FAQ About Relationships Between Earthquakes and Volcanic Eruptions

Is there a relationship between earthquakes larger than magnitude 6 that occur along major fault zones and nearby volcanic eruptions?

Dawn, November 29, 1975 - Spatter from a part of the fissure on Kīlauea caldera
floor east of Halema‘uma‘u.

After large earthquakes the question of whether such strong events can trigger nearby volcanic eruptions often comes up.  The short answer to this question is: “not very often.”  There are a few examples in the historical record that suggest a connection between large earthquakes and volcanic eruptions, but even these, on close inspection, do not show a simple causative relationship. The most unambiguous case of triggering is probably the November 29, 1975 magnitude (M) 7.2 Kalapana, Hawai‘i earthquake, which was immediately followed by a small, and short-lived eruption at Kīlauea volcano, Hawai‘i.  However, in this case, the fault plane of the earthquake (i.e., the extent of the rupture) was directly beneath Kīlauea Volcano. Also, at the time of the earthquake, Kilauea was showing signs of pressurization and was likely poised to erupt soon anyway. Kīlauea is one of the most active volcanoes in the world, and erupted frequently in the decades before and after the 1975 earthquake.

May 24, 1960 - Ash-laden eruption plumes rise above fissure vent at Puyehue-Cordón
Caulle, Chile. Photo by Oscar Gonzá-Ferrán (University of Chile).
Archived with the Global Volcanism Program.

Another example of possible triggering occurred after the M9.5 Chile earthquake on May 22, 1960.  About 38 hours after the mainshock, Puyehue-Cordón Caulle in Central Chile erupted violently after being inactive for more than 25 years. In this instance, as at Kīlauea above, it is likely that the fault rupture extended beneath the volcano.

Establishing a statistical correlation between large earthquakes and subsequent volcanic eruptions requires a long and accurate record of both seismic and volcanic activity. The global record of such activity is sparse, especially for events that occurred before 1900. While there are hints of connections in some cases, and a few convincing anecdotes, statistical analyses to date have shown only a weak correlation. And, even if a statistical correlation is shown, working to establish and explain a causal connection is another matter entirely.

There are speculations in the literature, some backed by detailed experiments, about what mechanisms might be behind volcanic triggering by large earthquakes.  Mechanisms under consideration include:

  1. Stress changes caused by large earthquakes may either compress or expand nearby magma reservoirs. In the former case, the compression could increase the reservoir pressure, while in the latter case, the expansion could cause tensile (opening) fractures, around the reservoir.  Either way, conditions promoting eruption may become more favorable after a large nearby earthquake.

  2. High amplitude seismic waves passing through a magma reservoir may cause the nucleation of bubbles within the magma and/or the disturbance of previously stable layers within the reservoir.  Bubble creation can increase magma pressure, and layer destabilization can cause reservoir “overturn” where dense layers of relatively gas-poor magma sink forcing gas-rich magma to rise. Either of these events could prompt an eruption.

  3. Violent shaking during large earthquakes can create landslides, fractures, and other major ground disturbances that can affect shallow magma reservoirs, such as Kilauea’s in 1975, that are poised to erupt anyway.

There is clear evidence that large, distant earthquakes can, and do, trigger swarms of small earthquakes in active hydrothermal systems, such as those in Yellowstone and Long Valley calderas. This phenomenon has been observed at many volcanoes following large earthquakes; the M7.9 Denali Fault earthquake in Alaska is a good example. However, small earthquake swarms such as these are typically only recorded by sensitive seismic instrumentation and certainly do not fall into the category of an eruption.

Conversely, volcanic activity is known to trigger earthquakes. For example, swarms of small earthquakes, rarely larger than M5, can accompany the upward movement of magma through the Earth's crust. Also, large volumes of magma that rise from deep within the lower crust to shallower depths are thought to perturb the stress field around a volcano, possibly triggering small earthquakes up to 25 km away.

