The number of large earthquakes this month

Hi,everyone,

I notice that there were only two large earthquakes happened.One happened in Indonesia(2021-06-03 M6.1), the other happened in Kermadec Islands(2021-06-20 M6.5).This month’s earthquake frequency is at a low level.

Usually, there are about 10 earthquakes of magnitude 6 or above in a month. Of course, most of them are earthquakes of magnitude 6.

So,my question is will this increase the risk of large earthquakes around the world?If so, how will the influence degree be? Will the last week of June become dangerous?

The following is my statistics of the number of earthquakes with magnitude 6 and above per month in the first half of the year:
January(12),February(16),March (20),April (14),May(13)June(2?)

Thank you for your attention to this topic and look forward to your reply.

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Hi Wilson,
Thank you for your interest.
The number of earthquake of magnitude >= 6.0 is variable from one month to another, even though one can expect tenth of eathquake in the this range of magnitude per month, it could be less. For example I checked our DB in June 2018, there were only 4 earthquakes of magnitude >=6.0. And on top of that, the month is not over yet :wink:
It is impossible to predict what’s going to happen by the end of the month or the rest of the year, or even if one can expect a larger one. We cannot predict an earthquake.
I hope it help,
best regards,

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Thank you for your warm reply jul,it is helpful.
Recently, I’m sorting out the number of earthquakes in recent years and making it into a table. It should be completed soon. The number of earthquakes of M6, M7 and ≥ M8 has an unclear rule in a certain period of time, which will be more obvious in the table.
I will send out the form after I finish it. I’m look forward to communicating with you again.
Best wishes

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Look forward to the table, but not sure that the magnitude bands are actually relevant (they are arbitrary?). Maybe a scatter plot of magnitude against time would reveal a more significant categorisation / banding, or possibly a smooth spectrum with no gaps? In addition to magnitude, I think there may be patterns in location of the quakes too, concentrated on southwest-Pacific / west Indonesia, west coast South America, Caribbean etc, but I haven’t formulated any rules for this yet - it is just qualitative. The more exploration of the data the better I would say! Rgds Dave

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Thank you for your sincere reply,DAC,

I admit that the statistics of earthquake magnitude are vague, because to tell you the truth, I don’t know what to look for. I just set a time limit, such as one year, and then count the number of earthquakes, but it’s unknown what the number is related to. But it shows some regularity.

These statistics are attractive, including the scatter plot you mentioned and so on. I saw a video about the statistics of the East Japan earthquake data in 2011. The author took the longitude line as the abscissa and the focal depth as the ordinate. He counted the earthquakes within one year after the main earthquake and made a chart. The dense points on the chart (each point is an earthquake) formed a beautiful arc, like a logarithmic function of a > 0, It clearly shows the subduction of the Pacific plate into the North American plate off the coast of East Japan.

I think this is wise. We can’t see the earth’s interior with naked eyes, but we can reconstruct it with data. After all, the information comes from the earth’s interior, It is the “voice” of the earth.

I have finished my chart. I want to do more analysis, but my ability and time are limited. I will send the chart below. I hope you can enjoy it and find something new.

best regards

Hi,everyone,I looked up the USGS database and made quantitative statistics,now I’ve finished my chart. I hope you like it.

The first is the quantity chart. The abscissa is the year, and the ordinate is the number. I have separately counted the number of earthquakes of M6, M7 and ≥ M8 in each year, which is a total of three charts. There is also a total plot (≥ M6).




Then there is the frequency chart. My method is to divide the number of days by the number of times (366 days or 365 days / times). For example, the frequency of M6 in 2001 is equal to 3, which means that there will be an M6 earthquake every three days in 2001. Of course, this is a statement of probability, not once every three days.And so on, the M7 frequency of 2011 is equal to 26.1, meaning that the M7 earthquake occurs once a month (26.1 days) this year.

Therefore, the higher the vertical scale value in the chart, the better. Because in probability, it means that the interval between two large earthquakes is long, in reality, it means that the number of large earthquakes in this year is less.




The above is my chart, I hope you like it and have a good time!
Yours sincerely

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Hi Wilson,
That’s a nice piece of work, congrats
cheers,

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Here’s the chart for the month of the year,enjoy!





















Thank you , jul, that’s very kind of you to say so!