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message 1: by Nik (new)

Nik Krasno | 16032 comments Through the entire history of humanity earthquakes and volcano eruptions erased man-made constructions and sometimes whole settlements, if not countries. Yeah, there are efforts to predict e/q, but not sure how precise or reliable those seismic dudes are.
Anyhow, have you experienced and e/q? Can they be artificially induced for military or other purposes in your opinion?


message 2: by Leonie (new)

Leonie (leonierogers) | 1579 comments I can just remember the Meckering Earthquake when I was a child in Western Australia. http://www.allshookup.org/swsz/histor...

And then the Cadoux quake when I was at high school. https://en.wikipedia.org/wiki/Cadoux,...

And we're currently in New Zealand, and drove through the Kaikoura region a few days ago. There was a massive earthquake there in 2016, requiring the complete reconstruction of significant portions of the national road, along with many buildings. https://en.wikipedia.org/wiki/2016_Ka...

Certainly as a kid growing up in WA, we had semi regular earth tremors - frequently enough that we did 'earthquake drill' at school on occasion.


message 3: by Michel (new)

Michel Poulin The only way to artificially induce an earthquake is by detonating an atomic bomb deep underground. Even then, it won't produce a truly powerful earthquake. Natural earthquakes release a tremendous amount of energy, the kind of energy only a planet can deliver. If you have an atomic bomb and want to cause widespread damage, then don't waste it trying to create an earthquake, detonate it above ground.


message 4: by Ian (new)

Ian Miller | 11768 comments I live beside a major fault line (it is just down there - viewable from window, although you can't specifically see it .) And yes, I experience earthquakes from time to time - the most inconvenient was the one that Leonie mentioned because it happened the night after I got home from hip replacement surgery, I had my sister here to help me, we lost electricity, and I was the only one familiar with the house - from memory it was a little after midnight.

You can't predict them, accurately enough to do anything about them — the main alpine fault in the Sth Island will go something like every 350 yrs or so (latest estimate I have heard, but it does vary) and it is more or less due to go now, but it could take another hundred years. Predictions on the fault outside my window vary by hundreds of years, the reason being that around here there are about four roughly parallel faults, and who knows which one will actually go?

Small earthquakes can be triggered by subsidence - I believe in parts of the US there are some due to the removal of oil and gas or of fracking - take away some of what was there and there is the possibility of collapse. Large earthquakes could be triggered possibly by a large explosion if it were on a fault that was more or less ready to go anyway, but as Michel points out, the strain energy stored in fault lines can be huge. In my case, to the east a lump of basalt the size of the Pacific ocean is being pushed under a limp of rock that, to the West, includes Australia and I think goes up towards India. The rock at the junctions has huge forces put on it if it refuses to move, and while the rest is moving, the strain energy is huge until something gives.


message 5: by J.J. (new)

J.J. Mainor | 2328 comments It wasn't big, but a 5.8 struck in Virginia back in 2011. Didn't really feel it down here, but it sounded like a very low flying helicopter came through for about a minute.


message 6: by Scout (new)

Scout (goodreadscomscout) | 6151 comments Very scary - the earth moving under your feet.


message 7: by J.J. (new)

J.J. Mainor | 2328 comments You're in Georgia, right? Didn't you experience it a little? I remember the thing was felt all up and down the East Coast.


message 8: by Scout (new)

Scout (goodreadscomscout) | 6151 comments No, read about it but didn't feel it, thank goodness.


message 9: by J.J. (new)

J.J. Mainor | 2328 comments Ha ha...would have been a novelty. I think the only damage was in the immediate area around the epicenter.

Now the tornado that came through here the same year...that was frightening.


message 10: by Leonie (new)

Leonie (leonierogers) | 1579 comments Ian wrote: "I live beside a major fault line (it is just down there - viewable from window, although you can't specifically see it .) And yes, I experience earthquakes from time to time - the most inconvenient..."

We just drove back down the Kaikoura coast - amazing recovery work done on the roads, Ian. Do you live in the South Island?

