This came across my social media feed:

USGS Earthquakes since 1973

U.S. Geological Earthquakes Survey
1973 - 4,539 Earthquakes
1974 — 4,528 Earthquakes
2000 — 19,131 Earthquakes
2010 — 23,040 Earthquakes
2011 — 22,392 Earthquakes
2013 — 89,622 Earthquakes
2014 — 118,404 Earthquakes
2015 — Over 36,000 Earthquakes...

One pastor gave this some context:

Earthquakes on the rise, USGS stats confirm. Jesus predicted 2000 yrs ago, "And GREAT EARTHquakes shall be in divers places, and famines, and pestilences; and FEARFUL sights and great signs shall there be from HEAVEN." (Luke 21:11) Christians, signs BELOW being fulfilled...now watch for signs from ABOVE!

The data seems to be a little selective, and I assume earthquake detection instruments have increased in both number and sensitivity since 1973.

Are earthquakes numbers increasing significantly and consistently since 1973?

  • 12
    Note that there is no such thing as the "US Geological Earthquakes Survey". May 15 '15 at 9:02
  • 10
    Note, this question has nothing to do with religion.
    – Sklivvz
    May 15 '15 at 11:27
  • 1
    @sweeneyro, it should probably be read with an implicit "so far" for 2015 (it's not over yet, remember). If this was published in March, it surely would support the "is on the rise" statement.
    – Zano
    May 15 '15 at 14:50
  • 11
    The quote from the pastor should be removed, as it doesn't add anything to this question. It could possibly be a separate question, such as "Is the increase of earthquakes a sign of the end times?" but I kind of doubt it would be on-topic here. May 15 '15 at 15:24
  • 2
    Why are you quoting a pastor in regards to a geology topic?
    – DA01
    May 15 '15 at 22:09

The title of this 2011 paper pretty much answers the question by itself: Global risk of big earthquakes has not recently increased.

(For the record: Peter M. Shearer and Philip B. Stark, doi: 10.1073/pnas.1118525109 PNAS January 17, 2012 vol. 109 no. 3 717-721)

They noted that there had been an increase in large earthquakes in 2004-2011, and some other apparent clustering, and looked back over the data since 1900 to see if there was sufficient statistical evidence to suggest that large earthquakes were occurring more frequently, or whether it could just be explained by chance.

Our conclusion that the global threat of large earthquakes has not recently increased is based both on the lack of statistical evidence that regionally declustered seismicity is temporally heterogeneous on a global scale and on the implausibility of physical mechanisms proposed to explain global clustering. [...] The recent elevated rate of large earthquakes has increased estimates of large earthquake danger: The empirical rate of such events is higher than before. However, there is no evidence that the rate of the underlying process has changed. In other words, there is no evidence that the risk has changed, but our estimates of the risk have changed.

While this focussed on large (Magnitude 7 and above) earthquakes, rather than all measured earthquakes, like the source infographic did, I think this is appropriate because (a) it lowers any effect caused by sampling error reduced as more numerous and more sensitive equipment is produced and (b) magnitude 1 and 2 tremors aren't what people are thinking when they hear the word 'earthquake'.

  • 4
    The OP is specifically asking about US earthquake stats, though. Those are increasing, simply due to heavy increases in Fracking and other mining practices. (I would make this an answer but I'm at work) May 15 '15 at 8:02
  • 8
    @TheForestAndTheTrees I don't think you can infer that the question is about the US. The source image refers to the "US Geological Earthquakes Survey" but there is no such thing. There is an organization called the US Geological Survey (USGS), who measure earthquakes worldwide. They presumably release data about the number of earthquakes in the US and also worldwide so it's not at all clear what the data in the source image refers to. May 15 '15 at 9:02
  • 3
    @TheForestAndTheTrees that's a bold claim and you should prove it.
    – edc65
    May 15 '15 at 12:50
  • 4
    I'm sorry, but I have to agree that this is a poor response. There is a well-known increase in low magnitude earthquakes, likely due to fracking. For example, I'll cite the USGS. I think that these are much more relevant to the question than large, magnitude 7+ earthquakes. After all, the original image was always talking about thousands of earthquakes per year, but there are only tens of mag 7+ earthquakes per year source.
    – KAI
    May 15 '15 at 13:51
  • 4
    @DVK I'm using "might" is the conservative way that scientists use it. In other words, in the sense that it takes a while for things to be settled. There are a number of studies which state that wastewater wells and earthquakes are linked. For example, this one from Science magazine. However, since this is an ongoing topic of research, I am willing to admit the possibility that the conclusions from such studies are incorrect, although I think it unlikely.
    – KAI
    May 15 '15 at 16:13

I cannot confirm the numbers in the original image, although some of the recent numbers appear to be roughly consistent with USGS numbers.

However, the general point seems to be correct: the number of earthquakes has been increasing per year. But, the pastor is not correct: the number of "great" earthquakes is not increasing (see the response by Oddthinking). That is, the number of small earthquakes has been increasing by a large factor in some areas, almost certainly due to humans (wastewater injection wells from fracking, etc), while the number of large earthquakes has not.

For example, this USGS site shows that the rate of earthquakes from much of the US was roughly constant until the year 2000, but has been rapidly increasing since then.

enter image description here

This study from Oklahoma, a hotbed of fracking, concludes:

The seismicity rate in 2013 was 70 times greater than the background seismicity rate observed in Oklahoma prior to 2008. While unlikely, this rate could have been potentially explained by natural variations in earthquake rates from naturally occurring swarms. The seismicity rate is now about 600 times greater than the background seismicity rate, and is very unlikely the result of a natural process.

I'm not exactly clear on how these large, local increases in earthquakes would change the global number of earthquakes, but it should make the original claim plausible.

  • 4
    That graph is in very odd units. Why plot cumulative number of earthquakes rather than earthquakes/year?
    – reirab
    May 15 '15 at 17:39
  • 2
    @reirab I would guess two reasons: To imply "we don't have data before this date" instead of "number of earthquakes were the same before this date" without having to state it, and so that the spike at the end is more pronounced than it would have been with earthquakes per year (like right around where 2013 would be, the rise drops off for a short period)
    – Izkata
    May 15 '15 at 20:32

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