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General Category => World News => Topic started by: mystery-ak on September 19, 2017, 07:04:53 pm

Title: Powerful 7.1 earthquake strikes Mexico City
Post by: mystery-ak on September 19, 2017, 07:04:53 pm
Associated Press

A powerful earthquake jolted Mexico City on Tuesday, causing buildings to sway sickeningly on the anniversary of a 1985 quake that did major damage to the capital.

The extent of damage and injuries was not immediately clear, but people fled office buildings along the central Reforma Avenue.

The U.S. Geological Survey calculated its preliminary magnitude at 7.1. Mexico's seismological agency set the magnitude at 6.8 and said its center was east of the city in the state of Puebla.

Pictures fell from walls and objects were shaken off of flat surfaces. Some people dove for cover under desks.

more
http://www.latimes.com/world/la-fg-mexico-earthquake-20170919-story.html
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: TomSea on September 19, 2017, 08:02:41 pm
That should mean significant damage from the little I am hearing.

(http://www.excelsior.com.mx/media/pictures/2017/09/19/1755981.jpg)(http://www.excelsior.com.mx/media/pictures/2017/09/19/1756030.jpg)(http://www.excelsior.com.mx/media/pictures/2017/09/19/1756035.jpg)

http://www.excelsior.com.mx/comunidad/2017/09/19/1189372#imagen-11
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: DB on September 19, 2017, 11:36:58 pm
Rough day in Mexico...

Our turn in California is coming...
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: Mom MD on September 20, 2017, 12:00:18 am
Death toll is already 100 we need to pray for these poor people
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: TomSea on September 20, 2017, 01:05:08 am
131, a whole building collapsed, apartments, offices, however. Mexico City has been built on a fault line or something like that.
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: DB on September 20, 2017, 01:56:00 am
131, a whole building collapsed, apartments, offices, however. Mexico City has been built on a fault line or something like that.

Much of Mexico city is built on dry lake bed and is prone to liquefaction when shaken. Liquefaction means the seemingly solid surface the buildings are built on starts to behave like a liquid where foundations can sink/move like it was built on mud when they otherwise wouldn't.
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: TomSea on September 20, 2017, 02:20:14 am
Much of Mexico city is built on dry lake bed and is prone to liquefaction when shaken. Liquefaction means the seemingly solid surface the buildings are built on starts to behave like a liquid where foundations can sink/move like it was built on mud when they otherwise wouldn't.

You know your stuff, that's right. And the Torre Latinoamericana was built to deal with that but you probably know that already. The article talks about how it was built. I heard it has a "floating foundation" if that is accurate to say.

https://en.wikipedia.org/wiki/Torre_Latinoamericana



Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: DB on September 20, 2017, 05:43:25 am
There something pretty strange about this earthquake I've never seen before.

It has been more than 11 hours since the earthquake and there's not a single aftershock on the earthquake map. Not one.

https://earthquake.usgs.gov/earthquakes/map/#%7B%22autoUpdate%22%3A%5B%22autoUpdate%22%5D%2C%22basemap%22%3A%22street%22%2C%22feed%22%3A%227day_all%22%2C%22listFormat%22%3A%22default%22%2C%22mapposition%22%3A%5B%5B3.8204080831949407%2C-119.267578125%5D%2C%5B29.726222319395504%2C-76.2890625%5D%5D%2C%22overlays%22%3A%5B%22plates%22%2C%22faults%22%5D%2C%22restrictListToMap%22%3A%5B%22restrictListToMap%22%5D%2C%22search%22%3Anull%2C%22sort%22%3A%22newest%22%2C%22timezone%22%3A%22utc%22%2C%22viewModes%22%3A%5B%22map%22%2C%22settings%22%5D%2C%22timeZone%22%3A%22local%22%2C%22searches%22%3A%5B%5D%2C%22event%22%3A%22us2000ar20%22%7D (https://earthquake.usgs.gov/earthquakes/map/#%7B%22autoUpdate%22%3A%5B%22autoUpdate%22%5D%2C%22basemap%22%3A%22street%22%2C%22feed%22%3A%227day_all%22%2C%22listFormat%22%3A%22default%22%2C%22mapposition%22%3A%5B%5B3.8204080831949407%2C-119.267578125%5D%2C%5B29.726222319395504%2C-76.2890625%5D%5D%2C%22overlays%22%3A%5B%22plates%22%2C%22faults%22%5D%2C%22restrictListToMap%22%3A%5B%22restrictListToMap%22%5D%2C%22search%22%3Anull%2C%22sort%22%3A%22newest%22%2C%22timezone%22%3A%22utc%22%2C%22viewModes%22%3A%5B%22map%22%2C%22settings%22%5D%2C%22timeZone%22%3A%22local%22%2C%22searches%22%3A%5B%5D%2C%22event%22%3A%22us2000ar20%22%7D)
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: mountaineer on September 20, 2017, 11:03:41 am
There something pretty strange about this earthquake I've never seen before.

