Using a case study, assess whether the primary effects of a volcanic eruption are more or less significant than those of an earthquake. (8mks)

The primary effects of volcanic eruptions and earthquakes, those effects that occur as a direct result of the event, vary significantly due to the differing nature of the hazard involved and the differing magnitudes of each event. The differing impacts of the Chances Peak eruption in Montserrat (1995-97) and the 2016 (6.2 magnitude) Italian earthquake indicate that the primary effects of earthquakes may exceed that of volcanic eruptions, as 19 people were killed by the former (in pyroclastic flows) compared to nearly 300 by the latter (the majority of whom were trapped under or killed by collapsing buildings). This relates to it being impossible to predict the occurrence of an earthquake, meaning the people in towns such as Amatrice were not as prepared for the Italian earthquake as the people in Plymouth, Montserrat, who were evacuated when the volcano began to show warning signs, such as small earthquakes caused by underground magma build-up. Consequently 11 000 people were evacuated to the north part of Montserrat (a safe zone) in 1995, well ahead of the main eruption events in 1997, something that couldn’t happen in Italy as they had no capability to predict the earthquake. This shows that the primary effects of an earthquake may exceed those of a volcanic eruption as people in the affected area are more vulnerable as they have no warning of the impending event and therefore cannot evacuate. On the other hand, there is evidence that volcanic eruptions have greater primary effects than earthquakes as they affect a larger area. For example, on Montserrat the entirety of the capital city, Plymouth, was destroyed by pyroclastic flow (a primary effect of the eruption), where the only hospital on the island was located. Consequently the 11, 000 people evacuated didn’t have access to advanced local medical care, having to be transported to other islands for treatment. This damage far exceeds that of the 2016 Italian earthquake, which only made 4000 people homeless, thereby indicating the greater severity of the volcanic eruption’s primary impacts. However, this can also be seen as evidence of the event-specific nature of such events. Each volcanic eruption and earthquake is of a different magnitude and affects a different place, where they may be more or less prepared. For example, the impact of earthquakes varies significantly – the 2015 Nepal earthquake, for example, is estimated to have killed nearly 9000 people. Consequently, although I find that as volcanoes can be predicted and people evacuated from the hazard zone, something not possible in earthquakes, they have the most significant primary effects, it really depends on the individual event and location in question. Just as the magnitude of events, and therefore their possible impacts, changes, so does the level of preparation of the affected area.