Redirecting Lava.

I saw two volcano movies recently. In one Tommy Lee Jones used big concrete thingies to channel the lava. I’m thinking that the lava would burn the concrete just as easily as it burned everything else in its path.

But is there a way to redirect lava? Is there a material that can be built into barriers that won’t burn? Has this ever been tried?

Check out the book “The Control of Nature” by John McPhee. In it he relates the story of a harbor in Iceland that was saved from lava by the use of massive pumps and lots of seawater. They cooled the lava in place, which redirected the flow, preserving the harbor.

Look for Vestmannaeyjar on the web.

I remember a recent eruption in Italy where the build earth blockades to stop the lava flow.

In Volcano, Tommy Lee Jones made use of the flood control spillways in LA to divert the lava flow to the sea. Although there have been a couple of real-life successes with diversionary tactics in relation to smaller (or slower) eruptions, major eruptions would be impossible to control in the same way. There would just be too material coming out too fast to handle. In the cases of volcanos currently capped by snow and glaciers, like in the Pacific Northwest, you’d have the additional problem of all that snow and ice melting and mixing with ash and soil to form a massive mud flow called a lahar. Best thing you can do is get the hell out of the way as fast as you can.

As for the concrete burning - concrete that comes into direct contact with, and is covered by, lava won’t burn per se. Instead, it would be baked by the heat of the lava and altered into some other material, probably somewhat glassy depending on its initial composition (i.e., what’s mixed into the concrete). Think of the process as being similar to firing clay bricks in a kiln, except that the degree of baking decreases gradually as you move further from the contact between the lava and the concrete.