Does Lava Have the same properies as water? In other Words does Lava seek it's own level etc.

rocky CHRIS KOFRON

Dear Chris,

Lava is a fluid, so in some properties that are similar to water, but there are also some pretty big differences. For one thing the viscosity of lava is at least 1 million times higher than that of water. That means that a blob of lava would flow much slower down a slope than the same volume of water. Another big difference is that lava cools as it flows, and its viscosity goes even higher as it cools. Another big difference is that a skin forms on lava very quickly (by cooling) so that even if the interior is still flowing, it will have to stretch or fracture that skin in order to go anywhere.

So...lava will tend to find the lowest area to flow because it is flowing under the force of gravity. If you only look at a small part of a lava flow it might seem to be flowing uphill. For example, you can sometimes find a pahoehoe toe that is expanding upward and the surface on top may even fracture so that lava is welling out of this top crack. If you only look at that limited picture then you'd say the lava was flowing uphill. But, the lava is just following the path of least resistance. In these cases the side skins are too difficult to deform so the top fractures. If you compare the elevation of the vent to the elevation of the flowing tip of lava, even though it may be traveling upward over a distance of a few centimeters, the overall flow is downhill.

Scott Rowland, University of Hawaii 

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