We're currently parked in our camper van in the Akaroa crater, which is on topic, really, given that it was once (possibly still is) a volcano. Spectacularly beautiful.


message 11: by Graeme (new)

Graeme Rodaughan Michel wrote: "The only way to artificially induce an earthquake is by detonating an atomic bomb deep underground. Even then, it won't produce a truly powerful earthquake. Natural earthquakes release a tremendous..."

I don't know? Apparently, Ming the Merciless could cause earthquakes at will. This historical footage at IMDB explains all : https://www.imdb.com/title/tt0080745/


message 12: by Ian (new)

Ian Miller | 11768 comments Leonie, I am glad you are enjoying your vacation in NZ. The general feeling about the Banks Peninsula volcanoes are that they are extinct as they haven't done anything in, I believe, the last 3 million years. If you want to see a scary volcano, you come to the North Island - Taupo to be precise. It is a supervolcano and the lake is a caldera that takes over half an hour to drive from one end to the other. When it goes, the massive lake will drop into the magma so it must be a huge bang.

I live in the North Island. Lower Hutt, to be specific, which is a city associated with Wellington - the north part of the harbour. Because the terrain here is mangled by massive earthquakes, there are five cities more or less part of Wellington, but separated by terrain too steep to build on.


message 13: by Nik (new)

Nik Krasno | 16032 comments Is a global e/q with one or multiple epicenters something that can happen?


message 14: by Ian (new)

Ian Miller | 11768 comments As I understand it, no. An earthquake is very local. One place on the fault line gives way and all that energy is released as it moves. The problem then is that when that part moves, the next part that has not moved takes up a lot more strain energy, and soon it cannot take it so it moves, which is why you get a lot of aftershocks of decreasing amplitude (because the waves going out also disperse energy) Occasionally, there is a further zone that already has a lot of stored energy, so it may give an even bigger one if enough energy was there as strain already.

One thing to remember is the plates generally slip past each other, and only lock at specific awkward points. Where they have been slipping, the big on will cause more sudden slipping, but no strain is stored. The lockage points are not linked in any way, so some global event is essentially impossible except, I suppose with the waves given off by some extinction event like a massive asteroid hitting Earth. When the collision that caused the Moon to form occurred there would have been a big global shaking.


message 15: by Leonie (new)

Leonie (leonierogers) | 1579 comments Ian wrote: "Leonie, I am glad you are enjoying your vacation in NZ. The general feeling about the Banks Peninsula volcanoes are that they are extinct as they haven't done anything in, I believe, the last 3 mil..."

Did a lovely cruise to see Hector's Dolphins today, and that was the information provided about the Banks Peninsula volcanoes, Ian! You can see various old lava flows in the exposed strata around the harbour, interspersed by ash layers - absolutely fascinating,

Some of the information in Kaikoura explained that the earthquake affecting that region was initiated by a quake in Culverden, quite a ways inland and to the south, which subsequently set off 28 different faults. Apparently some were known faults, but others were discovered as a result of the quakes.


message 16: by Leonie (new)

Leonie (leonierogers) | 1579 comments And I had no idea about Wellington's bits and pieces. I have a friend who was skiing on Ruapehu last time it blew its top.

I asked what they did, and she said that there weren't really a lot of options except to pause and watch. Fortunately they were on the relatively 'safe' side.

Taupo does sound overly 'exciting.' We were just discussing campervanning around the North Island. One of the fascinating things about volcanoes and earthquakes is the difficulties in accurate prediction. Or prediction at all, really.


message 17: by Graeme (new)

Graeme Rodaughan Hi all, is there anything to the idea that the ring of fire is currently undergoing an active phase?

(With possibly catastrophic outcomes).


message 18: by Nik (new)

Nik Krasno | 16032 comments Leonie wrote: "...campervanning around the North Island.."

An RV in NZ should be lots of fun. Have friends here who've done it and enjoyed immensely. Hope you have an excellent trip without any ongoing natural calamities -:)


message 19: by Nik (new)

Nik Krasno | 16032 comments Graeme wrote: "Hi all, is there anything to the idea that the ring of fire is currently undergoing an active phase?

