In this modern era, a lot things happening, which will destroy human life and property. Geohazard is one of them. It is an Earth process that, upon interaction with human activity causes loss of life and property. A geohazard is a risk of a normally happening occasion will negatively affect people. This negative impact is the thing that we call a natural disaster. Among the natural hazards and possible disasters to be considered are earthquakes, volcanic eruptions, tsunami, landslides, subsidence, floods, droughts, hurricanes, tornadoes and asteroid Impacts. According to Parfitt and Wilson (2008), volcanic eruption can display an extensive range of hazard to both people and properties. One of world famous volcanic eruption was the eruption …show more content…
Besides volcanic gases, volcanic eruption will also emit lava flows, pyroclastic flows and lahar. Pahoehoe is one type of the lava which will enter the sea. Because of the high heat from lava can causes rapid boils of the sea. The seawater will evaporates and a series of chemical reaction will occur. This reaction produce lava haze or laze which contain a mixture of hydrochloric acid (HCL). Lava plumes is very acidic as it produces acid rain that fall on peoples and lands. It is very corrosive to the skin and clothing (Talwar & Satish Juneja, 2009). According to Parfitt and Wilson (2008), lava flows did not cause death to people directly. This is due to the slow movement of the lava flows. This make the people to escape after the eruption unless the people are sleeping in their house. However the authors explain that, the lava flow can bring massive damage to the properties. Sometimes, the lava is thick enough to bury and crush the building in the process. On the other hand, the extreme heat can ignite any flammable material and this cause the building to burn. One of the famous example is the burial of Pompeii and Herculaneum (1650) and eruption in Krakatoa (1883). Talwar & Satish Juneja, (2009) also agree that lava flow are slow so the death cause by it is uncommon. They also mention that lava flows can bury the homes and agricultural …show more content…
Lahar can quickly melts the snow and ice on the volcano. This can also provide water to the lahar. Talwar and Satish Juneja (2009) also mention that, the lahar also can bury the building s and land completely or partially. Sometimes due to high sediment discharge, it can bury the entire towns. Lahar also can trap people by destroying the bridges and roads. Pyroclastic flows is somehow similar like lahar but move with high speeds. It will also nearly destroy everything in its path. Parfitt and Wilson (2008), pyroclastic falls is really dangerous to humans and building. The fine grain pyroclasts will accumulate on top the roof of the buildings. It will stress apply on the weight applies on the building's structure, making it breakdown. It can also can make the tyres on the vehicles to melt. The ashes in the atmosphere will reduces the efficiency of the aircraft engine, so the engine might stop working. One of the real life examples is the DC-10 aircraft titled onto its tail by weight of air fall pyroclasts on June 15, 1991 due to the eruption of Mount Pinatubo in Philippines (1991). Parfitt and Wilson (2008) also explains about the Jokulhlaup which will cause flood that will destroy the roads and bridges in its