Hazards Produced by volcanic activity
As with all tectonic activity, volcanoes become hazardous when they interact with human communities and activities
1. Use pages 476- 478 to complete the sheet below. You should describe and explain the characteristics of each hazard and include examples of where they have
occurred.
2. Additional sites to use: Volcano Information centre. USGS hazards website
Lava Gas Emissions Pyroclastic Flows
Lava is melted molten rock material which erupts from a
Magma from volcanoes consist of dissolved gases, which when A secondary hazard of volcanoes in which a fast-moving avalanche of
magma plume and flows on the Earths surface. Depending
erupted, causes air pollution. Examples of gases would be water rock, ash and gas is produced. It can form from the failure of a lava
upon the content of silica, the lava can be very viscous or vapour, carbon dioxide, sulphur dioxide and hydrogen. Even when dome or as a result of an eruption (collapse of a plume). It normally
not viscous at all. This is also dependent upon the eruptions do not occur, gases can escape through fumaroles. When has a high concentration and temperature. In regards to buildings and
temperature and dissolved gases. There are 2 types of gases react with rain, it can cause acidic rain. This has massive impacts humans, it can destroy all buildings by its force and the materials it
magma: acidic and basic. If it comes into contact with on humans and vegetation as corrosion occurs. In addition, there is a carries. It affects humans by causing fatalities as the gases are
lack of oxygen in the air that can cause rare mass killings. Such a case poisonous. As seen in Pompeii, the ash can also bury the landscape
humans or buildings, it will inevitably melt materials and
was involved in Cameroon at Lake Nyos where the volcanic gases (Mount Vesuvius).
crops but rarely causes fatalities. An example would be
from, volcanic craters, seeped into the river from a deep lake.
Kilauea Volcano with basaltic lava.
Ash & Tephra Lahars Landslide/ debris avalanches
This is the volcanic material that is ejected into the air. Unlike pyroclastic Lahars are a type of mudflow with the consistency of wet concrete. Debris avalanches are the sudden catastrophic collapse (landslide)
flows, it is just molten rock fragments that come from the eruption Snow and ice on the volcano could melt during an explosion and flow from an unstable side of a volcano. Rising magma, earthquakes and
column (airborne pyroclastic accumulation). The largest fragments fall down the flanks. This mixes with the Tephra’s and the pyroclastic weakening can be caused by hydrothermal alterations and heavy rain
back onto the volcano vent, small fragments rise in the air forming a larger flows. It can usually travel at 50mph and can destroy things close to can trigger a debris avalanche of unstable materials. Due to gravity,
eruption column. This also contributes to eruption clouds. These have a the source. The usually rip up trees, houses and boulders downstream. the materials move down the flanks very quickly. It can turn into a
significant impact on properties and crops, as they become damaged and It has also been argued to be one of the most dangerous hazards as lahar if the debris evolves and continues downslope. An example of a
buried. Also, the fine materials could clog human lungs and airplane they can occur with or without an eruption. Waters can also come place which experiences debris avalanches could be the British
motors, stopping any travelling from occurring. In some scenarios, the from rainfall and a breakdown of a summit crater. An example of a Columbian islands.
tephra is hot which can start fires causing leached chemicals. An example place which suffers lahars can be Cascade Range in the western US,
of a tephra would be in Eyjafjallajökull in Iceland. near a stratovolcano
Acid Rain
Acid rain is rainfall that has a high acidity caused by
atmospherically pollution from volcanic eruptions. The sulphur
Lava Bombs Lighting
dioxide and nitrogen oxides released in the air causes acidic rain.
Lava bombs are partially melted chunks of rock that explode out of Lightening is a naturally occurring electrical discharge in regions of
Acidic rain rarely harms humans but it can cause severe health
volcanic vents during eruptions. When they are exposed to the air, they the atmosphere. They can occur during volcanic eruptions. The tiny
issues such as chronic lung problems. Acid rain has detrimental
harden and crash on the volcanic surface due to gravity. They are a particles that make up the plume are tightly compressed beneath the
effects on crops and tress, damaging them and can weather away
significant hazard of eruptions as they can cause severe injuries and volcano and when the charges become too great for the air to resist,
buildings and statues. An example where acid rain has been
deaths to people in an eruption zone. In addition to this, they can cause lightening occurs. This can be dangerous for humans if they are
prevalent, as a result of volcanic eruptions, has been Laguna
the destruction of houses, especially if they haven’t cooled down. Lava struck by lightning however, it only occurs between the eruption
Caliente crater of Poás. Here, inhabitants nearby suffered with
bombs have occurred in Canary Islands, Cumbre Vieja and La Palma clouds and the column near the crater, so it only affects those who
irritation to the eyes and lungs.
are in the eruption zone. An example where this has occurred was on
Sakurajima, the Japanese island of Kyushu
As with all tectonic activity, volcanoes become hazardous when they interact with human communities and activities
1. Use pages 476- 478 to complete the sheet below. You should describe and explain the characteristics of each hazard and include examples of where they have
occurred.