(With possibly catastrophic outcomes)."


Wiki ascribes the majority of earthquakes and volcanoes to it, so if anything's active the Ring of Fire must be https://en.wikipedia.org/wiki/Ring_of...

Hope for no catastrophes though


message 20: by Ian (new)

Ian Miller | 11768 comments Leonie, I don't know how long you are going to be here, but if you are campervanning, you should try to see the West Coast. It really does have the most spectacular scenery. I could suggest a route if interested.

As for the Nth Island, let me know if you are staying in Wellington and want to see me. As for Taupo, it is really violent, but not very often. Ter ecan be spells of up to 35,000 yrs between explosions, the last one was about 2,000 yrs ago, and when it does go, it should give lots of warning. The thermal areas around Taupo/Rotorua are really interesting, but quite safe.


message 21: by Ian (new)

Ian Miller | 11768 comments Graeme wrote: "Hi all, is there anything to the idea that the ring of fire is currently undergoing an active phase?

(With possibly catastrophic outcomes)."


Hi Graeme,

Almost certainly not. It is all probability - there is always activity, and when each site is independent, there are a lot of sites, there are always periods where it appear to be more active, but that is just probabilities. Like tossing coins ten times. Going HTHTHT.... is very improbable, as I am sure you know. There are always some bunches.


message 22: by Scout (new)

Scout (goodreadscomscout) | 6151 comments Oh, Leonie, sounds like a great trip. Hope you enjoy every moment.


message 23: by Leonie (new)

Leonie (leonierogers) | 1579 comments Ian wrote: "Leonie, I don't know how long you are going to be here, but if you are campervanning, you should try to see the West Coast. It really does have the most spectacular scenery. I could suggest a route..."

Thanks, Ian. This is actually our third trip to NZ, as my husband actually grew up here.

We've wandered the West Coast of the South Island extensively previously, so this time we restricted ourselves to the northern portion. I'm currently sitting in a hotel after having spent the afternoon at the International Antarctic Centre in Christchurch as we fly out tomorrow.

We went to Timaru first for a family wedding, and then took off from Christchurch in the Camper and headed straight away for Hanmer Springs. From there we wandered up the east coast via Kaikoura to Blenheim then Havelock (absolute gem of a little town), Takaka/Pohara, back to Kaikoura, and then out to Akaroa. This time around we only had nine days to travel due to said wedding.

We really enjoyed the Marlborough Sounds region, and the Takaka Hill was an experience all of its own. https://www.dangerousroads.org/austra...

A storm had washed away significant sections of the road in places, so we had to wait at traffic lights allowing cars in one direction only. Mind you, we'd had plenty of practice at that during the Kaikoura sections.

Next trip - North Island! Might have to take you up on your offer to catch up we when pop over again. It's lovely to catch up with Goodreads friends :)


message 24: by Ian (new)

Ian Miller | 11768 comments Leonie, enjoy the rest of your vacation here anyway. It seems you struck the more troublesome parts to visit. If you can remember the road coming to Kaikoura and remember where the sea was, just to let you know the sea used to be right up to the banks on the side of the road. I gather the shore has lifted significantly and the sea is further away.


message 25: by Leonie (new)

Leonie (leonierogers) | 1579 comments Ian wrote: "Leonie, enjoy the rest of your vacation here anyway. It seems you struck the more troublesome parts to visit. If you can remember the road coming to Kaikoura and remember where the sea was, just to..."

It's really quite amazing. I took quite a few photos of various slips. You can see where the seabed has lifted - apparently a couple of metres, and the South Island is now five metres closer to the North Island.

I'll see if I can post some photos. Nope, whatever photobucket is doing, it isn't working. 😡


message 26: by Ian (new)

Ian Miller | 11768 comments Somewhat interestingly, I used to go there and collect seaweed for analyses for scientific papers, where you have to specify exactly where you found it. Those places are now seemingly significantly away from salt water!