It has been more than 11 hours since the earthquake and there's not a single aftershock on the earthquake map. Not one.
That is an interesting phenomenon.  :pondering:

Death toll now over 240.
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: Gefn on September 20, 2017, 11:21:15 am
That is an interesting phenomenon.  :pondering:

Death toll now over 240.

Hurricanes and earthquakes this month. Mother Nature is grumpy. I've read some volcanoes are starting to stir too.
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: Gefn on September 20, 2017, 11:34:18 am
Oh there was a6.1 earthquake last night in New Zealand, according to my earthquake app.
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: thackney on September 20, 2017, 11:57:46 am
You know your stuff, that's right. And the Torre Latinoamericana was built to deal with that but you probably know that already. The article talks about how it was built. I heard it has a "floating foundation" if that is accurate to say.

https://en.wikipedia.org/wiki/Torre_Latinoamericana

No, it is a pile foundation over 100 ft deep (33 meters).  It reaches past the clay soil expected to liquefy under earthquake type events to a more stable level below.

http://www.iitk.ac.in/nicee/wcee/article/8_vol5_363.pdf
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: mountaineer on September 20, 2017, 03:21:10 pm
Mexico earthquake: Death toll rises, rescue attempts continue
Nicole Chavez, associate writer CNN Digital


Rescuers in hard hats and masks descended Wednesday on Mexico City in search of survivors after a deadly earthquake struck the region.

"The priority now is continue rescuing those who are still trapped and provide medical attention to the injured," President Enrique Peña Nieto said, calling the quake -- the second to shake Mexico in 12 days -- "a new national emergency."

The 7.1 magnitude quake turned dozens of buildings in central Mexico into dust and debris, killing at least 225 people.

According to Luis Felipe Puente, national coordinator of civil protection for the Interior Ministry, 94 of the deaths came in Mexico City -- which, with an urban area of more than 21 million people, is one of the most populous cities in the Western Hemisphere.
There were also 71 deaths in Morelos state, 43 in Puebla state, 12 in the state of Mexico, four in Guerrero state and one in Oaxaca state, according to Puente's tally.  ...  More at CNN (http://www.cnn.com/2017/09/20/americas/mexico-earthquake-rescues/index.html)
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: DB on September 21, 2017, 08:24:08 am
There still hasn't been a single aftershock shown on the USGS earthquake map since the 7.1 struck!

Either it is a miracle allowing people to dig others out without aftershocks further collapsing buildings or the USGS map is broken...

I have never seen a major earthquake like that have no aftershocks. The earthquake further down the west coast that was an 8.1 a couple of weeks ago still has many aftershocks being reported on the map.
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: TomSea on September 21, 2017, 08:29:09 am
Then, Japan had an earthquake too; 6.1

http://www.foxnews.com/world/2017/09/20/magnitude-6-1-earthquake-strikes-off-coast-japan.html
Quote

KAMAISHI, Japan –  The U.S. Geological Survey says a magnitude-6.1 earthquake has hit off the coast of Japan.

The agency's website says the temblor hit early Thursday about 283 kilometers (176 miles) southeast of the city of Kamaishi and more than 322 kilometers (200 miles) east of Fukushima.
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: thackney on September 21, 2017, 12:49:12 pm
There still hasn't been a single aftershock shown on the USGS earthquake map since the 7.1 struck!

Either it is a miracle allowing people to dig others out without aftershocks further collapsing buildings or the USGS map is broken...

I have never seen a major earthquake like that have no aftershocks. The earthquake further down the west coast that was an 8.1 a couple of weeks ago still has many aftershocks being reported on the map.

For comparison purposes:

Following the 1964 Good Friday 9.2 in Alaska:

Quote
In the first day there were 11 aftershocks with magnitude greater than 6.0; in the next three weeks there were 9 more. Residents endured thousands of aftershocks in the months following the quake, and felt smaller aftershocks for more than a year.

https://archive.usgs.gov/archive/sites/www.usgs.gov/newsroom/article.asp-ID=106.html
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: DB on September 22, 2017, 10:52:19 am
For comparison purposes:

Following the 1964 Good Friday 9.2 in Alaska:

https://archive.usgs.gov/archive/sites/www.usgs.gov/newsroom/article.asp-ID=106.html

And another day goes by with ZERO aftershocks shown on the USGS map. In all the news I've seen from Mexico city I haven't heard anyone say anything about aftershocks hampering rescue efforts.

I find that very, very odd.
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: GtHawk on September 22, 2017, 03:24:06 pm
And another day goes by with ZERO aftershocks shown on the USGS map. In all the news I've seen from Mexico city I haven't heard anyone say anything about aftershocks hampering rescue efforts.

