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)


Ecuador to Sumatra, Andaman Is, 

Kermadec Islands to Morocco, 

Tajikistan to

Central Turkey to

Molucca Sea to

Banda Sea, Indonesia to

Northern California to South Indian Ocean, 

Fiji to Morocco, 

Michoacan, Mexico to

New Guinea to Central Mid-Atlantic,


Outer shadow zone edge (141-148 degrees)


Ecuador to

Kermadec Islands to Iceland, Iran, Iraq, Northern Mid-Atlantic, 

Tajikistan to Central Peru, northern Chile,  

Central Turkey to North Island, New Zealand, Fiji, West Chile Rise, South Island, Cook Strait, New Zealand,  Tonga/Fiji/Samoa, East Pacific Rise,

Molucca Sea to  Costa Rica, Nicaragua, Northern Mid-Atlantic, Tarapaca, Chile, Central Chile, Costa Rica, Nicaragua, Argentina, Cape Verde, 

Banda Sea to Ecuador,  Nicaragua, Tarapaca, Chile, Costa Rica, South Carolina, Panama, Gulf of Maine, Indonesia to Canary Islands, Guatemala, northern Chile, Argentina, Nicaragua, Chile, Maine,    

Northern California to

Fiji to Ukraine, Crimea, Romania, mid-Atlantic, Iran, Lebanon, Iceland, Azores, Turkey,  Mid-Atlantic, Reykjanes Ridge, 

Michoacan, Mexico to Western Australia, Mozambique, Bali, Andaman Is,  Semeru Volcano, Java, Owen Fracture Zone, Sumatra, 

New Guinea to Virgin Islands, Morocco, South Africa, Portugal, Puerto Rico, Dominican Republic, Mid-Atlantic, Azores, northern Atlantic, 


Node 3 (120 degrees)


Ecuador to Solomon Isl,

Kermadec Islands to Quebec, 

Tajikistan to Gulf of California, Taupo, North, South Island, New Zealand, Kermadec Is, 

Central Turkey to Solomon Islands, Atacama, Central Chile, Hawaii, 

Molucca Sea to Gulf of California, Nebraska, South Sandwich Islands, Western Texas, 

Banda Sea, Indonesia to Gabon, Northern Sumatra, Iceland,   

Northern California to Gabon, Northern Sumatra, Java, Red Sea,  

Fiji to Greenland, South Africa, Nunavut, Quebec, Canada, Virgin Islands, Puerto Rico, 

Michoacan, Mexico to Iran-Turkey, Kyrgyzstan, Romania, South of Australia, Tajikistan, Taiwan, 

New Guinea to Albania, Greece, Puerto Rico, Iceland, Missouri, Bosnia, Illinois, Arkansas, Gulf of Mexico, Chiapas, Mexico, Iceland, Los Lagos, Chile,  


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


Ecuador to North Island, Kermadec Is, NZ, Solomon Islands, 

Kermadec Islands to Nebraska, Colombia, Mongolia, Oklahoma, Alberta,  

Tajikistan to Colorado, Vanuatu, California, Oklahoma, Texas, 

Central Turkey to Texas, Honduras, Colombia, Papua New Guinea, Coast of northern California, Western Australia, Central California, Columbia, Texas,

Molucca Sea to Washington State, British Columbia, Malta, Central, southern California,  

Banda Sea, Indonesia to Vancouver, Eastern Mediterranean, Greenland Sea, Coast of Oregon, Vancouver, BC, Western Turkey, 

Northern California to Iran-Iraq, Hindu Kush, Halmahera, Papua, Turkey,  Mindanao, Philippines, Nepal, Minahasa, Molucca Sea, Northern Iran, Banda Sea, South Island, New Zealand, Hindu Kush, Southern Argentina, Bhutan, Mindanao, Tajikistan, Oran, South Islands, New Zealand, Banda Sea, Indonesia, Nepal, Mid-Atlantic Ocean,

Fiji to Mongolia, Northern Peru, South of Panama, Nebraska, Bouvet Island, Alberta, Northern Chile, South of Africa, Arkansas, Oklahoma, Chiapas, Mexico, Algeria,

