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Earthquake Predictions
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THE NEW ZEALAND REGION is subdivided for earthquake forecasts as follows:
(1) The North Island Region - within ≈400 km radius* of Taupo at Lat -38.687° and Lon 176.07° includes the Nelson region and top of the South Island. This region has experienced 17 strong earthquakes (M6.0-M6.8) and two major ones (both M7.1) since the beginning of 1975. (USGS/NEIC and Google Earth sources).
(2) Christchurch - "Southern Region"- within ≈500 km radius* of Christchurch, at Lat -43.527 and Lon 172.622. This region, which necessarily overlaps** with the above North Island Region (up to 250 km NW of Wellington), takes into account some very important interactions between earthquakes which should improve the accuracy of future forecasts, especially for large events like the recent M7.1 earthquake on Sept 3 (UTC), 2010. Since 1975 this region has experienced 18 strong earthquakes (M6.0-M6.8) and 4 major M7.0-M7.8 earthquakes.
(USGS/NEIC and Google Earth sources).
(3) Invercargill - Lower South Island Region ≈380 km radius* of Invercargill at Lat -46.41 168.36. This region also overlaps** extensively with the above Christchurch Region because of interactions between earthquake events. Since 1975 this region has experienced 10 strong earthquakes (M6.0-M6.8) and 5 major M7.0-M7.8 earthquakes.
*The radius of each of the above regions is 400 km, 500 km, and 380 km respectively, plus a ≈10% error margin of about 38-50 km in order to include events that may occur close to the nominated regional boundary
**The New Zealand zones (as elsewhere in the world) are overlapping zones because interactions between earthquakes in the region make it impossible to have discrete zones for forecasting earthquakes. Thus, for those living in the overlapping areas, the largest quake that is forecast in each of the respective overlapping zones should be considered as potentially relevant..
When an earthquake prediction is made the relevant tables below
will clearly label which region is involved. Because there are three regions, two tables may be running concurrently and readers may
need to scoll down through the top three tables to check for all current ones.
All earthquake predictions for the New Zealand Region are for the largest earthquake in the nominated 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
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 periodically 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.
NEW ZEALAND REGIONS
Two-three tables may be running concurrently,
so please scroll down.
See also Long-term Forecasts
These Long-term Forecasts now give the approximate timing of the largest regional earthquakes for the lunar month ahead.
The Short-term tables below will be used to make revisable and, generally, more precise earthquake predictions for some of the important events that are indicated as being imminent in the Long-term Forecasts.
No. 23 New Zealand - Northern Region
PREDICTED M4.8 Expected Date/Location Original prediction 1st August 1-6 August (UTC) 2009 Predicted at 0252 hrs UTC Probability of event >90% within approx. 500 km of Rotorua
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OBSERVED M4.3 Observed Date/Location |
Previous tables have been deleted to save space