The relationship between tectonic earthquakes and volcanoes is one of the most striking, but yet less well-understood topics in earth sciences, due to the lack of observational data. When this interaction occurs, volcanoes may react in the short term (hours to days) to long term (months to decades), causing an eruption, which suggests that what happens inside the volcano to trigger this new eruption needs time. In 2012, three large earthquakes struck Central America, and some volcanoes erupted days after, while others took erupted months to years after the earthquakes to enter into an eruption. This poses to the question: was the eruption triggered by the earthquakes? Here I show that the large earthquakes contributed to the increment in the number of volcanic eruptions in the region. I found that only volcanoes were already undergoing a certain degree of unrest and without large eruptions previous to the large tectonic earthquakes erupted, thus suggesting that the volcanoes were nearly ready to erupt and that the earthquakes helped, but not necessarily caused the volcanic eruptions. The present research can become a tool for forecasting volcanic activity when a large earthquake hits a region if the volcanic activity is previously well monitored and to communicate and prepare the population and to reduce the volcanic risk if the protocols are well established.
Keywords: Earthquake and volcano interaction, volcanic eruptions, volcanic unrest, stress, Monte Carlo method.