Natural disaster, earthquake and volcano general discussion

[Lily]

Just starting up this thread for ongoing general discussion relating to volcanoes, earthquakes and other natural disasters affecting us locally and around the world.



I'll start off with a report of a 7.7M quake early this morning between New Zealand and Tonga

http://www.ga.gov.au/earthquakes/getQua ... 2&sta=NIUE" onclick="window.open(this.href);return false;

Kermadec Islands Region, Kermadec-Tonga-Samoa Area.
Magnitude: 7.8 (Mwp)
Depth: 0 km
Tsunamigenic: Notified
Visit Tsunami Warning Centre Website

Date and Time
UTC: 06 July 2011 @ 19:03:10
AEST: 07 July 2011 @ 05:03:10

Location
Coordinates: -29.567, -175.141

Solution status
Last updated: 07 July 2011 @ 05:21:53 (AEST)
Solution finalised: No
Source: AUST

[Jake Smethurst]

Thanks Lily.

Yes I read about that on the news this afternoon. Lucky there was generally not damage as it was away from most populated areas, however a tsunami warning was issued for as far away as New Zealand, but later cancelled.

The BoM mentioned this:

Australian Government Bureau of Meteorology

MEDIA:
NO USE OF STANDARD EMERGENCY WARNING SIGNAL (SEWS)
PLEASE BROADCAST THIS INFORMATION IF REFERRING TO THE EARTHQUAKE IN NEWS
REPORTS.
********************************************************************************
NO TSUNAMI THREAT TO AUSTRALIA
Issued by the Joint Australian Tsunami Warning Centre (JATWC) at 5:18 AM EST on
Thursday 07 July 2011
********************************************************************************
SUMMARY:
An undersea earthquake of magnitude 7.8 has occurred at 5:03 AM EST on Thursday
07 July 2011 near KERMADEC ISLANDS REGION.
THERE IS NO TSUNAMI THREAT TO THE AUSTRALIAN MAINLAND, ISLANDS OR TERRITORIES.
For further information check the Bureau's website http://www.bom.gov.au/tsunami" onclick="window.open(this.href);return false; or
call 1300 TSUNAMI (1300 878 6264).

No further updates will be issued unless the situation changes.
********************************************************************************
DETAILS:
An undersea earthquake of magnitude 7.8 has occurred at 5:03 AM EST on Thursday
07 July 2011 near KERMADEC ISLANDS REGION (latitude 29.570S longitude 175.140W).
The JATWC has assessed that there is NO TSUNAMI THREAT TO THE AUSTRALIAN
MAINLAND, ISLANDS OR TERRITORIES from this earthquake.

No further updates will be issued unless the situation changes.

FOR FURTHER INFORMATION:

Call 1300 TSUNAMI (1300 878 6264)
Check the Bureau's web site: http://www.bom.gov.au/tsunami" onclick="window.open(this.href);return false;

As for an interesting article that was in our local paper, the Warrnambool Standard, and also on The Age website, about volcanoes overdue for an erruption in western Victoria. Interesting that I live in the vicinity of 2 of the most likely ones, less than an hour in fact. I have slow internet at the moment, so I cannot load any links just yet, but once we get faster internet tomorrow, I will provide the link.

[Lily]

Would love to see the article Jake. Might go and hunt, see if I can find something Thanks for the info re: tsunami threat, I noticed earlier this morning the tsunami threat was noted but no result, I did wonder about NZ as it was reasonably close to the north island.

[Lily]

From TVNZ, seems to have been some confusion over tsunami warnings issued there earlier this morning http://tvnz.co.nz/world-news/tsunami-wa ... on-4289781" onclick="window.open(this.href);return false;

Tsunami warnings cause confusion

UPDATED 17:13
Published: 7:15AM Thursday July 07, 2011 Source: ONE News
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Boats float in muddy water from tidal surges in Tutukaka Harbour in Northland - Source: ONE News

Source: ONE News
Watch Video
VIDEO: Tidal surge in Tutukaka (3:42)
Related
12:48 Quake off Kermadecs - Midday update (2:50)
08:35 CD's David Coetzee updates on NZ tsunami warning (3:53)
08:43 Pacific Tsunami Warning Centre's Barry Hirshorn (2:19)


Questions are being asked about how ready New Zealand is for a tsunami after a confused picture emerged from warnings today.