Michoacan, Mexico to Volcano Islands, Malta, Albania, Turkey, South Island, New Zealand, Mariana Islands, Urals, Pacific-Antarctic Ridge, Kyushu, Japan, Aegean Sea, Mariana Islands, Turkey, Solomon Islands, Southern Honshu, Japan, South Sandwich Islands, Romania, South Island, New Zealand, Lake Baykal, South Atlantic, Mariana Is,  New Ireland, New Britain, Greece, South Island, New Zealand, Mariana Islands,

New Guinea to


Node 4 (90 degrees)


Ecuador to

Kermadec Islands to Andaman Is, Kodiak, Alaska, Oregon, Michoacan, Mexico, Central California, Central Chile, South Sandwich Islands, Alaska Peninsula, Queen Charlotte Islands, Vancouver, 

Tajikistan to Norther mid-Atlantic, Quebec, Molucca Sea, Vancouver, Queen Charlotte Islands,

Central Turkey to Puerto Rico, Vancouver, Queen Charlotte Is, South of Africa, Dominican Republic, Tristan da Cunha, Molucca Sea, British Colombia, Missouri, Aleutians, Alaska,  Buru, Indonesia, Puerto Rico, Montana-British Columbia border, Southeastern US, Southeastern Alaska, Puerto Rico/Dominican Republic, Molucca Sea, Bonin Islands,

Molucca Sea to Turkey, Syria, Tajikistan, 

Banda Sea, Indonesia to Iran- Turkey, Red Sea, Southern Alaska, 

Northern California to Valparaiso, Chile, New Britain, Romania, Taiwan,

Fiji to  Ecuador, Colorado, Oaxaca, Mexico, Sumatra, Queen Charlotte, Vancouver, Texas, Anchorage, Alaska, northern Mexico, South Sandwich Islands, Michoacan, Mexico,  British Columbia, Canada, Guatemala, 

Michoacan, Mexico to South Atlantic, Fiji,

New Guinea to coast of Vancouver, No. California, Oregon, Yukon, Canada, 


Node 5 (72 degrees)


Ecuador to

Kermadec Islands to Izu Islands, Japan,

Tajikistan to Andreanof Is, Banda Sea,

Central Turkey to Mid-Atlantic, Taiwan, Sumatra, Quebec,

Molucca Sea to Fox Islands, 

Banda Sea, Andreanof Is, Indonesia to Tajikistan,

Northern California to Gilbert Islands, 

Fiji to Andreanof Islands, Coast of Hokkaido, Japan, Northern California, Baja California, Fox Islands, Andreanof Islands,

Michoacan, Mexico to  Iceland, Antofagasta, Chile,  

New Guinea to Nepal, Unimak, Fox Islands, Alaska,


Node 6 (60 degrees)


Ecuador to Northern California,

Kermadec Islands to

Tajikistan to Halmahera, Molucca Sea, Sulawesi,  

Central Turkey to Baffin Bay, 

Molucca Sea to Macquarie Island, Tajikistan, Cook Strait, New Zealand, North Island, New Zealand,  Kamchatka, 

Banda Sea, Indonesia to

Northern California to Kuril Is, Iceland, Ecuador,  

Fiji to Sulawesi, Molucca, Minahasa, Easter Island, 

Michoacan, Mexico to Fox Islands, Andreanof Islands, Reykjanes Ridge, Coquimbo, Chile, Fox Islands, Aleutians,  

New Guinea to


Node 7 (52 degrees)


Ecuador to Southern California, 

Kermadec Islands to

Tajikistan to Luzon, Leyte, Philippines

Central Turkey to

Molucca Sea to South Island, New Zealand, Kermadec Islands, 

Banda Sea, Indonesia to  Macquarie Island, Hokkaido, Japan, New Zealand, Tonga, Fiji,

Northern California to Greenland, Puerto Rico, Columbia,

Fiji to Guam, Banda Sea,  Hawaii,

Michoacan, Mexico to East Pacific Rise, Yukon, Northwest Territory, Canada, Kenai, Alaska,  northern Chile, Bolivia, 

New Guinea to Macquarie, Sumatra,