Pre-Shift Adjustments

Where Domino quakes, one plate pushing another, became evident in 1999, by 2002 pre-shift adjustments in compression around the Pacific Rim and tearing of the African Rift were evident. Searching the CNSS Earthquake Catalog for quakes 5.0 Richter or greater for the 2 week period preceeding the 7.9 Alaskan quake on Nov 3, 2002, we find there is an almost instant reaction, within the same day, for deep quakes on one side of a plate to push to a strong surface quake on the other side of the plate or abutting plate. Compression around the Pacific Rim and tearing of the African Rift were the focus of this activity, plate adjustments expected during the shift itself.

Offered by Nancy.

Date     Location      No. Lat.     Long.     Depth   Mag.
10/22/02 Fiji           1  -20.4610 -178.5720 551.60  6.20
10/23/02 Alaska         2   63.5760 -148.0880  14.00  6.70

Deep quake in Fiji [southern edge of Pacific Plate] followed by strong quake in Alaska
[northern edge of Pacific Plate]

10/23/02 New Zealand    3  -30.6780 -179.8210 360.50  5.00
10/24/02 Zaire          4   -1.8990   28.9040  11.00  6.20

Deep quake in New Zealand [eastern edge of Indio/Australian Plate] followed by strong 
surface quake in Zaire [rift point in African Plate] 

10/25/02 Iwo Jima       5   30.6010  130.0160 119.10  5.30
10/30/02 Fiji           6  -17.4870 -174.3500  86.50  5.30   
10/31/02 New Guinea     7   -3.4200  148.4740  33.00  6.10

Deep quakes in Iwo Jima [eastern edge of Euroasian Plate] and Fiji [western edge of 
Pacific Plate] followed by strong surface quake in New Guinea [northern edge of 
Indio/Australian Plate abutting both]

11/01/02 Solomon Is     8  -19.6430  169.2820 400.00  5.10
11/02/02 Sumatra        9    3.0240   96.1810  33.00  7.50

Deep quake in Solomon Is [western edge of Pacific Plate] followed by strong quake 
in Sumatra [edge of abutting Indio/Australian Plate] 

11/02/02 Indonesia      10  -7.1490  128.8550  82.20  5.30
11/02/02 Sumatra        11   2.9540   96.4230  33.00  6.20
11/03/02 Iwo Jima       12  38.8760  141.9170  49.30  6.10
11/03/02 Alaska         13  63.5200 -147.5300   5.00  7.90

Deep quake in New Guinea [center of southern lob of Euroasian Plate] followed by 
strong surface quakes in Sumatra [abutting Indio/Australian Plate border], then 
Iwo Jima [abutting western edge of Pacific Plate] then Alaska [upper edge of Pacific Plate]