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Earthquake Predictions
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The Caribbean Region is newly defined for these predictions and now (as of 02-02-08) includes only the NE sector within ≈400 km* radius from Mayagüez, Puerto Rico, on the west coast at latitude 18.20° and longitude -67.14°. The western arc of this region passes through Santiago in the Dominican Republic and extends in the east to include the Virgin Islands. The region covers most of the seismic activity directly affecting the Virgin Islands, Puerto Rico, and two-thirds of the Dominican Republic.
*The radius is 400 km plus an ≈10% error margin of about 40 km to include close events.
This new definition represents a 75% reduction in the region as previously defined (previously it was defined as including all areas within an 800 km radius of a point centered on Lat 15° N and Lon 66° W in the Caribbean Sea) and allows for greater focus and relevance of earthquake predictions for the eastern Caribbean. Sometimes it will be possible to give special reports or predictions for other Caribbean locations, say for regions around Barbados and Trinidad, but from now on most earthquake predictions will be for the region as defined above, unless specifically stated as being otherwise.
All earthquake predictions for the Caribbean Region are for the largest earthquake in a nominated 10-day period, plus an error margin of about one day, but no attempt is made to make forecasts for all periods because of the constraints of private research. Each table, with its original earthquake prediction, will remain subject to revisions or updates for 10 days.
Why updates may be necessary... because earthquakes interact in a very dynamic system. Just as in reporting the weather, the latest information must be taken into account to improve forecasting.
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SCROLL DOWN FOR TABLES
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STATISTICS FOR EARTHQUAKE PREDICTION For period 13 August 2007 - 12 July 2008 (256 predictions)
SUCCESS RATES*
Mag Observed Events Predicted Events
(How many predicted?) (How many observed?)
Pred. Obs. %Correct Obs. Pred. %Correct
<M4 60 67 = 90% 58 66 = 88%
M4.0-4.9 76 85 = 89% 57 60 = 95%
M5.0-5.9 73 77 = 95% 90 96 = 94%
M6.0+ 25 27 = 93% 29 34 = 85%
___________________________________________ *These statistics are updated bi-monthly and refer to tabled predictions only, as no attempt
is made to predict all large earthquakes worldwide. Note that currently successful predictions are those which are ≈80% accurate on magnitude, and within a 10-day time window (plus an error margin of about one day), reflecting the fact that earthquake prediction is still an imprecise science. However, research here is aimed at improving this margin and currently 75% of all magnitude predictions have an error margin of only 15%. Any apparent numerical discrepancies between the two halves of the above table are due to the error margins: for example, an M6 category predicted quake might have come in at M5.8
OVERALL success rate from 256 predictions worldwide-
Observed events that were predicted (234/256) = 91.4%
Predicted events that were observed (234/256) = 91.4%
SCIENTIFIC: Correlation of Predicted & Observed Magnitudes
There is a highly significant correlation (r=0.90, P< .0001) between the full set of observed and predicted magnitudes, including 'false alarms' (Worldwide N=256 as of 12 July 2008).
EARTHQUAKE PREDICTION TABLES
M= Earthquake magnitude. See HOME page for further explanation of table entries.
Earthquake Location Maps - see the USGS web site for maps of earthquakes in these tables.
New 3-layer Table Format & Prediction Rules (25 Nov 07)
Please read following points to fully explain tables below:
1. The Original Earthquake Prediction, and details relating to it, are given in the top light blue layer of each table.
The 'expected date' (or dates) given here provide the best current estimate of when the largest earthquake event is most likely within the nominated 10-day window (date prediction made +10, or possibly ≈11 days). Please note that the time window now includes an error margin of ≈1 day which may extend it to include some closely predicted events, reflecting the fact that earthquake prediction is an imprecise science. The above estimates and other details may be updated, if necessary, in the next section of the table.
The Expected Range in Magnitude, for each event after 14th July 2008, is given as the predicted magnitude +/-1 magnitude (previously it was given as +/-0.5M). Statistical analyses of over 100 of the latest predictions show that 95% of them can be expected to fall within +/-1M of the predicted values, regardless of the region of the world involved. From 14th July 2008, any predictions which fall outside these limits by as little as 0.1M will be regarded as unsuccessful.
2. Revisions, if required, are given in the mid blue layer of each table, and these revisions are used in the final assessments of the results. Please see the statement above explaining why updates are desirable, and note that revisions are limited to a 10-day window. Revisions usually relate to
earthquake magnitude and expected timing, but may also include location.
3. The Observed Earthquake and details (for the event we were attempting to predict) are given in the bottom dark blue layer of each table. The event recorded here is the largest earthquake for the nominated 10-11 day period. 'PENDING...' simply means that the anticipated event has not yet happened, or that we are waiting for the event to be posted on the web site.