If you ever post those photos somewhere, I would be interested in knowing where.


message 27: by Leonie (new)

Leonie (leonierogers) | 1579 comments I'll probably pop some up on my blog in the next week or two. I've only got a couple that show the seabed, but a few show how much higher the road is now.

I have a variety of photos of various slips and the methods used to hold them back.


message 28: by Ian (new)

Ian Miller | 11768 comments Your blog is where? (I am interested to see the photos :-) )


message 29: by Holly (new)

Holly (goldikova) My father in law lives on the big island of Hawaii; so far his house has been spared; but the lava flow is only a couple of miles away. That would be so bizarre, having a river of molten rock nearby.


message 30: by Leonie (new)

Leonie (leonierogers) | 1579 comments Ian wrote: "Your blog is where? (I am interested to see the photos :-) )"

Here you go. I thought I had some better photos than I actually took, but you can see a bit.

https://leonierogers.me/2018/08/30/th...


message 31: by Ian (new)

Ian Miller | 11768 comments Leonie, the two coastal pics are good. I more or less recognise the places (I have previously driven down there many times going to Christchurch) and so I can see the land has come up a bit. Of course the tides make a difference too :-)


message 32: by Philip (new)

Philip (phenweb) | 3078 comments All this talk of volcanoes and earthquakes. I have just been to Sorrento and had the opportunity to climb up Vesuvius as well as visit the leftovers of Pompeii and Herculaneum destroyed in 79AD. Naples and surrounding cities (3m population) now sit beneath waiting for the next eruption. 1944 leaving a trail of cooled magma.
The view from the top is spectacular. Odd sulfur cloud emitting just to let you know its sleeping not dead.




message 33: by Leonie (new)

Leonie (leonierogers) | 1579 comments I find it fascinating that people live so comfortably in such close proximity to what is in effect an inevitable event.


message 34: by Ian (new)

Ian Miller | 11768 comments Leonie wrote: "I find it fascinating that people live so comfortably in such close proximity to what is in effect an inevitable event."

Yes, the town of Taupo has quite expensive real estate, but it is essentially in the caldera of a super volcano. The concept seems to be that eruptions come in cycles - a group of about 2,000 yr intervals, each getting bigger, then nothing for about 35,000 yrs, or so I was once told by one of the people who studied it. The last eruption was over 1900 yrs go, and was midway between an intermediate and the most powerful. Real estate is expensive. I am happy to go there for a vacation (because you should get some warning rumbles before it blows) but I assure you I did get nervous there once when there was a swarm of earthquakes.

Auckland is another interesting city - it is on a volcanic field but what is odd is that no volcano there erupts twice - just that a new one pops up somewhere. It should give insurance companies nightmares.


message 35: by Leonie (new)

Leonie (leonierogers) | 1579 comments It'd be like insurance company lottery, or insurance company Russian roulette.


message 36: by Scout (new)

Scout (goodreadscomscout) | 6151 comments I'm amazed that people continue to live on the fault line in California and shrug off a little tremor. They should look at what happened in 1906.


message 37: by Ian (new)

Ian Miller | 11768 comments Scout, since I live right beside a fault line, I guess I can comment. You don't think about it. You just try to find a place that looks sound, and hope (a) a really big one doesn't happen while you are alive (and I have been through a few in the high 6 low 7 scale and am all right) and (b) if it does, you have some sort of preparation. As far as NZ goes, there is no place that is really safe. I used to think Christchurch was as safe was any place here, and look what happened a few years ago - fault lines nobody even knew existed.


message 38: by Scout (new)

Scout (goodreadscomscout) | 6151 comments Do you think living in such a place affects your perspective at all as regards the future, mortality? Isn't it always in the back of your mind that the earth might shift?


message 39: by Michel (new)

Michel Poulin Scout wrote: "Do you think living in such a place affects your perspective at all as regards the future, mortality? Isn't it always in the back of your mind that the earth might shift?"

