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)


Nevada to

Banda Sea to

Northern Kuril Islands to South Sandwich Islands, 

Kuril Islands to

Cuba to

Eastern Turkey to


Outer shadow zone edge (141-148 degrees)


Nevada to

Banda Sea to Northern Chile,  Central Peru, 

Northern Kuril Islands to Argentina, Southern Mid-Atlantic, Maule, Aisen, Chile, 

Kuril Islands to Southern Mid-Atlantic, Central Mid-Atlantic, Coquimbo, Chile, 

Cuba to South of Australia, Bonin Islands, South Island, New Zealand, Halmahera, Maldive Islands, Taal Volcano, Philippines, New Guinea, Mindanao, Molucca, Halmahera, 

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


Node 3 (120 degrees)


Nevada to

Banda Sea to

Northern Kuril Islands to Chile Rise, 

Kuril Islands to Ecuador, 

Cuba to Xizang, Pakistan, Assam, Hindu Kush, Snares Island, New Zealand, Bonin Islands, Mariana Islands, Solomon Islands, Xizang, China,  

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


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


Nevada to New Zealand, Sichuan, China, Crete, 

Banda Sea to Off Northern California, Sweden, Vancouver, 

Northern Kuril Islands to Mid-Indian Ridge, Kenya, Dominican Republic, Puerto Rico, Northern Mid-Atlantic, 

Kuril Islands to Kenya, Macquarie Islands, Madeira Islands,  Guatemala, Costa Rica, Cuba, Puerto Rico,

Cuba to Kermadec Is. Caucasus, Namibia, Iran-Turkey border, Siberia, Tonga, Fiji, Kuril Islands, Iran-Iraq, Eastern Turkey, Central Africa, 

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


Node 4 (90 degrees)


Nevada to Ryukyu Islands,

Banda Sea to Southern Alaska,

Northern Kuril Islands to Algeria, South, North Island, New Zealand, Chiapas, Oaxaca, Guatemala, 

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

Cuba to Crete, South Sandwich Islands, Western Turkey,  Dodecanese Islands, Greece,  Kamchatka, 

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


Node 5 (72 degrees)


Nevada to

Banda Sea to

Northern Kuril Islands to Ontario, Central East Pacific Rise, Quebec, Oklahoma, Kansas, Bali, Indonesia,

Kuril Islands to Fox Islands, Tonga, James Bay, Canada, Southern Iran, Baja, California, Eastern Turkey, 

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

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


Node 6 (60 degrees)


Nevada to

Banda Sea to

Northern Kuril Islands to Tajikistan, Utah, Southern California, India, Central Indonesia, Mammoth Lakes, California,  

Kuril Islands to India, Java, Sumbawa, Nunavut, Hudson Bay, Coast of Northern California, 

Cuba to Central Mid-Atlantic, SE Alaska, Chile Rise, Gulf of Alaska, Iceland, Araucania, Chile, 

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


Node 7 (52 degrees)


Nevada to

Banda Sea to Macquarie, Kermadec, South Island, New Zealand, 

Northern Kuril Islands to Halmahera Indonesia,

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,