What evidence has led scientists to conclude that the earth's outer core is liquid?

Answer 1

Because S waves can not go through the outer core.

Answer 2

Peering into the crater of some active volcanoes one may actually see the liquid interior sloshing back and forth. The Hawaiian volcanoes are one such, and Mt Erebus in Antarctica is another.

So, simple observation is the first answer.

However, the innermost core of the Earth is believed to be solid, for as the pressure on a substance increases, its melting point goes rises. The Inner Core of the Earth is under such pressure that it is solid.

This may be inferred from the fact that shear waves (from earthquakes) may be transmitted through the inner core. Since shear waves cannot be transmitted through a liquid - therefore the inner core is solid. Laboratory experiments at extreme pressure support this hypothesis.

Answer 3

Primary waves (p waves) from earthquakes are able to travel through solids and liquids. Secondary waves (S waves) are only able to travel through solids. Scientists studied and measured these waves when large earthquakes occurred in the past, did a whole bunch of math, and wala!: it is now accepted that earth's outer core is liquid.

Answer 4

Scientists have studied the different paths that P waves and S waves take inside earth. P waves bend in a pattern indicating the existence of a layer between the core and the mantle. Since S waves cannot travel through the outer core, geologists have concluded that this layer is liquid.

Answer 5

Geophysical methods support this idea mainly on the basis of seismological studies and earth's magnetic field.

a) The S-waves vanish reaching the outer core which suggest that it is liquid because S waves are not supposed to pass fluids.

b) The Geomagnetic field is also thought to be originating from outer core because In iron and nickle in molten form produces eddy currents producing magnetic field. This is proved by laboratory experiment. Molten metals were filled in a globe and globe was spinned which produces magnetic field around it.

Answer 6

answer: s-waves come to a complete stop in the outer core.. S-waves are reflected because they cannot travel through liquids

Answer 7

When scientists send seismic waves down through the Earth, they slow down when they reach the outer core. This means that the outer core is somewhat liquid.

Answer 8

Because S waves can not go through the outer core.

Answer 9

Because of volcanoes erupting molten lava.