In conclusion, while it is possible that large earthquakes can trigger volcanic eruption in some cases, this connection is not well understood and as such not very useful for predicting the behavior of volcanoes. Data from well-designed local volcano monitoring networks remain the only reliable means for detecting volcanic unrest and forecasting volcanic activity.

Further Reading

Bautista BC, Bautista LP, Stein RS, Barcelona ES, Punongbayan RS, Laguerta EP, Rasdas AR, Ambubuyog G, and Amin EQ, Relationship of Regional and Local Structures to Mount Pinatubo Activity in: Newhall CG and Punongbayan RS (eds.), Fire and mud: Eruptions and lahars of Mt. Pinatubo, Philippines, Philippine Institute of Volcanology and Seismology, Quezon City and University of Washington Press, Seattle p. 351- 370.

Donne DD, Harris AJL, Ripepe M, and Wright R, 2010. Earthquake-induced thermal anomalies at active volcanoes, Geology, v.38 n.9, p.771-774.

Eggert S and Walter TR, 2009. Volcanic activity before and after large tectonic earthquakes: Observations and statistical significance, Tectnophysics, v.471 p.14-26.

Hill DP, Pollitz F, and Newhall C, 2002. Earthquake-volcano interactions: Physics Today, v.55, n.11, p.41-47.

Husen S, Wiemer S, and Smith RB, 2004. Remotely triggered seismicity in the Yellowstone National Park region by the 2003 Mw7.9 Denali fault earthquake, Alaska, Bulletin of the Seismological Society of America, v.94, n.6B, p.S317-S331.

Johnston MJS, Prejean SG, and Hill DP, 2004. Triggered deformation and seismic activity under Mammoth Mountain in Long Valley caldera by the 3 November 2002 Mw7.9 Denali fault earthquake, Bulletin of the Seismological Society of America, v.94, n.6B, p.S360-S369.

Lara LE, Naranjo JA, and Moreno H, 2004. Rhyodacitic fissure eruption in Southern Andes (Cordon Caulle; 40.5° S) after the 1960 (Mw:9.5) Chilean earthquake: a structural interpretation, Journal of Volcanology and Geothermal Research, v.138, p.127-138.

Macdonald GA, Abbott AT, and Peterson FL, 1983. Volcanoes in the Sea -- The geology of Hawaii (2nd edition), Honolulu, University of Hawaii Press, 517 p.

Walter TR, Wang R, Zimmer M, Grosser H, Luhr B, and Ratdomopurbo A, 2007. Volcanic activity influenced by tectonic earthquakes: Static and dynamic stress triggering at Mt. Merapi, Geophysical Research Letters, v.34 L05304.

Manga M and Brodsky E, 2006. Seismic Triggering of Erutpions in the Far Field: Volcanoes and Geysers, Annual Review of Earth and Planetary Sciences, v.34, p.263-291.

Newhall CG and Dzurisin D, 1988. Historic Unrest at Large Calderas of the World, U.S. Geological Survey Bulletin 1855, v.1, p.19-20.

Pozgay SH, White RA, Weins DA, Shore PJ, Sauter AW, and Kaipat JL, 2005. Seismicity and tilt associated with the 2003 Anatahan eruption sequence, Journal of Volcanology and Geothermal Research, v.143, i.1-3, p.60-76.

Tilling RI, Koyanagi RY, Lipman PW, Lockwood JP, Moore JG, and Swanson, DA, 1976. Earthquake and related catastrophic events, Island of Hawaii, November 29, 1975: A preliminary report: U.S. Geological Survey Circular 740, 33p.

White RA and Harlow DH, 1993. Destructive upper-crustal earthquakes of Central America since 1900, Bulletin of the Seismological Society of America, v.83, n.4, p.1115-1142.

White RA and Power JA, 2001. Distal volcano-tectonic earthquakes (DVT's): Diagnosis and use in eruption forecasting, Eos Transactions AGU, 82(47), Fall Meeting Supplement, Abstract #U32A-00012.