The warnings were issued after a big earthquake off the Kermadec Islands, some 1100 kilometres north of Auckland.

GeoNet now says the quake at 7.03am was magnitude 7.6, though initial recordings measured it at 7.8. It occurred just after 7am and its depth is now put at 20 kilometres. It was 12km from Raoul Island and 920km from Tonga.

* Amy Kelley has more on the impact of today's quake and the effectiveness of the tsunami warning which followed on ONE News at 6pm.

Civil Defence admits there was some confusion following the quake, with initial fears a tsunami could affect New Zealand.

The tsunami warning was later cancelled but Civil Defence has acknowledged there were mixed messages coming from them and the Pacific Tsunami Centre.

"Them using the word 'warning' is really the problem," said David Coetzee, Civil Defence National Controller.

"We want to get them to not to use that, rather just express the information in terms of what they know but not put our country under warnings."

But scientists say, in situations like this, Civil Defence are the experts all New Zealanders should be listening to.

GeoNet project director Ken Gledhill said: "All the tsunami warning centre is doing is saying it's giving a heads up, saying something's happened. It may have no impact in New Zealand, it may have severe impact in New Zealand. They're not really telling us what the impact will be, they're only telling us that something happens."

Civil Defence is still advising people to be cautious if they are entering water or going out in boats throughout New Zealand.

It says a "marine threat" remains in place with a one metre high tidal surge predicted between Northland and Hawke's Bay.

They are expecting there to be unusually strong tidal surges and currents until tomorrow morning.

And Civil Defence is now working with the Pacific Tsunami Centre, and reviewing their processes to eliminate confusing messages in the future.

Several boats took to sea and a marina under construction was shored up with ropes after this morning's tsunami warning at Tutukaka Marina on Northland's east coast.

In Auckland the water level of the Waitemata Harbour was about 30cm higher than normal, a Coastguard spokesperson told ONE News, while surges were seen this morning in Northland's Tutukaka Harbour .

Tutukaka Marina manager John Warren told ONE News half a dozen or so boats moved out to sea from the marina.

He said a couple of them tried to get back in later in the morning but the surges at the harbour entrance made it unsafe and they went back out into Pacific Bay.

Warren said the marina is currently being rebuilt at the moment and one pier which is the process of being constructed right now was particularly vulnerable because while the floating pontoons are in the water there are no piles holding it there.

"And so Total Marine, the company that's building it, very quickly got out and roped it up as best they could. And from then on it was just a matter of hoping the surges wouldn't be too bad."

Warren said the tsunami siren, recently installed at Snapper Rock, went off at about quarter to eight and the first surges came at about 9.30am.

"They weren't particularly bad. They were nowhere near as bad as the previous ones we've had, and the biggest of them was probably only about 300 millimetres."

Warren said tsunami surges seem to affect Tutukaka Harbour this harbour a lot more than other places around the country "and we think the reason is we have a very narrow entrance to the harbour".

He said: "Out at the entrance to the harbour proper is a very narrow gap and then once you get into the marine there's a breakwater and another very narrow gap. An it's just the quantity of water trying to get through a small hole."

A ONE News cameraman said the water was muddied when the surges came.

In Gisborne the story was the same with big ships coming into the bay taken further out and anchored in preparation for any waves.

'Fairly small' wave

After the tsunami advisory for the Pacific was cancelled, Barry Hirshorn of the Pacific Tsunami Warning Centre told Breakfast a "fairly small" wave was expected.

"The largest wave we saw was a peak to peak amplitude of 1.9 metres which, looking at the sea surface, would be like a one metre rise. That wave was at Raoul Island very close to the earthquake and just to the west of the epicentre.

"Further away from the quake it is very small to no tsunami. Based on that information it was clear that it was very small and we cancelled."

He said a quake of this nature could cause a tsunami but this earthquake was not a "thrust earthquake".

