Properties of MagmaProperties of Magma

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Properties of MagmaProperties of Magma

Magma and lava are made up of Magma and lava are made up of elements and compounds. Elements elements and compounds. Elements are substances that can’t be broken are substances that can’t be broken down into a simpler substance. A down into a simpler substance. A compound is a substance that’s made compound is a substance that’s made up of 2 or more elements that are up of 2 or more elements that are chemically combined.chemically combined.

The compounds and elements that are The compounds and elements that are in lava and magma and the amounts of in lava and magma and the amounts of each tell us how the material behaves.each tell us how the material behaves.

Physical PropertiesPhysical Properties

In magma and lava a physical property In magma and lava a physical property that is important is viscosity. A physical that is important is viscosity. A physical property is a characteristic of that property is a characteristic of that substance that can be observed without substance that can be observed without changing the substance. Viscosity changing the substance. Viscosity measures the ability of a liquid to FLOW.measures the ability of a liquid to FLOW.

High viscosity: slow flow rates EX: High viscosity: slow flow rates EX: honeyhoney

Low viscosity: flows quickly EX: waterLow viscosity: flows quickly EX: water

What affects the viscosity of the What affects the viscosity of the liquid is the friction between the liquid is the friction between the particles: the higher the friction the particles: the higher the friction the higher the viscosity and the slower higher the viscosity and the slower the particles move.the particles move.

Magma’s viscosity depends on the Magma’s viscosity depends on the amount of silica and the temperature amount of silica and the temperature of the magma or lava.of the magma or lava.

Silica ContentSilica Content

Silica is particles of oxygen and silicon Silica is particles of oxygen and silicon combined. The more silica in the combined. The more silica in the magma the higher the viscosity and the magma the higher the viscosity and the slower the flow. (very sticky and light slower the flow. (very sticky and light colored, forms the rock rhyolite)colored, forms the rock rhyolite)

The less silica the magma has the lower The less silica the magma has the lower the viscosity and the faster it will flow.the viscosity and the faster it will flow.( dark colored and forms into basalt)( dark colored and forms into basalt)

Temperature and magmaTemperature and magma The higher the temperature the more the lava The higher the temperature the more the lava

will flow. ( low viscosity)will flow. ( low viscosity) The lower the temperature the slower the The lower the temperature the slower the

magma will flow. (High viscosity)magma will flow. (High viscosity) Most magma ranges in temp from 750 C to Most magma ranges in temp from 750 C to

1175 C.1175 C. Pahoehoe- is a type of lava that is fast moving Pahoehoe- is a type of lava that is fast moving

and hot looks like wrinkles and rope-like coils.and hot looks like wrinkles and rope-like coils. Aa- is a slow moving, cool type of lava that Aa- is a slow moving, cool type of lava that

forms rough jagged-looking rocks when it forms rough jagged-looking rocks when it cools.cools.

ViscosityViscosity

Viscosity VideoViscosity Video

Now you try it!Now you try it!