2. Additional sites to use: Volcano Information centre. USGS hazards website
Lava Gas Emissions Pyroclastic Flows
Lava is melted molten rock material which erupts from a
Magma from volcanoes consist of dissolved gases, which when A secondary hazard of volcanoes in which a fast-moving avalanche of
magma plume and flows on the Earths surface. Depending
erupted, causes air pollution. Examples of gases would be water rock, ash and gas is produced. It can form from the failure of a lava
upon the content of silica, the lava can be very viscous or vapour, carbon dioxide, sulphur dioxide and hydrogen. Even when dome or as a result of an eruption (collapse of a plume). It normally
not viscous at all. This is also dependent upon the eruptions do not occur, gases can escape through fumaroles. When has a high concentration and temperature. In regards to buildings and
temperature and dissolved gases. There are 2 types of gases react with rain, it can cause acidic rain. This has massive impacts humans, it can destroy all buildings by its force and the materials it
magma: acidic and basic. If it comes into contact with on humans and vegetation as corrosion occurs. In addition, there is a carries. It affects humans by causing fatalities as the gases are
lack of oxygen in the air that can cause rare mass killings. Such a case poisonous. As seen in Pompeii, the ash can also bury the landscape
humans or buildings, it will inevitably melt materials and
was involved in Cameroon at Lake Nyos where the volcanic gases (Mount Vesuvius).
crops but rarely causes fatalities. An example would be
from, volcanic craters, seeped into the river from a deep lake.
Kilauea Volcano with basaltic lava.
Ash & Tephra Lahars Landslide/ debris avalanches
This is the volcanic material that is ejected into the air. Unlike pyroclastic Lahars are a type of mudflow with the consistency of wet concrete. Debris avalanches are the sudden catastrophic collapse (landslide)
flows, it is just molten rock fragments that come from the eruption Snow and ice on the volcano could melt during an explosion and flow from an unstable side of a volcano. Rising magma, earthquakes and
column (airborne pyroclastic accumulation). The largest fragments fall down the flanks. This mixes with the Tephra’s and the pyroclastic weakening can be caused by hydrothermal alterations and heavy rain
back onto the volcano vent, small fragments rise in the air forming a larger flows. It can usually travel at 50mph and can destroy things close to can trigger a debris avalanche of unstable materials. Due to gravity,
eruption column. This also contributes to eruption clouds. These have a the source. The usually rip up trees, houses and boulders downstream. the materials move down the flanks very quickly. It can turn into a
significant impact on properties and crops, as they become damaged and It has also been argued to be one of the most dangerous hazards as lahar if the debris evolves and continues downslope. An example of a
buried. Also, the fine materials could clog human lungs and airplane they can occur with or without an eruption. Waters can also come place which experiences debris avalanches could be the British
motors, stopping any travelling from occurring. In some scenarios, the from rainfall and a breakdown of a summit crater. An example of a Columbian islands.
tephra is hot which can start fires causing leached chemicals. An example place which suffers lahars can be Cascade Range in the western US,
of a tephra would be in Eyjafjallajökull in Iceland. near a stratovolcano
Acid Rain
Acid rain is rainfall that has a high acidity caused by
atmospherically pollution from volcanic eruptions. The sulphur
Lava Bombs Lighting
dioxide and nitrogen oxides released in the air causes acidic rain.
Lava bombs are partially melted chunks of rock that explode out of Lightening is a naturally occurring electrical discharge in regions of
Acidic rain rarely harms humans but it can cause severe health
volcanic vents during eruptions. When they are exposed to the air, they the atmosphere. They can occur during volcanic eruptions. The tiny
issues such as chronic lung problems. Acid rain has detrimental
harden and crash on the volcanic surface due to gravity. They are a particles that make up the plume are tightly compressed beneath the
effects on crops and tress, damaging them and can weather away
significant hazard of eruptions as they can cause severe injuries and volcano and when the charges become too great for the air to resist,
buildings and statues. An example where acid rain has been
deaths to people in an eruption zone. In addition to this, they can cause lightening occurs. This can be dangerous for humans if they are
prevalent, as a result of volcanic eruptions, has been Laguna
the destruction of houses, especially if they haven’t cooled down. Lava struck by lightning however, it only occurs between the eruption
Caliente crater of Poás. Here, inhabitants nearby suffered with
bombs have occurred in Canary Islands, Cumbre Vieja and La Palma clouds and the column near the crater, so it only affects those who
irritation to the eyes and lungs.
are in the eruption zone. An example where this has occurred was on
Sakurajima, the Japanese island of Kyushu
