What determines whether a volcano erupts explosively or quietly?
Whether an eruption is quiet or explosive depends on the magma's silica content and whether the magma is thin and runny or thick and sticky. Silica is a material found in magma that is formed from the elements oxygen and silicon. A volcano erupts quietly if its magma is low in silica.
What affects whether a volcano will erupt explosively or non explosively?
The amount of dissolved gas in the magma provides the driving force for explosive eruptions. The viscosity of the magma, however, is also an important factor in determining whether an eruption will be explosive or nonexplosive.
Which of the following does not affect viscosity of magma?
Temperature Silica Content Amount of gas None of these affects the viscosity of the magma.
What magma doesn’t explode explosively?
Effusive (Non-explosive) Eruptions Non explosive eruptions are favored by low gas content and low viscosity magmas (basaltic to andesitic magmas). If the viscosity is low, non-explosive eruptions usually begin with fire fountains due to release of dissolved gases.
Why do volcanoes erupt explosively and silently?
Volcanoes erupt explosively or quietly, depending on the characteristics of the magma. Magma can vary in viscosity, the resistance to flow. Magma with high viscosity is thick and resists flowing. Magma with low viscosity is thin and flows easily.
Why would a volcano erupt explosively?
A volcano's explosiveness depends on the composition of the magma (molten rock) and how readily gas can escape from it. As magma rises and pressure is released, gas bubbles (mainly of water vapor and carbon dioxide) form and expand rapidly, causing explosions.
When a volcano erupts quietly what kind of mountain forms?
Volcanoes
| A | B |
|---|---|
| When a volcano erupts quietly what kind of mountain forms? | shield volcano |
| A weak spot in the crust where magma comes to the surface is called what? | a volcano |
| How well a liquid flows depends on what? | it's viscosity |
| A long tube that connects a magma chamber to the surface is called what? | pipe |
Which of the following does not affect the viscosity?
Capillary action does not affect the viscosity of a liquid.
How does viscosity affect volcanic eruptions?
Ultimately, the viscosity of a magma will determine the shape a volcano takes over continued eruptions. A magma's silica content will not only control the rock type that forms, it also controls the relative viscosity of the magma. Differences in a magma's viscosity will determine the shape a volcano takes.
How does magma temperature affect a volcanic eruption?
Both the temperature and mineral content of magma affect how easily it flows. The viscosity (thickness) of the magma that erupts from a volcano affects the shape of the volcano. Volcanoes with steep slopes tend to form from very viscous magma, while flatter volcanoes form from magma that flows easily.
What causes magma to erupt?
The magma rises and collects in chambers within the crust. As magma fills the chamber, pressure grows. If the pressure gets high enough, the magma can break through the crust and spew out in a volcanic eruption.
How do explosive volcanic eruptions and quiet volcanic eruptions differ from each other?
The two primary determinants of the type of volcanic eruption are the magma's viscosity — degree of liquidity — and gas content. Volcanoes that produce explosive eruptions tend to have thicker, more viscous magma, and a greater volume of gas.
What is quiet eruption?
Quiet Eruptions Volcanoes that have very hot, low-silica magma generally erupt quietly. In a quiet eruption, lava erupts in a stream of low-viscosity lava, called a lava flow. Lava flows from a quiet eruption can travel for great distances.
Does a volcano erupts quietly if its magma is thick and sticky?
A volcano erupts quietly if its magma is thick and sticky. Complete the table to describe the different types of lava. What is a pyroclastic flow? A pyroclastic flow occurs when an explosive eruption hurls out ash, cinders, and bombs.
What factors effect viscosity?
Increase in temperature decreases viscosity. Increases in pressure increase viscosity in liquids. In water, it decreases whereas, in gases, it remains the same.
- Increase in temperature decreases viscosity.
- Increases in pressure increase viscosity in liquids. In water, it decreases whereas, in gases, it remains the same.
What are the 4 factors that affect viscosity?
The viscosity of a material is affected by temperature, pressure, nature of fluid, velocity gradient , etc.
How does viscosity affect magma?
Heating reduces viscosity (warm syrup flows more easily than cold.) High viscosity lavas flow slowly and typically cover small areas. In contrast, low viscosity magmas flow more rapidly and form lava flows that cover thousands of square kilometers.
Does temperature affect volcanic eruptions?
The researchers, from the University of Cambridge and the UK Met Office, say that large-magnitude eruptions will have greater effects as the climate continues to warm. However, the cooling effects of small- and medium-sized eruptions could shrink by as much as 75%.
What is the cause and effect of volcanic eruption?
Although there are several factors triggering a volcanic eruption, three predominate: the buoyancy of the magma, the pressure from the exsolved gases in the magma and the injection of a new batch of magma into an already filled magma chamber. What follows is a brief description of these processes.
What is the effect of volcanic eruption?
Volcanoes spew hot, dangerous gases, ash, lava, and rock that are powerfully destructive. People have died from volcanic blasts. Volcanic eruptions can result in additional threats to health, such as floods, mudslides, power outages, drinking water contamination, and wildfires.
Why does a volcano erupt explosively?
A volcano's explosiveness depends on the composition of the magma (molten rock) and how readily gas can escape from it. As magma rises and pressure is released, gas bubbles (mainly of water vapor and carbon dioxide) form and expand rapidly, causing explosions.
What type of magma causes explosive eruptions?
andesitic Explosive eruptions are favored by high gas content & high viscosity magmas (andesitic to rhyolitic magmas). The explosive bursting of bubbles fragments the magma into clots of liquid that cool as they fall through the air. These solid particles become pyroclasts or volcanic ash.
Which of the following does not affect viscosity?
Capillary action does not affect the viscosity of a liquid.
What affects viscosity of magma?
Viscosity of Magmas Viscosity depends on primarily on the composition of the magma, and temperature. Higher SiO2 (silica) content magmas have higher viscosity than lower SiO2 content magmas (viscosity increases with increasing SiO2 concentration in the magma).
What is viscosity affected by?
Viscosity is influenced by the composition of the crude oil, the temperature, dissolved gas content, and the pressure. As temperature increases, the viscosity will decrease.
What are the effect of volcano eruption?
Volcanoes spew hot, dangerous gases, ash, lava, and rock that are powerfully destructive. People have died from volcanic blasts. Volcanic eruptions can result in additional threats to health, such as floods, mudslides, power outages, drinking water contamination, and wildfires.
How do volcanic eruptions affect weather quizlet?
How does a volcanic eruption affect climate change? Ash blocks sunlight, causing temperatures to drop.
What factors affect volcanic eruptions?
The style of eruption depends on a number of factors, including the magma chemistry and content, temperature, viscosity, volume and how much water and gas is in it, the presence of groundwater, and the plumbing of the volcano. gases and lava.
Who is affected by volcanic eruptions?
Exposure to ash can be harmful. Infants, elderly people, and people with respiratory conditions such as asthma, emphysema, and other chronic lung diseases may have problems if they breathe in volcanic ash. Ash is gritty, abrasive, sometimes corrosive, and always unpleasant.
How do volcanic eruptions affect weather?
The gases and dust particles thrown into the atmosphere during volcanic eruptions have influences on climate. Most of the particles spewed from volcanoes cool the planet by shading incoming solar radiation. The cooling effect can last for months to years depending on the characteristics of the eruption.