Civil Defence's David Coetzee told TV ONE there would not be a huge wave but there would be many swells and there is a marine threat.

For the next 24 hours people should exercise caution and discretion before entering the water or going out in small boats in all parts of New Zealand.

"We are not talking about one wave quickly and it's over, it will be pretty turbulent for the rest of the day," Coetzee said.
He said boaties should secure their boats.

"Boaties should stay moored up... It's better to move the boat out of the water if possible.

"We are not talking about significant land damage or that boats will be smashed, it's just a dangerous situation to be in the water."

He said any surge is likely to be about one metre high on current estimates.

"We have issued the warning to the whole of New Zealand but the areas from North Cape to Hawke's Bay are more prone today."

The Kermadecs lie 800km north of New Zealand and are uninhabited except for the permanently manned Raoul Island Station, the northernmost outpost of New Zealand. The station comprises a government meteorological and radio station and a Department of Conservation hostel.

Coetzee said some wave activity was confirmed in the Kermadecs. Department of Conservation staff and volunteers on Raoul Island felt the quake but there was no damage or injuries.

People in coastal areas should:
1. Stay off beaches
2. Stay out of the water (sea, rivers and estuaries, including boating activities)
3. Do not go sightseeing
4. Follow instructions of your local Civil Defence authorities.

[Lily]

Found that article Jake, hope you don't mind me posting here in lieu of your fast internet (that must be soooo frustrating for you!). You're right, interesting article with some hyperlinks to various volcanoes around the state.

Read more: http://www.theage.com.au/victoria/volca ... z1ROXUGFcG" onclick="window.open(this.href);return false;

Video: http://media.theage.com.au/news/nationa ... 75223.html" onclick="window.open(this.href);return false;

Volcanoes 'due to erupt'
Bridie Smith
July 6, 2011

Volcanoes 'due to erupt'
Victoria's volcanoes are overdue for an eruption, according to research that has dated the age of the cones, craters and lava flows with increased precision.

VICTORIA'S volcanoes are overdue for an eruption, according to research that has dated the age of the cones, craters and lava flows in the state's west with increased precision.

Using the latest dating techniques, scientists at the University of Melbourne established that, on average, the small volcanoes dotted from western Victoria to South Australia erupted every 2000 years.

The last eruption at Mount Gambier was more than 5000 years ago and Bernie Joyce, of the university's school of earth sciences, said that, statistically speaking, we were due for another.

Advertisement: Story continues below

In Victoria the most likely hot spots are Colac, Port Fairy and Portland while just over the border in South Australia, Mount Gambier is overdue for an eruption.
Presenting his findings at the International Congress of Geodesy and Geophysics in Melbourne yesterday, Professor Joyce said the most likely places for eruptions would be around Colac, Port Fairy, Portland and Mount Gambier.

He said eruptions close to Melbourne or Geelong were not out of the question either, as the Australian tectonic plate continued to move north at five centimetres a year.

''The plate is hitting up against PNG, lifting the southern margin upwards. This allows magma to move upwards towards the surface,'' Professor Joyce said.

The volcanoes that dot the landscape between Melbourne and Mount Gambier are monogenetic volcanoes - once-off volcanoes that deliver relatively small eruptions. There are 40 alone between Melbourne and Bacchus Marsh, with the last volcano to erupt in Victoria being Mount Napier, south of Hamilton.

Volcanoes in Victoria

Mt Noorat Crater, near Terang
Lake Bullenmerrie, near Camperdown
Tower Hill, near Warrnambool
Mt Elephant, near Derrinalum
Mt Macedon
Hanging Rock, near Woodend
Mt Kooroocheang, near Creswick
Mt Warrenheip, near Ballarat

[daviescr]

After the initial quake today in the Kermadec Islands, there has been another 14 aftershocks, that's close to one every hour! Average magnitude has been close to 5.0. I was thinking about inhabitants, but it appears there is no permanent inhabitants - just a handful of researchers at the Raoul island station - an NZ meteorology outpost. Some interesting info on Wikipedia

http://earthquake.usgs.gov/earthquakes/ ... 30_eqs.php

[Lily]

