Earthquakes
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Chalkboard

Mathematician claims one in 500 chance of extinction next year

Alexandra Sims
The Independent, UK
Sat, 19 Nov 2016 16:17 UTC
Earth
© NASAThe calculation is based on the Doomsday Argument.
The human race faces a one in 500 chance of extinction in the next year, an expert mathematician has claimed.

Dr Fergus Simpson, a mathematician at the University of Barcelona's Institute of Cosmos Sciences, said there was a 0.2 per cent chance of a "global catastrophe" occurring in any given year over the course of the 21st Century.

The calculation is based on the Doomsday Argument, which it is claimed can predict the number of future members of the human species given an estimate of the total number of humans born so far.

"Our key conclusion is that the annual risk of global catastrophe currently exceeds 0.2 per cent," Dr Simpson wrote in an academic paper called Apocalypse Now? Reviving the Doomsday Argument, accessed through Cornell University's online library.

"In a year when Leicester City FC were crowned Premier League champions, we are reminded that events of this rarity can prove challenging to anticipate, yet they should not be ignored," he added.

According to Dr Simpson's calculations, around 100 billion people have already been born and a similar number will be born in the future before the human race expires.

He estimated there was a 13 per cent chance humanity would fail to see out the 21st Century.

This is a more optimistic conclusion than previous studies, with British Astronomer Royal Sir Martin Rees suggesting there was a 50 per cent probability of human extinction by the year 2100 in his 2003 book Our Final Hour.
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Info

New Zealand's 'unusual' earthquake raises complex questions

Ake Fagereng
Eos
Fri, 18 Nov 2016 21:23 UTC
New Zealand 7.8 earthquake map
© Google Earth/ GNS ScienceThe 2016 Kaikoura earthquake was a magnitude 7.8 (Mw) earthquake in the South Island of New Zealand that occurred two minutes after midnight on 14 November 2016 NZDT (11:02 on 13 November UTC).

A devastating earthquake has hit New Zealand, but this unusual event, with long duration slip on several faults, will also provide an astounding data set for understanding a complex tectonic region.

New Zealand was rocked by a magnitude 7.8 earthquake on Monday 14th November. This event had unusual aspects of slip distribution, duration, and kinematics, from which we will learn a lot about earthquake mechanics as data are collected. The event that started ~100 km north of Christchurch with displacements less than 1 m, propagated northward, creating the largest surface displacements (so far observed) near the northern termination of the earthquake rupture, at the northeast tip of the South Island.

At this early stage, based on preliminary data released by the New Zealand monitoring partnership GeoNet, I find three properties of the earthquake particularly intriguing:

1. Slip distribution.

The large surface displacement at the northern end of the rupture explains why aftershocks are concentrated in the north, and why areas north of the rupture, such as Wellington, experienced more damage than Christchurch, which is closer to but south of the epicenter.

The earthquake adds insight to the discussion of whether an earthquake knows its size when it nucleates - this earthquake started small, and only reached large slip late in its propagation. The USGS estimates the greatest displacements were over 100 km from the epicenter.

Therefore, as suggested in recent findings by Meier et al., there seems to have been no way to expect the large size of this earthquake from its small early slip. The question remains, why did the earthquake start small and get larger?

Comment: See also:

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Seismograph

New Zealand Quake Ruptured 6 Faults

Tia Ghose
Live Science
Wed, 16 Nov 2016 23:57 UTC
New Zealand Earthquake
© GNS ScienceA new map reveals that six faults ruptured during the Nov. 14 Kaikoura earthquake in New Zealand. The magnitude-7.8 quake ruptured at least four faults along the coast, as well as two inland. Arrows show the level of displacement along each of these faults.
The magnitude-7.8 quake that rattled New Zealand, killing at least two people and stranding thousands of people, completely transformed the underlying faults in the region.

Six major faults ruptured as a result of the New Zealand quake, a new map reveals.

The Kaikoura earthquake struck the South Island of New Zealand early in the morning on Nov. 14 local time, triggering landslides, tsunamis and hundreds of aftershocks. And thousands of people were stranded when earthquake detritus dammed a river. During the quake, bystanders captured images of mysterious earthquake lights painting the sky in eerie blue and green.

