Correlations between earthquakes and large mud volcano eruptions

Abstract

[1] We examine the potential triggering relationship between large earthquakes and methane mud volcano eruptions. Our data set consists of a 191-year catalog of eruptions from 77 volcanoes in Azerbaijan, central Asia, supplemented with reports from mud volcano eruptions in Japan, Romania, Pakistan, and the Andaman Islands. We compare the occurrence of historical regional earthquakes (M > 5) with the occurrence of Azerbaijan mud volcano eruptions and find that the number of same-day earthquake/ eruption pairs is significantly higher than expected if the eruptions and earthquakes are independent Poisson processes. The temporal correlation between earthquakes and eruptions is most pronounced for nearby earthquakes (within $100 km) that produce seismic intensities of Mercalli 6 or greater at the location of the mud volcano. This assumed magnitude/distance relationship for triggering observed in the Azerbaijan data is consistent with documented earthquake-induced mud volcano eruptions elsewhere. We also find a weak correlation that heightened numbers of mud volcano eruptions occur within 1 year after large earthquakes. The distribution of yearly eruptions roughly approximates a Poisson process, although the repose times somewhat favor a nonhomogenous failure rate, which implies that the volcanoes require some time after eruption to recharge. The volcanic triggering likely results from some aspect of the seismic wave's passage, but the precise mechanism remains unclear.

Frequency dependence of mud volcano response to earthquakes

“…They are, however, consistent with previous compilations of observations that relate earthquake magnitude and distance over which triggered eruptions occur [Mellors et al, 2007;Manga et al, 2009;Bonini, 2009]. The magnitude-distance relationship shown in Figure 1 does not support an earthquake-trigger for the Lusi eruption.…”

Large historical eruptions at subaerial mud volcanoes, Italy

“…Cyclicity may arise from feedbacks between the mud sources and its ascent (Zoporowski and Miller, 2009). Local and regional earthquakes with large enough magnitude have also been shown to increase eruption rate or initiate new eruptions (Mellors et al, 2007;Manga et al, 2009;Bonini, 2009). However, violent eruptions can also occur in the absence of seismicity (Bonini, 2009).…”

Proceedings of Fringe 2015: Advances in the Science and Applications of SAR Interferometry and Sentinel-1 InSAR Workshop

“…The deformation of both the AyazAkhtarma and the Khara-Zira Island mud volcanoes is likely linked to an increase of internal pressure. This hypothesis is supported by the fact that it has long been recognized that mud volcano activity is driven by internal fluid pressure changes [e.g., 2,23,24,22]. It is worth noting that at least a part of the mud volcano undergoes bulging before an eruption.…”

“…The Khara-Zira island occurs offshore southsouthwest of Baku and is one of the islands built by mud volcanoes in the Caspian Sea [22,21]. The Khara-Zira island is elliptical in shape (with maximum length of ~2.4 km) and is topped by a rather flat surface.…”