And now a 6.0 in the Kermadec Islands.

http://earthquake.usgs.gov/earthquakes/ ... 004pww.php" onclick="window.open(this.href);return false;


Magnitude
6.0
Date-Time
Thursday, July 07, 2011 at 09:10:52 UTC
Thursday, July 07, 2011 at 09:10:52 PM at epicenter
Time of Earthquake in other Time Zones
Location
28.941°S, 176.732°W
Depth
19.9 km (12.4 miles)
Region
KERMADEC ISLANDS REGION
Distances
119 km (73 miles) ENE of Raoul Island, Kermadec Islands
346 km (214 miles) NE of L'Esperance Rock, Kermadec Islands
878 km (545 miles) S of NUKU`ALOFA, Tonga
1185 km (736 miles) NE of Auckland, New Zealand

[daviescr]

Very interesting quake late last night in the Mediterranean, 160km of the west coast of Sardinia - Looking at the historical data, there's not been a quake in this location since at least 1900, and a M5.5 is pretty significant - was felt as far afield as Marseilles (237km) and Northern Italy (220km)

http://earthquake.usgs.gov/earthquakes/ ... 004qdn.php

[daviescr]

The kermadec cluster of quakes continue to rumble on today, with 23 quakes registered since the initial M7.3.

Here's an interesting write up on the region, and a PDF with some pretty pictures

The July 6, 2011 Kermadec Islands region earthquake occurred near the Kermadec Trench where the Pacific Plate begins its descent into the mantle beneath the eastern edge of the Australian Plate. At the latitude of this earthquake, the Pacific Plate is converging with Australia in a westward direction at a velocity of approximately 61 mm/yr. The preliminary mechanism and depth of the event suggest it ruptured a normal fault within the shallow oceanic lithosphere of the Pacific Plate; the initial location suggests a source slightly to the west of the trench, within the down-going slab, rather than to the east and in the outer rise.

The July 6 earthquake struck in an oceanic region with few nearby populations, approximately 550 km south of Tonga and 650 km north of New Zealand. This region of the Tonga-Kermadec subduction zone experiences reasonably high levels of seismic activity, with nearly 50 events of M 6.5 and above over the past 38 years, and 4 greater than M 7.5. Two of these, M 7.8 and M 8.2 earthquakes on the same day in 1976, occurred just over 150 km west-northwest of today's event; an M 7.8 event in 1978 struck nearly 200 km to the southwest, and an M 8.3 event occurred in October 1986, about 130 km to the north. None of these events have recorded damage or casualties.

[Rivergirl]

Yes the Kermadec Islands see a lot of earthquake activity. You would possibly think a tsunami could hit NZ from a large quake one day.

Interesting that quake in the Mediterranean Chris. I was watching a program on Mt Vesuvius a few weeks back and they said that it's expected to erupt in the next 10 years and that a sign of imminent eruption will be earthquakes then swarms before the eruption so that earthquake sounds significant. When I was there a couple of years ago our guide told us there is a 10 mile red area around the volcano where people have been asked to move but no one does. Millions of people will be affected when Vesuvius erupts. The Italian government has offered everyone $22,000 to leave their homes even in Sicily but of course no one takes that offer as its a pittance to what their homes are worth. Despite all the warnings more and more people gravitate to that region.

[Jake Smethurst]

Not a problem at all Lily, and we finally have fast internet again!!! It was an interesting article I thought that highlighted in particular that many of the volcanoes around our region are generally dormant, not extinct. I remember being in school and being taught that the volcanoes around our region were extinct, only to start listening to the news and researching, to find that they are in fact well and trully dormant. I often wonder what emergency plans are in place in case something decides to blow, I mean, if there was a very time for it to happen, it's probably from now; they are overdue, and look at the world, there seems to be natural disasters one after the other at the moment. I'd suppose the SES would be involved, since they educate people about earthquakes and thunderstorms, however I think there needs to be some education at least about the volcanoes, because you never know. We've just ignored them because nothing has happened over the past thousands of years.