To see how the massive temblor reshaped the landscape, Nicola Litchfield, a geologist with the geoscience consultancy group GNS Science in New Zealand, and colleagues flew over the South Island in a helicopter to take video footage of the region.

Comment: See also:

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Question

Mysterious 'phantom earthquake' reported in San Jose, California

Dianne de Guzman and Amy Graff
SFGate
Wed, 16 Nov 2016 20:34 UTC
Phantom earthquake in San Jose
© twitter/Rakesh
South Bay residents felt some shaking Tuesday afternoon, however the exact cause is unknown.

The U.S. Geological Survey confirmed that what South Bay residents felt was not an earthquake.

"Our duty seismologist did an extensive search and we did not see any seismic activity in the South Bay," Susan Garcia, a spokeswoman with the U.S. Geological Survey, said to SFGATE. "So it's not an earthquake, whatever they're feeling — as far as we can tell."

Despite that, many local residents did report on Twitter that a rumbling of some sort was felt at about 2:45 p.m.

Comment: Reports of a sonic boom being responsible for the mysterious shaking also appear to have been discounted. "Based on initial reports we're receiving, it's inconsistent with a military sonic boom taking place," Marc Calero, a spokesperson for the Naval Air Station at Lemoore said Wednesday evening. "The way people have described it seems highly inconsistent with a sound barrier being broken."

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Bizarro Earth

Scientists confirm Monday's earthquake in New Zealand lifted seabed 'by at least a metre'

Jamie Morton, Belinda Feek
NZ herald
Tue, 15 Nov 2016 08:39 UTC
Tectonic uplift of the sea bed
© Twitter/TonkinTaylorAerial photographs taken showing tectonic uplift of the sea bed of between 2 and 2.5 metres north of Kaikoura.
Monday morning's quake has lifted the seabed around Kaikoura by at least a metre, scientists have confirmed. Although a scientific rarity, it's a phenomenon that those in the tourism industry are saying will spell doom for them and their jobs. Local boat skipper Dean Kennedy said he'd never seen anything like it in his 50-odd years.

He was at South Bay wharf today about 90 minutes before low tide making sure he was seeing correctly. He said the explanation was simple - and it wasn't good.

"Our summer is buggered. We're all out of a job pretty much."

Kaikoura was dependent on tourists and fish, including crayfish, and there wouldn't be any of them around for a few months, he said.

"Normally it's busy, flat out. There are four whale watching boats, three charter fishing boats and three dolphin-watching boats, and long weekends and Christmas we get recreational fishing boats from Christchurch."

But now, instead of diving for paua, the seafood beds had been left exposed by the rise in the sea floor.
All the kaimoana that's in that zone is going to die, probably and even the stuff that moves down that's not the environment it likes to live in.

Dean Kennedy, boat skipper
"Normally where we go diving people are walking out and picking them up.
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Bizarro Earth

Double tectonic shifts may have teamed in New Zealand's recent earthquake

James Regan and Jamie Freed
Yahoo News
Mon, 14 Nov 2016 00:00 UTC
new zealand earthquake november 2016
The powerful earthquake that struck New Zealand was unusual in that a big event on one fault may have immediately triggered a big event on a second fault, experts said on Monday.

An earthquake of magnitude 7.8 pummeled central New Zealand at 12.02 a.m., killing at least two people, damaging roads and buildings and setting off hundreds of strong aftershocks.

"When an earthquake occurs you are changing the stress field immediately, and if there was one fault that was pretty close to breaking, the energy from an earthquake can just tip it over the edge so that may have been what happened today," Adam Pascale, head of Australia's Seismology Research Centre, told Reuters.

New Zealand's GNS Science agency principal scientist Kelvin Barrowman told Radio New Zealand: "It seems like the earthquake was more like two earthquakes, but very closely spaced in time."

What remains unknown, and disconcerting, is whether the high number of aftershocks were just that, or "foreshocks" preceding another large quake.

