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)


Kuril Islands to

Cuba to

Eastern Turkey to

Southern California to

Banda Sea to

Molucca   to


Outer shadow zone edge (141-148 degrees)


Kuril Islands to Coquimbo, Chile, 

Cuba to Maldive Islands, Taal Volcano, Philippines, New Guinea, Mindanao, Molucca, Halmahera, 

Eastern Turkey to  Chile Rise, New Zealand, Fiji, Kermadec Is, Tonga, Samoa, 

Molucca to Argentina, Central Chile, Honduras, 

Southern California to

Banda Sea to Canary Islands, Costa Rica, Chile, 


Node 3 (120 degrees)


Kuril Islands to Ecuador, 

Cuba to Bonin Islands, Mariana Islands,, Solomon Islands, Xizang, China,  

Eastern Turkey to Hawaii, Galapagos, Solomon Islands, Central Chile, Peru,  

Molucca to Morocco,

Southern California to South Sandwich Islands, 

Halmahera to South Sandwich Islands, Western Texas, 


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


Kuril Islands to Costa Rica, Cuba, Puerto Rico,

Cuba to Iran-Turkey border, Siberia, Tonga, Fiji, Kuril Islands, Iran-Iraq, Eastern Turkey, Central Africa, 

Eastern Turkey to Los Angeles, California, Mammoth Lakes, Central California, Bismarck Sea, Colombia, Barstow, Southern, Central  California, 

Molucca to Northern California, Nunavut, Canada, South of Africa, British Columbia, Oregon, Bosnia, Crete, Albania, Baffin Bay, Central, Northern California, South Africa, Greece, 

Southern California to Drake Passage, Dodecanese Islands,  Hindu Kush, Papua New Guinea, Molucca, Iran, Gansu, Xinjiang, China, Central Turkey, Luzon, Mindanao, Seram, Papua New Guinea, East of Australia, Azerbaijan, Crete, Turkey, Hindu Kush, Taiwan, Northern Territory, Australia, Yunnan, Northern Philippines, Assam, India, Snares, South Island, New Zealand, Crete, Iraq, Halmahera, Tajikistan, Iran, Hindu Kush, Molucca Sea, Philippines, Northern Australia, Papua, New Guinea, Pacific-Antarctic Ridge, 

Halmahera to Nunavut, Canada, Oregon, Bosnia, Crete, Albania, Coast of Oregon, Washington State, Central California, 


Node 4 (90 degrees)


Kuril Islands to New Zealand, Libya, Guerrero, Mexico,

Cuba to Western Turkey,  Dodecanese Islands, Greece,  Kamchatka, 

Eastern Turkey to Newfoundland, Sumbawa, Montana, British Columbia, Puerto Rico, 

Molucca to

Southern California to Libya, Kermadedc, Loyalty Is., Vanuatu, New Britain, 

Halmahera to


Node 5 (72 degrees)


Kuril Islands to Southern Iran, Baja, California, Eastern Turkey, 

Cuba to Libya, Arctic Ocean, Hawaii, northern Alaska, 

Eastern Turkey to  Taiwan, Hokkaido, Japan, northern Alaska, South Indian Ocean, Sumatra, Luzon, Philippines, 

Molucca to

Southern California to Tonga,

Halmahera to


Node 6 (60 degrees)


Kuril Islands to Hudson Bay, Coast of Northern California, 

Cuba to Chile Rise, Gulf of Alaska, Iceland, Araucania, Chile, 

Eastern Turkey to Flores, Nunavit, Canada, Northeast China, 

Molucca to Macquarie Is.,  New Zealand,

Southern California to East Pacific Rise, Iceland, Jan Mayen, 

Halmahera to  Macquarie Is.,


Node 7 (52 degrees)


Kuril Islands to China, Hawaii, Seram, Indonesia, New Britain, Vancouver, British Columbia, Canada,

Cuba to Central Chile, Vancouver, British Columbia, Canada,

Eastern Turkey to Mayotte, Myanmar, Azores, Severnaya Zemlya, 

Molucca to

Southern California to

Halmahera to South Island, New Zealand,