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)


Hawaii to Namibia, South Africa,

Bolivia to Ryukyu Is,

Papua New Guinea to Central, Northern mid-Atlantic, 

Gulf of Alaska to South Indian Ocean


Outer shadow zone edge (141-148 degrees)


Hawaii to Tristan Da Cunha, Southwest Indian Ocean, Mauritius, 

Bolivia to Sea o f Okhotsk, Hokkaido, Xizang, Xinjiang, China, PNG, Sumba, Indonesia, 

Papua New Guinea to Azores, Mid-Atlantic, Bolivia, Haiti, Portugal, Northern Venezuela, Jamaica, Azores, Puerto Rico, Bolivia, Colombia, Virgin Islands, Dominican Republic, 

Gulf of Alaska to Namibia, Mozambique, South Indian Ocean, South Sandwich Islands, 


Node 3 (120 degrees)


Hawaii to Albania, 

Bolivia to So. Iran,

Papua New Guinea to Puebla, Mexico, Albania, Czech Republic, Iceland, South Sandwich Islands, Mediteranean Sea, Missouri, Albania, Oaxaca, Mexico, Oklahoma

Gulf of Alaska to Czech Republic, Ascension Is, Balleny Is, Antarctica,  


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


Hawaii to Myanmar, Java, England, Azores, Sumatra, Nicobar Islands, Czech Republic, Sunda Strait, Tajikistan, Northern Mid-Atlantic, Pacific-Antarctic Ridge, Azores, Kyrgyzstan, Tajikistan, Hindu Kush, Sumatra,   

Bolivia to Dead Sea, Svalbard, Tonga, Kermadec Islands, Mayotte, Southwest Indian Ocean, East Africa, Hawaii, Antarctic Ridge, Greece, Turkey, Gulf of Alaska, Tonga, Fiji, Yukon, Canada,   

Papua New Guinea to Idaho, Nevada, Dead Sea, Svalbard, Southeast Pacific Rise, South of Africa, Black Sea, Montana, Yellowstone, Gulf of California, Southern California, Caucasus, Idaho, Ethiopia, Tanzania, Gulf of California, Alberta, Montana, West Chile Rise, Mozambique, Eastern Turkey, Baffin Bay, Tanzania, Idaho, Gulf of California, Easter Island, SW Russia, Utah, Yellowstone, Sonora, Mexico, Southern California,  

Gulf of Alaska to Gulf of Aden, Sumatra, Sunda Strait, Tarapaca, Chile, Bolivia, South Island, New Zealand, Ethiopia, Tanzania, Gulf of Aden, Northern Chile, South Chile Rise, Java, Bolivia, Sumatra, North Island, New Zealand, northern Chile, Bali, Indonesia, Sumatra, Central mid-Atlantic, Cook Strait, New Zealand, Central  Chile, Nicobar Islands, Australia, Java, Sumatra, Tarapaca, Chile,  


Node 4 (90 degrees)


Hawaii to Sichuan, China, Mongolia, Sumbawa, Northern Chile, 

Bolivia to

Papua New Guinea to Vancouver, Iran, 

Gulf of Alaska to Dead Sea, Kermadec Islands, Central Peru, Banda Sea, Sulawesi, Papua New Guinea, Iran, Myanmar, Kermadec Is, Molucca, Banda,  


Node 5 (72 degrees)


Hawaii to Panama, South of Panama, Quebec, New Guinea, Southeast Pacific Rise, 

Bolivia to Namibia, Nebraska, Southern California,

Papua New Guinea to China, Indian Ocean, Unimak, Alaska, Fox Islands,

Gulf of Alaska to Poland, northern Philippines, Galapagos, Panama, Czech Republic, Virgin Islands, Chiapas, Mexico, Galapagos, China, Poland, Puerto Rico, Netherlands Antilles, Virgin Islands, Central Pacific Ocean, Colombia, Tajikistan, China, France, Virgin Islands, Taiwan, Kazakhstan, South of Panama, Xinjiang, China,


Node 6 (60 degrees)


Hawaii to Alabama, Missouri, Gulf of Mexico, Guatemala, Chiapas, Mexico, Eastern Honshu, Japan,

Bolivia to Central Atlantic, Oaxaca, Guerrero, Mexico, Gulf of California, Tennessee,  

Papua New Guinea to Kamchatka, Kuril Islands,

Gulf of Alaska to Northern East Pacific Rise, Kyushu, Japan, Northern Marianas, El Salvador, Guatemala, Honduras, Reykjanes Ridge, Chiapas, Mexico,


Node 7 (52 degrees)


Hawaii to Kamchatka, Vanuatu, Nebraska, Mexico City, Oklahoma, Northern East Pacific Rise, New Caledonia, Kuril Islands, Guerrero, Oaxaca, Mexico,

Bolivia to Ascension Island, Oaxaca, Guerrero, Mexico,

Papua New Guinea to Hokkaido, Sichuan, China, Macquarie Island, Myanmar, Kuril Islands,

Gulf of Alaska to Michoacan, Mexico, Tokyo, Gulf of Mexico, South Carolina, Izu, Honshu, Japan, Iceland, Maine, Guerrero, Michoacan, Mexico,


Node 8 (45 degrees)


Hawaii to Tonga, Yellowstone,

Bolivia to

Papua New Guinea to Sumatra, Japan,  Tonga, New Zealand,  

Gulf of Alaska to Michigan, Maine, Durango, Mexico, Quebec, Hokkaido, Japan