That would be a good question to ask to the Japanese, whose country litterally sit atop a multitude of fractures and joints. Maybe some of our readers who are either Japanese or live in Japan could add something to this discussion.


message 40: by Philip (new)

Philip (phenweb) | 3078 comments Had the discussion with the Vinyard owner I visited outside Naples in the Red Zone from Vesuvius. They have frequent tremors as well as the eruption risk.

Ian summed it up you just live with it or take a calculated risk. If you don't like it you move.


message 41: by Leonie (new)

Leonie (leonierogers) | 1579 comments Philip wrote: "Had the discussion with the Vinyard owner I visited outside Naples in the Red Zone from Vesuvius. They have frequent tremors as well as the eruption risk.

Ian summed it up you just live with it o..."


Some would be unable to move - due to economic circumstances and geography, I would think.


message 42: by Nik (new)

Nik Krasno | 16032 comments Some people are just guided but the assumption 'it's gonna be alright' even in the face of the obvious peril -:)
Like Philip enjoyed visiting Pompeii some years ago. Didn't climb Vesuvius, but went for Etna on Sicily on a different occasion


message 43: by Ian (new)

Ian Miller | 11768 comments As for moving, the question is, where to? In NZ you would have to leave the country to be really safe, although the top of Northland is probably safe. A decade ago, Christchurch would have been considered safe and look what happened there - undiscovered faults shifted. Another point is, if your house is well-built and on good ground, a quake is a severe inconvenience, but it is not the end of the world. Christchurch had almost world-record accelerations from its quake, thanks to wave interference effects, but now it is back to being a normal city, although with a lot of building projects. It is a mix of "hope it won't happen to me" and "there aren't really a lot of options".


message 44: by Rita (new)

Rita Chapman | 153 comments I experienced a small earthquake in Spain many years ago and Australia occasionally has tremors. Does anyone take earthquakes into consideration when planning their vacation? (unless it's to NZ of course!)


message 45: by Ian (new)

Ian Miller | 11768 comments My guess is no. Certainly not me. I have been to California (LA and SF) several times and assumed all would be well. Also a number of other places. You have to be rather unlucky to spend a week or so only in a place and have it disrupted. However, how about the question in another way - weather. Do you avoid places in the season for, say, typhoons, cyclones, hurricanes, whatever you want to call them. I do. These can be just as hazardous, if not more so.


message 46: by Scout (new)

Scout (goodreadscomscout) | 6151 comments Well, with hurricanes, you can see what's coming and prepare or leave. The scariest thing about earthquakes is that there's no warning and no escape. Ian, you say that it's not a big deal "if your house is well-built and on good ground," but how do you know what is good ground? And, no matter how well-built, your home rests on the ground.


message 47: by Scout (new)

Scout (goodreadscomscout) | 6151 comments I'd like to ask my question again: Do you think living in such a place affects your perspective at all as regards the future, mortality? Isn't it always in the back of your mind that the earth might shift?


message 48: by Ian (new)

Ian Miller | 11768 comments Scout, if you live in an earthquake zone, you start to take a real interest in what is underneath. Will it liquefy? Will it slip? There were some houses around Sumner (a Chch suburb) that were on really steep parts of the peninsula, but nothing serious happened to them because they were on basalt. There were the odd ones that were built far too close to the edge of a cliff (for the spectacular view) that found ground falling away from them, but again, because it was basalt, the whole lot did not, merely what had fractured, so although the houses were ruined, people could escape out the front doors. (front as defined as towards the road.) In NZ you can get a geological statement on your ground.


message 49: by Ian (new)

Ian Miller | 11768 comments Scout, it is not always at the back of my mind - you would get unnecessarily depressed if that were the case. Since I live on a steep hillside, though, I do take some interest every now and again as to what is happening just downhill from my place. Oddly enough, I have never lost section from an earthquake, but some has slipped away during horrible floods. The answer is, as usual, plant trees with good root systems but not too much weight up top.


message 50: by Scout (new)

Scout (goodreadscomscout) | 6151 comments Okay, Ian. I get it that you're okay living with the possibility of an earthquake. You're betting on it not swallowing you whole, which would be my worst scenario. I'm probably making too much of this, since I have no experience with earthquakes.


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