What is the viscosity of lava?

Because of their lower silica content and higher eruptive temperatures, they tend to be much less viscous, with a typical viscosity of 3.5 × 106 cP at 1,200 °C (2,190 °F). This is slightly greater than the viscosity of smooth peanut butter.

What is the viscosity of lava determined by?

A magma’s viscosity is largely controlled by its temperature, composition, and gas content (see downloadable programs at the bottom of this page). The effect of temperature on viscosity is intuitive. Like most liquids, the higher the temperature, the more fluid a substance becomes, thus lowering its viscosity.

What is the viscosity of Mt Etna?

1800 eruption had viscosities as low as 50–60 Pa s, channel velocities of up to 9–12 m/s (near the vent) and effusion rates of 100–200 m3/s (Kauahikaua et al., 2002).

Does lava have high viscosity?

Even though lava is 100,000 times more viscous than water, it can still flow great distances. When lava has low viscosity, it can flow very easily over long distances. But most importantly, highly viscous lava is associated with explosive eruptions and dangerous pyroclastic flows.

What are 4 types of lava?

The most common way to divide lava flows into distinct types is following: Pahoehoe lava flow, Aa lava flow, Blocky lava flow, and also Pillow lava flow.

Which lava flows fastest?

PAHOEHOE – has a shiny, smooth, glassy surface. It tends to be more fluid (lower viscosity), hence flows more quickly and produces thinner flows (typically 1-3 m).

How does the viscosity of lava affect its flow?

Even though lava is 100,000 times more viscous than water, it can still flow great distances. When lava has low viscosity, it can flow very easily over long distances. This creates the classic rivers of lava, with channels, puddles and fountains.

Which is more viscous mafic lava or felsic lava?

The viscosity of lava isdetermined partly by the amount of silica in the magma. Lava which contains a high percentage of silica is called felsic. If the lava contains around 50% silica, it is called mafic or basaltic. Felsic lavas tend to be more viscous than basaltic lavas.

What kind of lava has a high percentage of silica?

Lava which contains a high percentage of silica is called felsic. If the lava contains around 50% silica, it is called mafic or basaltic. Felsic lavas tend to be more viscous than basaltic lavas. Low viscosity (basaltic) lavas flow freely from volcanoes to form flat sheets of lava, which can cover large areas.

What are the different types of lava flows?

Most lava flows are basaltic in composition. There are three main types of lava flow:-. PAHOEHOE – has a shiny, smooth, glassy surface. It tends to be more fluid (lower viscosity), hence flows more quickly and produces thinner flows (typically 1-3 m).