Chile Forum

I understand that basically the entire country is in a seismic zone, but still wonder if there are any parts of Chile that are less likely to be hit by an earthquake, or at least areas where an earthquake would claim less fatalities. I've never experienced such phenomena and the Wikipedia entry on Arica scared me a bit:

The earthquake of August 13, 1868 struck near the city with an estimated magnitude of 8.0 to 9.0, killing an estimated 25,000 to 70,000 people.[5] Others estimate that the population of Arica was less than 3,000 people and the death toll was around 300.[citation needed] It produced a tsunami recorded in Hawaii, Japan and New Zealand. Arica lies very close to the subduction zone known as the Peru-Chile Trench where the Nazca plate dives beneath the South American plate, threatening the city with megathrust earthquakes. In the worst-case scenario, a similar earthquake today of at least 8 or higher would likely kill tens of thousands of people and cause serious damage to parts of the city. Entire streets would be crushed. Thousands of buildings and bridges would topple. Liquefaction would rupture gas mains, water pipes, and vital communication systems. Tsunamis generated by the quake would claim thousands more lives and wash kilometers inland, washing away more buildings and bridges, and launching boats, cars, trucks, chunks of debris, and other objects inland. By the time it ends, the devastation would be incredible. Aftershocks and fires would hamper rescue operations, hundreds of thousands would be killed or injured, and tens of billions of dollars worth of property would be destroyed.

pajaritoblanco wrote:I understand that basically the entire country is in a seismic zone, but still wonder if there are any parts of Chile that are less likely to be hit by an earthquake, or at least areas where an earthquake would claim less fatalities. I've never experienced such phenomena and the Wikipedia entry on Arica scared me a bit:

The earthquake of August 13, 1868 struck near the city with an estimated magnitude of 8.0 to 9.0, killing an estimated 25,000 to 70,000 people.[5] Others estimate that the population of Arica was less than 3,000 people and the death toll was around 300.[citation needed] It produced a tsunami recorded in Hawaii, Japan and New Zealand. Arica lies very close to the subduction zone known as the Peru-Chile Trench where the Nazca plate dives beneath the South American plate, threatening the city with megathrust earthquakes. In the worst-case scenario, a similar earthquake today of at least 8 or higher would likely kill tens of thousands of people and cause serious damage to parts of the city. Entire streets would be crushed. Thousands of buildings and bridges would topple. Liquefaction would rupture gas mains, water pipes, and vital communication systems. Tsunamis generated by the quake would claim thousands more lives and wash kilometers inland, washing away more buildings and bridges, and launching boats, cars, trucks, chunks of debris, and other objects inland. By the time it ends, the devastation would be incredible. Aftershocks and fires would hamper rescue operations, hundreds of thousands would be killed or injured, and tens of billions of dollars worth of property would be destroyed.

In the XII Región we have comparatively fewer and less severe earthquakes. Not completely free of earthquakes, though.

The far south as Px says, but hey the whole world has earthquakes these days ask the US eastern seaboard.

The red lines on the map mark the boundaries of tectonic plates. The line along the Chilean coast is a subduction zone - the plate to the west is being pushed down underneath the South American plate. The zone between these two plates is the place where the majority of earthquakes happen. As you can see, it runs the length of Chile, hence heaps of earthquakes. It's also the reason there be volcanoes here.

Why is Px's country estate different? Not certain, but I can guess... See the wiggly red line on the LHS of the picture heading southeast and running into the subduction zone? This would appear to mark a "spreading centre" or "divergent margin" - both sides of this plate boundary are moving apart. When this zone runs into the subduction zone, the direction of relative plate movement will be different, plus there is another plate involved to the southeast (between the red lines).

The different plate movement directions (oblique versus direction collision) means energy transfer and release (earthquakes) will be different in both areas.

Are you asleep yet?

If you're still awake and want to know a little more, google "Nazca plate" - you'll find more than enough pretty pictures to keep you occupied...

Worlds quickest conversation killer : "So, what do you do?" "I'm a geologist." "Oh..."

pajaritoblanco
...the Wikipedia entry on Arica scared me a bit:

no worries - you can just live in a yurt - on high ground?
but, having experienced a mere wannabe terremoto (6.5) in arica in 2010...
g~j couldn't resist sharing this old favorite...

http://www.youtube.com/watch?v=1FgOJzQqT1E

now, that said...
we will share with any/all interested..
a really cool, real-time earthquake freeware program...
http://www.wolton.net/quake.html
download this sucker...
play with it...
have fun!

EARTHQUAKE 3D

WATCH EARTHQUAKES IN 3D... Zoom and spin your way around the globe while viewing earthquakes in three dimensions! Control how the Earthquakes and Earth are shown. See at a glance up to seven days of global earthquake activity with this desktop Earthquake monitor.

ANIMATE AND CONTROL... Adjust and customize the display to see earthquakes in a variety of different ways. Filter earthquakes by size and time – then select from many display options that include quake indicators and map references. Earthquakes are shown in near real-time using the latest data from the USGS via the internet.

Earthquake 3D is FREE! Download it and use it NOW! No complicated setup or installation. Just unzip it and it's ready to go.

Great program, g-j! I'll be up all night investigating.
Is this what Dutchsinse uses, I wonder?

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The last decent earthquake(s) near a populated area here in Magallanes was 1949-50, where the original was measured as about a 7.5 and located near Cabo Froward at the southernmost point on the continent. There were 6 killed and 18 injured, along with quite a bit of structural damage. There were significant aftershocks for a couple of months, with some landslides reported in Tierra del Fuego. One of those aftershocks resulted in the death of three people but I think that was in Tierra del Fuego and not on the continent.

There's an interesting side to that earthquake. In the early 1940s, Chile sent out its first earthquake-oriented building standards, effective for every region of the country. In Punta Arenas there was considerable grousing, esp from architects, because nobody here could remember an earthquake in the region. After some years of mostly local moaning, a group of architects sent a letter to the national government building standards agency, asking that Magallanes be exempted from the earthquake standards and declared a no-earthquake zone. They had impeccable timing. They sent that letter about one week before the 7.5 earthquake that seriously damaged Punta Arenas. The local legend has it that their letter was never answered.

Thanks guys. I just can't come to terms with the idea of one day being surprised by an earthquake, and I would be absolutely powerless, unable to protect myself and my family. You can confront a mugger or a beast, and even in the case of a flood or fire you have some time to pick up your children and a bundle. But what can you do when streets are wiped off in the twinkling of an eye?

At the moment, I am trying to choose a region. Besides many other factors I have to consider earthquakes too. So far I was attracted to the area between Santiago and Puerto Montt, the Región de los Lagos being my favourite, but now I am going to examine the extreme South as well.

....

I've just come across this post by patagoniax in another thread:

Within Chile, you may wish to consider Puerto Varas. On inland lake and thus exempt from tsunami.

Does this mean exempt from earthquakes too?

pajaritoblanco wrote:I've just come across this post by patagoniax in another thread:

Within Chile, you may wish to consider Puerto Varas. On inland lake and thus exempt from tsunami.

Does this mean exempt from earthquakes too?

No exemptions. Remember that the quakes that cause tsunamis can occur thousands of miles away.

You want Chile, you take earthquake risk. That includes Pto Varas and that region.

Image: Pto Montt 1960 earthquake

The majority of human deaths in earthquakes come from building colaps. So, if you don't want to die in an earth quake live in a tent in the middle of a field away from any steep slopes and the coast.