link to Home Page

icon Increasing

USGS updated one quake recently, which is here, from their database:

Date       Time         Lat      Lon     Depth Mag Magt Nst 
2001/06/23 20:33:14.13 -16.2650 -73.6410 33.00 8.40 Me  518

Due to it, all my values jerked strongly upwards. They became so significant, that I had to bring it to your attention.

catalog=CNSS
start_time=1990/01/01,00:00:00
end_time=2001/08/15,20:16:31
minimum_magnitude=5.5
maximum_magnitude=10
minimum_depth=0
maximum_depth=70
event_type=E

Now, the analysis.

N = count,
E**2 is my old pwr property, X_n always indicates average, where X is name
E = 10 ** mag
m_max is new and shows the strongest event for that year.

year     N       E**2/G  E**2_n/G          E/k   E_n/k    m_n  m_max
1990:  286      1078448 /    3771      243680 /    852   5.93  7.40
1991:  242       815370 /    3369      237267 /    980   5.99  7.20
1992:  322      2802484 /    8703      378968 /   1177   6.07  7.50
1993:  280      1320784 /    4717      335934 /   1200   6.08  7.10
1994:  332     17969639 /   54125      513444 /   1547   6.19  8.10
1995:  404     35508634 /   87893      961635 /   2380   6.38  8.00
1996:  412     43992506 /  106778      929913 /   2257   6.35  8.20
1997:  346     11004743 /   31806      569957 /   1647   6.22  7.80
1998:  289     20770312 /   71870      551891 /   1910   6.28  8.10
1999:  337      9364165 /   27787      601623 /   1785   6.25  7.70
2000:  380     29052484 /   76454      812284 /   2138   6.33  8.00
2001:  154     72232249 /  469041      663005 /   4305   6.63  8.40

Last 2 years value percentages (2001 value / 2000 value - 1) * 100%:

N: -59.5% of quakes of previous year so far, detailing:

E**2 figure: +148.6% / +513.5% average
E figure: -18.4% / +101.4% average
Average magnitudes of later year have changed +4.804%

Latest event which made it to these figures:
2001/08/13 20:11:22.55, a 6.40 mag. quake

Well, wow! +500% average increase and +100% average increase, although I would not talk about the E**2 that is built specifically to show strong events very clearly. As the E**2 is really not any physical property, I think it would probably be best to ignore it, despite it's very juicy. However, I do think that the E value I computed is at least in the correct direction. The /k or /G indicates scale, not unit. Energy would presumably be in Joules. k is for 1_000, G for 1_000_000_000 multiplication. The data shows a 100% increase for average strength of events so far. Before the update on 2001/06/23, it used to be more modestly some 30 % high, but this of course changes the stage significantly. I have also another idea which would be to plot a 3-dimensional graph showing quakes assorted by magnitude and year. So, it would be a plane where the height is the count, x is the year, and y is the magnitude range, 5.5, 5.5 to 6.0, 6.0 to 6.5, etc. I think it would also give important insight, and hopefully show the trend over years as well, without being hard to comprehend (from what I see, the trend is blindingly obvious and very alarming).

Offered by Antti.

icon