefront of global efforts to monitor offshore faults that can produce large earthquakes and tsunamis.

The team departed this weekend aboard the Niwa research vessel Tangaroa to carry out the first set of seabed sensor deployments.

“This project will generate new evidence-based information that will aid significantly in planning and preparedness and make New Zealand safer and more capable of recovering from a major earthquake.”

A separate voyage to the Hikurangi subduction zone – where the Pacific Plate is plunging downward, or “plunging” below the North Island’s east coast – has just finished.

US scientists recently dropped their own specialized equipment onto the ocean floor to visualize subsurface structures, and investigated how fluid is distributed within the sediments.

The Hikurangi subduction zone is where the Pacific tectonic plate sinks into - or dives beneath - the Australian tectonic plate.  Image Science / GNS
The Hikurangi subduction zone is where the Pacific tectonic plate sinks into – or dives beneath – the Australian tectonic plate. Image Science / GNS

Program leader Dr Jess Hillman, from GNS Science, said this will allow scientists to better understand how fluid movement is related to activity in our largest offshore faults and the generation of gases beneath the ocean floor.

Shipping specialist Dr Peter Kannberg, from the Scripps Institution of Oceanography in the US, said earthquakes, the stability of the seabed slopes and the release of seabed gases were all regulated in part by the presence of fluids.

“Our instrumentation can detect where this fluid is on Earth, enabling us to better understand the role of fluids in regulating these natural hazards.”

The new three-year project is supported by a $ 960,000 grant from the Marsden Fund.

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Country facing a tsunami of unemployment, inflation: Kaira | Instant News


SIALCOT: Central Punjab PPP President Ch Qamar Zaman Kaira claims that the public gathering of the Pakistan Democratic Movement in Gujranwala on October 16 will be the largest in the city’s history.

He said this while addressing the board of the PPP’s different wings at the residence of the district general secretary of the Khan Shahbaz Khan party here on Monday. Former MPA Malik Tahir Akhtar, advocate vice president of PPP Punjab Kh Awais, advocate for district president Azhar Hassan, advocate for city president Azhar Dayal, city secretary general Malik Ali and a number of local leaders and workers were also present. Qamar Zaman Kaira said that PPP, PML-N, JUI-F and other parties worked hard to make the meeting a success.

He claimed the government had failed to fulfill the promises made with the masses during the 2018 election campaign. He added that the Pakistani people know very well that the current administration for the past two and a half years has made their lives miserable.

Kaira said Prime Minister Imran Khan had repeatedly blamed and criticized the past governments of the PPP and PML-N for the circular debt, which now during his own term has reached a staggering figure of more than Rs 2,400 billion.

He said Imran Khan rightly used to say he would launch a tsunami in the country because currently Pakistan is in the tight grip of the worst tsunami of unprecedented unemployment, rising prices, inflation and political and economic instability. He said that before forming a government, Imran Khan and his colleagues had promised time and time again that they would return $ 200 billion to the country, which they said had been plundered by so-called corrupt PPP politicians. PML-N and JUI-F, but ironically, they didn’t bring home not even a dollar.

He said false claims about alleged corruption by rival politicians and empty promises to improve conditions for the poor had exposed the leadership of the PTI to the Pakistani people. Qamar Zaman Kaira said that the NAB cannot see those responsible for the rising prices of flour and sugar. Qamar Zaman Kaira said that his party chairman Bilawal Bhutto, who firmly believes that Imran Khan was elected by certain strong corners, at the first session of the National Assembly had offered full support and cooperation to the PTI government to strengthen democracy in the country. . He said that after witnessing the government’s inability to deliver, most of the major political parties had jointly decided to launch a united and resolute movement to remove the government. He called the Democracy Charter (CoD) a historic and vital agreement between two major political parties to strengthen democracy in the country. He explained that the CoD had not ended the fierce competition between political parties, but had greatly minimized it.

He said that running the country in accordance with the constitution was very important to put it on the path of progress and prosperity. He was of the opinion that all state institutions must act within the limits stated in the constitution in the interests of the state.

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