Comment: Large earthquakes can trigger aftershocks on separate faults within moments causing greater damage

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Attention

Up to 100,000 landslides and hundreds of tremors after powerful New Zealand earthquake

Eleanor Ainge Roy
The Guardian
Tue, 15 Nov 2016 06:30 UTC
Cows stranded in New Zealand
© News hubA family of cows were left stranded after the massive New Zealand earthquake caused a landslide
Relief efforts continue around main affected town of Kaikoura, while aftershocks reach Wellington region, also hit by storms and flooding

Up to 100,000 landslides were caused by New Zealand's 7.8 magnitude earthquake, officials said, as aftershocks continued to shake parts of both islands of New Zealand and emergency crews worked to help people in the main affected areas.

A major relief effort continued on Tuesday, with thousands of people stranded by the quake, which blocked roads and damaged many buildings across parts of the North and South islands.

Emergency services and defence personnel were evacuating hundreds of tourists and residents from Kaikoura, the heavily hit South Island town, amid more strong aftershocks on Tuesday.

The powerful earthquake killed two people. It struck just after midnight on Sunday, destroying farm homesteads, sending glass and masonry toppling from buildings in the capital, Wellington, on the North Island and cutting road and rail links throughout the north-east of the South Island.


Comment: See also:

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Arrow Up

Shallow 6.1 magnitude earthquake in Sulu Sea near Philippines


Volcano Discovery
Mon, 14 Nov 2016 03:37 UTC
6.1 earthquake in Sulu Sea
© Google/Volcano Discovery
Date & time: Mon, 14 Nov 00:42:03 UTC

Magnitude: 6.1

Depth: 5.0 km

Epicenter latitude / longitude: 7.26°N / 119.44°E [Map]

Nearest volcano: Jolo (226 km)

Primary data source: GFZ
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Seismograph

6.2 aftershock rattles New Zealand after powerful 7.8 earthquake kills at least 2


RT
Mon, 14 Nov 2016 01:01 UTC
Earthquake damage in New Zealand
© Anthony Phelps / Reuters Local residents Chris and Viv Young look at damage caused by an earthquake along State Highway One near the town of Ward, south of Blenheim on New Zealand's South Island, November 14, 2016.
A new earthquake measuring 6.2 has struck 39km west of Kaikoura, New Zealand. This is one of the most powerful in a series of tremors that followed a 7.8 magnitude quake which struck the town, located some 180km northeast of Christchurch, on Sunday.

The quake took place at around 12:30am GMT at a depth of 8.3 kilometers, and was initially measured at 6.8, but was later downgraded to 6.2 by USGS.

Meanwhile GeoNet, the official source of geological hazard information for New Zealand, measured the latest quake at 6.3 and said its depth was around 35 kilometers.

At least two people were killed following the initial quake which struck New Zealand just after 11:00am GMT on Sunday (12:02am Monday local time).

The ministry of civil defense immediately issued a warning saying that a "destructive tsunami" with waves of up to five meters (16 feet) was possible. The ministry treated the possibility of a tsunami as "an event of life-threatening or national significance."


Comment: See also:

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Bizarro Earth

Strange glowing in the sky during New Zealand's earthquake possibly 'earthquake lightning'

John Edens
Stuff.co.nz
Mon, 14 Nov 2016 02:46 UTC

What was that strange light in the sky? Many people overnight reported seeing strange lights in the sky, a phenomenon that has been reported for centuries before, during, and after earthquakes.

Seismologists aren't in agreement about the causes of the hotly-debated phenomenon - called earthquake lights or, sometimes, earthquake lightning.

Earthquake Damage Canterbury
© Iain McGregor/Fairfax NZMajor damage caused by the 7.5-magnitude earthquake in Canterbury.
And, of course, it's not clear whether the lights overnight in New Zealand were the phenomenon, or something else. One theory suggests dormant electrical charges in rocks are triggered by the stress of the Earth's crust and plate tectonics, transferring the charge to the surface where it appears as light.

Historical reports include globes, or orbs, of glowing light, floating just above the ground or in the sky.
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