As for the article you posted about the tsunami warning Lily, I totally agree with he NZ Civil Defence. I the Pacific Tsunami Warning Centre (PTWC) in my opinion, need to stop putting warnings out countries specifically, or at least to those countries of whom have their own tsunami warning system. It does confuse people. I remember the last few events here in Australia where a warning was in place by the PTWC, indicating there could be a tsunami, however the BoM were indicating there was no threat. Who to believe? is the question most people would ask. Nevertheless I think the PTWC does a good job, but perhaps they need to provide information to countries with warning systems already in place rather than specifically warn them. An interested debate could evolve out of this, I would love to get involved in one.

Robyn I find that volcano absolutely remarkable. I have always wanted to visit it, I'd imagine your trip there was amazing?

[Rivergirl]

All I want to do now is visit Hawaii to see Kilauea Volcano and then a trip to Iceland to see the volcanoes, preferably when one is erupting and then photograph the Aurora borealis

[crikey]

July 2011 INDONESIA
EXTRACT
INDONESIA will evacuate hundreds of people living near Mount Lokon on Sulawesi island after raising the volcano's alert status to the highest level.....

...The country's most active volcano, Mount Merapi in central Java, has killed more than 350 people in a series of violent eruptions which started in late October.

Read more: http://www.news.com.au/breaking-news/wo ... z1RnSFOSD8" onclick="window.open(this.href);return false;

[OHMegga]

Noticed a small but possibly significant increase this week in earthquake activity closer to the Tokyo area of Honshu Japan. The concern is that the Great Tokai earthquake may occur near Tokyo with devastating results. Most commentators seem to agree that the March 2011 megaquake and subsequent aftershocks have not reduced the chance of the Tokai quake but instead have increased the risk of it happening sooner. One can only hope this does not happen for a very very long time. Enough problems for Japan alreaady without anything as horrendous as this.
The links below are live updates so may not reflect the picture I am looking at today if you view in future.

http://earthquake.usgs.gov/earthquakes/ ... 140_35.php

http://www.jma.go.jp/en/quake_tokai/

[Lily]

This is a freakish coincidence. I taped the program on ABC the other night re: Japan earthquake, only got to watch it tonight. At the very end, they spoke about the "Big One" that is still believed to be just around the corner. Add to this that as I was watching the program, my brother who is visiting here on holidays and who resides in Tokyo, rang while I was watching the program to see if he could drop in and see us one more time before they returned back home. And now I come here and this is the first post I read!

I sure hope the scientists have it wrong this time The slightly good thing about this (on a very personal level) is that my brother lives in the hills so slightly elevated above sea level, which gives some (rather minor) comfort.

[crikey]

Thanks OHMega
It is always good to learn something new. I have never heard of the Great Tokai earthquake so l followed your links thanks.
Also read this
http://en.wikipedia.org/wiki/Tokai_earthquakes" onclick="window.open(this.href);return false;
and these two sentences caught my eye
Quote:
Concern has been expressed over the presence of the Hamaoka Nuclear Power Plant, close to the expected epicentre of a Tokai earthquake.[2]

and

The Japanese government is taking the Tokai earthquakes seriously

My comment
If you take these earthquakes seriously then why build a nuclear power plant on the expected epicenter
Dumb or criminal?

I suspect we will do the same in Australia and park a nuke plant where geographically we really shouldn't

LILY ..quite a coincidence. We all worry about our loved ones but lets face it there are many ways that we could lose them; accidents /sickness etc
Life's mostly great but sometimes its a right pain in the behind
cheers

[Rivergirl]

Thanks for the info OHMegga and crikey. Lily, you are having your share of coincidences lately. Some people call it synchronicity. I'm so glad your brother has been home for a bit so you could see him. I hope he stays safe.

[Lily]

Just got an alert for a 6.5 off the east coast of Japan http://neic.usgs.gov/neis/bulletin/neic_c0005gmg_l.html" onclick="window.open(this.href);return false;

[Rivergirl]

There seems to be a lot more activity in Katla volcano. Also I noticed today more swarms of earthquakes in REYKJANES RIDGE. They are much stronger than the last couple of days.

Here is a blog site with daily updates of Katla and earthquakes swarms

http://www.jonfr.com/volcano/