DISTANCE RELATIONS BETWEEN EARTHQUAKES
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)
Luzon, Philippines to
Easter Island to Pakistan,
Southern Peru to
Argentina to
Loyalty Islands to
Honshu Japan to
Sumatra to Colombia,
Outer shadow zone edge (141-148 degrees)
Luzon, Philippines to Puerto Rico, Nicaragua, Dominican Republic,
Easter Island to Turkey, Mongolia,
Southern Peru to Izu, Bonin Islands, Honshu, Japan, Mariana Is, Papua New Guinea,
Argentina to Kuril Is. Afghanistan, Flores, Timor, Indonesia, Mongolia,
Loyalty Islands to Turkey, Poland, Ukarine, Cyprus, Bulgaria, North Macedonia, Bosnia and Herzgovina, Eastern Mediterranean, Crete, Black Sea, Northern, Central Mid-Atlantic, Poland, Bulgaria, Turkey,
Honshu Japan to Ascension Island, Peru, Tarapaca, Chile,
Node 3 (120 degrees)
Luzon, Philippines to
Easter Island to
Southern Peru to Kuwait,
Argentina to Kuwait,
Loyalty Islands to Virginia, Haiti, New York State, Southern Iran,
Honshu Japan to Panama, North Atlantic, Puerto Rico,
P- and S- shadow zone edge and node 7 (101-110 degrees)
Luzon, Philippines to Central California,
Easter Island to Kamchatka, Komandorsky Is, South of Africa, Guam, Marianas,
Southern Peru to Turkey, Svalbard, Pribilof Is, South Island, New Zealand, Alaska Peninsula, Fiji, South of Alaska, Unimak Island, Alaska,
Argentina to
Loyalty Islands to Western Texas, Mongolia, Southern Texas, Oaxaca, Bouvet Is, Carlsberg Ridge, Ecuador, Argentina, eastern Mexico, Kashmir, Nicaragua, Texas,
Honshu Japan to North Atlantic Ocean, Oaxaca, Guerrero, Mexico,
Node 4 (90 degrees)
Luzon, Philippines to
Easter Island to
Southern Peru to England,
Argentina to Vancouver Islands,
Loyalty Islands to Southern Alaska, southern, central California, Gulf of California,
Honshu Japan to
Node 5 (72 degrees)
Luzon, Philippines to
Easter Island to
Southern Peru to Northern California,
Argentina to
Loyalty Islands to Sumatra, Kuril Islands,
Honshu Japan to Tonga, Fiji, Central California, Idaho, Tonga, Southern Iran,
Node 6 (60 degrees)
Luzon, Philippines to
Easter Island to
Southern Peru to Maine,
Argentina to
Loyalty Islands to Bonin Islands,
Honshu Japan to Vancouver,
Node 7 (52 degrees)
Luzon, Philippines to
Easter Island to
Southern Peru to
Argentina to Mid-Atlantic,
Loyalty Islands to Sulawesi, Indonesia,
Honshu Japan to Nicobar Islands, Kashmir, Tajikistan,