
Nepal earthquake, magnitude 7.3, strikes near Everest - illuminek
http://www.bbc.com/news/world-asia-32701385
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chrisra
A magnitude 7.8 earthquake is 2.511 times bigger than a magnitude 7.4
earthquake on a seismogram, but is 3.981 times stronger (energy release).

via
[http://earthquake.usgs.gov/learn/topics/calculator.php](http://earthquake.usgs.gov/learn/topics/calculator.php)

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illuminek
I did not quite understand "3.981 times stronger (energy release)", but god
bless everyone.

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Swizec
The Richter scale is exponential. According to chrisra a 7.8 earthquake
release almost 4x the energy of a 7.4 quake.

I didn't run the numbers, but it seems plausible the difference would be that
big.

According to Wikipedia[1] a 7.5 quake releases 11 petajoules of energy, while
a 7.8 quake release 32 petajoules.

[1]
[http://en.wikipedia.org/wiki/Richter_magnitude_scale#Example...](http://en.wikipedia.org/wiki/Richter_magnitude_scale#Examples)

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nixy
This is something that's always bothered me. The Richter scale is not, for
normal people like myself, a good earthquake magnitude indicator. I always
have trouble grasping that 7.5 and 7.8 are so far apart in terms of severity
since my mind is set to find a .3 difference negligible. I would like to have
a metric measurement of earthquakes that would allow me to more quickly
understand the scale and size of a quake.

Edit: The difference between a 8.6 one and a 8.7 one is huge. The difference
is as big as the difference between 0.0 and 8.35, in megatons at least.

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NZ_Matt
The richter scale in general is not a good indicator of the destructiveness of
an earthquake. You need to consider the location of the epicenter and the
depth of the quake before coming to any sort of conclusion.

I experienced this first hand here in Christchurch, NZ. We had a 7.1M quake
and then a 6.3M aftershock 6 months later. Despite being almost an entire
magnitude smaller the 6.3M aftershock was 10x more destructive. This was
primarily because the epicenter of the 6.3M quake was 40km closer to the city
and some unusually high verticle accelerations caused by the strike slip
motion of the fault and the local geography.

[http://en.wikipedia.org/wiki/2010_Canterbury_earthquake](http://en.wikipedia.org/wiki/2010_Canterbury_earthquake)

[http://en.wikipedia.org/wiki/2011_Christchurch_earthquake](http://en.wikipedia.org/wiki/2011_Christchurch_earthquake)

The Mercalli Intensity Scale was developed to give a better indicator of the
actual effect to people on the ground.

[http://en.wikipedia.org/wiki/Mercalli_intensity_scale](http://en.wikipedia.org/wiki/Mercalli_intensity_scale)

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eliaspro
Please help the OSM HOT [1] team to map the regions struck by the earthquake.
Without proper/up-to-date maps, coordinating emergency efforts is hardly
possible.

[1]
[http://wiki.openstreetmap.org/wiki/2015_Nepal_earthquake](http://wiki.openstreetmap.org/wiki/2015_Nepal_earthquake)

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legulere
Please get used to how OSM works before starting to map. There has been lots
of bad data added by new people to OSM in Nepal recently. Cleaning up may be
more work than adding new.

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samikc
Writing this from Kolkata (India). We were asked to evacuate the office
building, as it was shaking. Just got an all clear to get back in.

God bless everyone.

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dschiptsov
That could be quite bad, because vast majority of houses in the area of Namche
Bazaar has been built without steel-and-concrete reinforcement - just stones
and cement, due to lack of motorable roads in Sulukhumbu region to supply
steel and other building materials.

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nabaraz
Can't believe another earthquake has hit Nepal and it's even worse. Please
pray for the people of Nepal and donate. A little can make all the difference.

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illuminek
Aftershocks felt, there were at least 2. I ll call them major ones. I was
sitting on 4th floor. It felt very strong.

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spacefight
Yes, 5.6 and 6.3 after 7.4.

Source: [https://twitter.com/USGSBigQuakes](https://twitter.com/USGSBigQuakes)

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frabcus
Lots of Nepal Earthquake datasets (including map of new quake) on the
Humanitarian Data Exchange:

[https://data.hdx.rwlabs.org/nepal-
earthquake](https://data.hdx.rwlabs.org/nepal-earthquake)

