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Last 48 hours in Kathmandu – a Mathematician's analysis of the earthquakes

28 pointsby anaxag0rasabout 10 years ago

3 comments

stevewilhelmabout 10 years ago
USGS Aftershock Forecast for the Magnitude 7.8 Nepal earthquake of April 25, 2015<p>(as of April 26, 2015) In the coming week, USGS expects 3-14 M≥5 aftershocks of the magnitude 7.8 Nepal earthquake. Additionally, USGS estimates that there is a 54% chance of a M≥6 aftershock, and a 7% chance of a M≥7 aftershock during this one-week period. After this, in the following month and then the following year, USGS expects several M≥5 aftershocks, with a significant chance of M≥6 aftershock (greater than 50%). The potential for an aftershock larger than the mainshock remains, but is small (1-2% in each time period).<p>Felt earthquakes (i.e., those with M≥ 3 or 4) will be common over the next weeks to months. Based on general earthquake statistics, the expected number of M≥ 3 or 4 aftershocks can be estimated by multiplying the expected number of M&gt;=5 aftershocks by 100 or 10, respectively. The expected location of the aftershocks will be in the zone of current activity and at its edges. Currently aftershocks are occurring in a zone extending approximately 200 km away from the mainshock epicenter.<p>This information is preliminary and subject to change.<p>from <a href="http:&#x2F;&#x2F;earthquake.usgs.gov&#x2F;earthquakes&#x2F;eventpage&#x2F;us20002926#general_summary" rel="nofollow">http:&#x2F;&#x2F;earthquake.usgs.gov&#x2F;earthquakes&#x2F;eventpage&#x2F;us20002926#...</a>
jjwisemanabout 10 years ago
This is not a great analysis, and is kind of confusing.<p><pre><code> Things will improve, the law of math promises it. </code></pre> Ah well, if a mathematician says the law of math promises it!<p>See Omori&#x27;s law (and Båth&#x27;s Law and the Gutenberg–Richter law), and the roughly 5% chance that this quake was a foreshock for an even bigger quake (&quot;the 2002 Sumatra earthquake is regarded as a foreshock of the 2004 Indian Ocean earthquake with a delay of more than two years between the two events&quot;)
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lostloginabout 10 years ago
The magnitude isn&#x27;t everything, Christchurch NZ being a case in point. It&#x27;s later, shallow earthquake caused much more destruction and killed many, while the bad initial quake killed no one directly. I&#x27;m no expert, but the magnitude of the quake is relative to the depth in a way that masks the actual destructive power.