Statistical evidence indicates that some triggering or promotion forward in time can occur in regions which are under high stress due to additional stress events of  small size. Among these are surface and body waves passing through a region. Triggering may be dynamic with the promoted earthquake occurring at the same time as the stress event or delayed with an earthquake occurring later in time but still related to the stress event through water lubrication or other various geophysical effects on the faults. We have argued in this report for the past 35 years that this effect is most observable where the seismic waves are largest. In general this occurs at distances from the rupture ends of  the earthquake producing those waves (mainshock) which we have termed nodal distances. These are defined by the formula D=360*m/n where D is the distance in degrees and m<=m where n an m are small integers. These are also the locations of  the maximum corrections to magnitude in the standard Jeffreys-Bullen tables. In addition there is focusing of  seismic energy from reflections and refractions of f the core-mantle and the inner-outer core boundary of  the earth. This focuses energy at the surface in the distance between 101 and 108 degrees (core-mantle) and 141-148 degrees (inner-outer core boundary). In this report we monitor seismicity at these distances following major earthquakes as experience has shown that strong and/or unusual earthquake are much more likely to occur at these distance from the mainshock.


Antipodal (~180 degrees)


Bouvet Island to Rat Islands, Andreanof Islands,

Rat Islands to Bouvet Island,

Komandorsky Is. to

Eastern Mexico to

Near Islands to


Outer shadow zone edge (141-148 degrees)


Bouvet Island to Coast of No. California, Hawaii, Montana, Washington, Vancouver, Idaho, Oregon, Northern California, Nevada, Hokkaido, Japan, 

Rat Islands to

Eastern Mexico to Andaman Is, Kerguelen Islands, Java, Sumba, Ceram, Flores, Myanmar, South of Australia, 

Komandorsky Is. to

Guatemala to East, West Indian Ridge, Western Australia, Minahasa, East Timor, India, Celebes,

Near Islands to


Node 3 (120 degrees)


Bouvet Island to Quebec, New York, New Hampshire, Northern Reykjanes Ridge, western Mexico, 

Rat Islands to Northern Chile,

Eastern Mexico to Tajikistan, Eastern New Guinea, Taiwan, Papua New Guinea, Congo, Bismarck Sea,

Komandorsky Is. to Uganda, Northern Chile, Southern Peru, 

Near Islands to Southern East Pacific,   Northern Chile, Southern Peru,


P- and S- shadow zone edge and node 7 (101-110 degrees)


Bouvet Island to Tonga, Fiji, Celebes, Hindu Kush, Fiji, Tonga, Chiapas, Nicaragua, El Salvador, Caucasus, South East Pacific Rise, Banda Sea, 

Rat Islands to Ecuador, North Atlantic,

Eastern Mexico to  Sea of Japan, Guam, East of Honshu, Japan, Snares Island, N.Z, Northern Mariana Is. Caucasus, Bonin Islands, Guam, Honshu, Cook Strait, New Zealand, Auckland Is, Izu Is, Japan, Vanuatu, Honshu, Japan, Hokkaido, Western Turkey, southern New Zealand, 

Komandorsky Is. to Macquarie Islands, Auckland Islands, Colombia, Central Atlantic Ocean, Ecuador, Barbados, 

Guatemala to Solomon Islands, Southern Mid-Atlantic, Vanuatu, Greece/Turkey,  Crete, Cook Strait, Loyalty Is, Hokkaido, Kurils, New Zealand, Honshu, Japan, Vanuatu, Western Turkey, Loyalty Islands, Crete, Southern Kurils,  

Near Islands to Ecuador, Peru,  


Node 4 (90 degrees)


Bouvet Island to Sumatra, Iran, Venezuela, South of Java, Crete, Northern Colombia, Bali,

Rat Islands to South of Sumatra, Eastern Mediterranean, Crete, 

Eastern Mexico to Poland, South of Fiji, Tonga, South Sandwich Islands, Italy, Kurils, Kermadec Islands,

Komandorsky Is. to Tunisia, Costa Rica, Puerto Rico,

Near Islands to Dominican Republic, Puerto Rico, Haiti,


Node 5 (72 degrees)


Bouvet Island to Central Peru,

Rat Islands to Ceram, Tonga, Jalisco, Mexico,

Eastern Mexico to Central Mid-Atlantic, Iceland, Rat Is, Andreanof Is, Chukotka, Russia,

Komandorsky Is. to Nova Scotia, Alabama, Tonga, Michoacan, Mexico, Tennessee, Reykjanes Ridge, Pennsylvania, Georgia, Vanuatu, Banda Sea, Fiji/Tonga, Nova Scotia, Tennessee, Georgia,  

Near Islands to Georgia, Caucasus, Banda Sea, Vanuatu, Ohio, Iraq, Guerrero, Mexico,


Node 6 (60 degrees)


Bouvet Island to Central Chile

Rat Islands to Oklahoma

Eastern Mexico to northern Chile, Fox Islands, Alaska, Central Chile, Hawaii, Alaska, Reykjanes Ridge,

Komandorsky Is. to Admiralty Is, Iceland, New Mexico, Bismarck Sea, Mindanao, New Britain, New Guinea, Kansas, Eastern Canada, Iceland, Myanmar, China, Oklahoma, New Britain, 

Near Islands to New Ireland, New Guinea, Oklahoma,


Node 7 (52 degrees)


Bouvet Island to

Rat Islands to Taiwan

Eastern Mexico to Antofagasta, western Canada, Central Chile, Coquimbo,

Komandorsky Is. to Idaho, Greenland Sea, North of New Guinea, Sichuan, China, Taiwan, Yellowstone, Central California, Nevada,

Near Islands to Southern California,


Node 8 (45 degrees)


Bouvet Island to

Rat Islands to Central California

Eastern Mexico to

Komandorsky Is. to Taiwan,  Coast of Northern California,

Near Islands to Hawaii, Northern California, Taiwan,