I find that very, very odd.
According to theguardian:More than 11 aftershocks have been registered, with the strongest reaching magnitude 4.

https://www.theguardian.com/world/live/2017/sep/20/mexico-city-earthquake-dozens-dead-powerful-quake-live-updates
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: DB on September 22, 2017, 09:37:58 pm
According to theguardian:More than 11 aftershocks have been registered, with the strongest reaching magnitude 4.

https://www.theguardian.com/world/live/2017/sep/20/mexico-city-earthquake-dozens-dead-powerful-quake-live-updates


Thank you!

So apparently the USGS system to detect them is broken because their online map still shows no aftershocks anywhere near the initial 7.1.
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: XenaLee on September 22, 2017, 10:02:51 pm
There something pretty strange about this earthquake I've never seen before.

It has been more than 11 hours since the earthquake and there's not a single aftershock on the earthquake map. Not one.

https://earthquake.usgs.gov/earthquakes/map/#%7B%22autoUpdate%22%3A%5B%22autoUpdate%22%5D%2C%22basemap%22%3A%22street%22%2C%22feed%22%3A%227day_all%22%2C%22listFormat%22%3A%22default%22%2C%22mapposition%22%3A%5B%5B3.8204080831949407%2C-119.267578125%5D%2C%5B29.726222319395504%2C-76.2890625%5D%5D%2C%22overlays%22%3A%5B%22plates%22%2C%22faults%22%5D%2C%22restrictListToMap%22%3A%5B%22restrictListToMap%22%5D%2C%22search%22%3Anull%2C%22sort%22%3A%22newest%22%2C%22timezone%22%3A%22utc%22%2C%22viewModes%22%3A%5B%22map%22%2C%22settings%22%5D%2C%22timeZone%22%3A%22local%22%2C%22searches%22%3A%5B%5D%2C%22event%22%3A%22us2000ar20%22%7D (https://earthquake.usgs.gov/earthquakes/map/#%7B%22autoUpdate%22%3A%5B%22autoUpdate%22%5D%2C%22basemap%22%3A%22street%22%2C%22feed%22%3A%227day_all%22%2C%22listFormat%22%3A%22default%22%2C%22mapposition%22%3A%5B%5B3.8204080831949407%2C-119.267578125%5D%2C%5B29.726222319395504%2C-76.2890625%5D%5D%2C%22overlays%22%3A%5B%22plates%22%2C%22faults%22%5D%2C%22restrictListToMap%22%3A%5B%22restrictListToMap%22%5D%2C%22search%22%3Anull%2C%22sort%22%3A%22newest%22%2C%22timezone%22%3A%22utc%22%2C%22viewModes%22%3A%5B%22map%22%2C%22settings%22%5D%2C%22timeZone%22%3A%22local%22%2C%22searches%22%3A%5B%5D%2C%22event%22%3A%22us2000ar20%22%7D)

When you realize that there are small earthquakes going on every other day in certain areas.... it makes you glad you don't live in or around any of those certain areas. 

I like this website for current earthquake stats & info.

https://earthquaketrack.com/
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: TomSea on September 23, 2017, 04:51:41 pm
Quote
Earthquakes
3 hours ago
Strong new magnitude 6.1 earthquake rocks jittery Mexico

A 6.1-magnitude earthquake struck southern Mexico on Saturday, the third to jolt the reeling nation this month.

The strong quake was centered about 11 miles south-southeast of Matias Romero in the state of Oaxaca, which was the region most battered by a magnitude 8.1 quake on Sept. 7.

There was no immediate reports of deaths or injuries.

Continued: http://www.foxnews.com/world/2017/09/23/strong-new-magnitude-6-1-earthquake-rocks-jittery-mexico.html

So, this was another quake earlier today in the South of the country.
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: TomSea on September 23, 2017, 04:53:38 pm
When you realize that there are small earthquakes going on every other day in certain areas.... it makes you glad you don't live in or around any of those certain areas. 

I like this website for current earthquake stats & info.

https://earthquaketrack.com/

Good website, a minor quake in Idaho, quite a few other temblors in Mexico in the south of the country.
Title: Re: Powerful 7.1 earthquake strikes Mexico City
Post by: DB on September 23, 2017, 09:03:27 pm
According to theguardian:More than 11 aftershocks have been registered, with the strongest reaching magnitude 4.

https://www.theguardian.com/world/live/2017/sep/20/mexico-city-earthquake-dozens-dead-powerful-quake-live-updates


I wonder if they are counting the aftershocks of the original 8.1 quake? The 6.1 today was in the area of the original quake. Still nothing on the map located anywhere near the 7.1 quake that did all the damage to Mexico City.