CARIBBEAN - Puerto Rico Region
See also Long-term Forecasts
No. 9
PREDICTED M4.5 Expected Date/Location Original prediction 20 Apr '08 20-30 Apr (UTC) '08 Predicted at 0223 hrs UTC (time window open to 30 April, plus ≈1 day margin) Probability of event >90% within ≈400 km of Western Puerto Rico
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REVISION nil |
| OBSERVED M4.0 Observed Date/Location Magnitude accuracy 88.9% 20 April at 10:27:33 hrs, Lat 19.679° Lon 68.901° Predicted 8 hours ahead 171 km NE of Santo Domingo Dominican Republic |
No. 8
PREDICTED M4.6 Expected Date/Location Original prediction 8 Apr '08 8-14 Apr (UTC) '08 Predicted at 0032 hrs UTC (time window open to 18 April, plus ≈1 day margin) Probability of event >85% within ≈400 km of Western Puerto Rico
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REVISED to M3.8 Expected Dates Revised at 0750 hrs on 16 April 16-18 April |
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OBSERVED M4.0 Observed Date/Location
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No. 7
PREDICTED M4.3 Expected Date/Location Original prediction 24 Mar '08 24-26 Mar (UTC) '08 Predicted at 0319 hrs UTC (time window open to 3 Apr, plus ≈1 day margin) Probability of event >85% within ≈400 km of Western Puerto Rico
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REVISED to M3.6 Expected Dates Revised at 0348 hrs on 3 April 3 April, plus ≈1 day margin
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OBSERVED M3.3 Observed Date/Location
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No. 6
PREDICTED M4.3 Expected Date/Location Original prediction 9 Mar '08 9-11 Mar (UTC) '08 Predicted at 0344 hrs UTC (window open 10 days to19 Mar+1 day margin) Probability of event >90%
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REVISED to M3.5 Expected Dates Revised at 0138 hrs on 19 March 19-20 March Upgraded range M3.0-4.4 |
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OBSERVED M3.4 Observed Date /Location Magnitude accuracy 97.1 % 19 March, Lat 19.29° Lon -65.98°, 0603 hrs Predicted 0425 hrs ahead 91 km N of San Juan, PR
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No. 5
PREDICTED M3.8 Expected Date/Location Original prediction 23 Feb '08 23 Feb-4 Mar (UTC) '08 Predicted at 2321 hrs UTC (time window open 10 days to 4 Mar) Probability of event >95% within 400 km of Mayagüez, PR
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REVISION nil
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OBSERVED M4.3 Observed Date/Location Magnitude accuracy 88.4% 3 March, . Lat 19.478° Lon -70.339° Predicted 9 days ahead 375 km WNW of Mayagüez, PR 116 km NNW of Santo Domingo, Dominican Republic
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No. 4
PREDICTED M4.6 Expected Date/Location Original prediction 4 Feb '08 4-7 Feb (UTC) '08 Predicted at 0230 hrs UTC (time window open 10 days to 14 Feb) Probability of event >90% Puerto Rico Region or Mona Passage? |
REVISIONS nil
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OBSERVED M5.2 Observed Date/Location Magnitude accuracy 88.5% 4 February, Lat 19.00°N Lon 66.86°W Predicted 5 hours ahead 95 km NW from San Juan Puerto Rico Region |
No. 3
PREDICTED M4.8 Expected Date/Location Original prediction 24 Jan '08 24-29 January (UTC) '08 Predicted at 0423 hrs UTC (time window open 10 days to 2 Feb) Probability of event >90% Puerto Rico Region? |
REVIEWS nil
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OBSERVED M4.2 Observed Date/Location Magnitude accuracy 87.5% 29 January at Lat 19.81, Lon -68.92 Predicted 5 days ahead 182 km NE from Santo Domingo Dominican Republic
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No. 2
PREDICTED M4.9 Expected Date/Location Original prediction 10 Jan '08 10-20 January (UTC) '08 Predicted at 0355 hrs UTC (time window open 10 days to 20 Jan) Magnitude Range M4.4-M5.4 |
REVISED to M4.2 Expected Date/Location Updated range M3.8-M4.6 13-20 January Revised at 0817hrs on 13 January
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OBSERVED M4.1 Observed Date/Location Magnitude accuracy 97.6% 16 January Lat 17.76, Lon -67.97 Predicted 3 days ahead 210 km WSW San Juan, PR PUERTO RICO REGION
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No. 1
PREDICTED M5.8 Expected Date/Location Original prediction 16 Dec '07 16-20 December (UTC) '07 Predicted at 0945 hrs UTC (time window remains open 10 days to 26 Dec) Probability of event >90% |
REVISION nil
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OBSERVED M5.4 Observed Date/Location
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