# Boyle's Law

1. Dec 1, 2013

### lollikey

I have been trying to find out of Boyle's Law and plate tectonics are in any way shape or form related. Are they?
If they are not, is there a way I can relate their movement to physics?

2. Dec 1, 2013

### Staff: Mentor

Boyle's law describes the ideal gas, plates are solids. Why should they be described by an unrelated law?

3. Dec 1, 2013

### lollikey

that is the hint my teacher gave me because of magma

Last edited: Dec 1, 2013
4. Dec 1, 2013

### jim mcnamara

What was the question? The whole thing, please.

5. Dec 9, 2013

### 256bits

Well, plate tectonics and magma do have a relationship so I will give it a try.
A full textbook is needed to understand it all of which I have at most about 2%.
Edit: Words I am using from your post are Plate Tectonics, Magma, Boyles law.

A map of volcanic activity will show that where plates meet up there is an increased activity of volcanoes, or the outpouring of magma onto the surface as lava or as explosive eruptions, with most volcanic activity occuring at these plate boundaries.

Magma is molten rock. And it is under pressure. For a solid or liquid, if the pressure decreases the change in volume is unsubstantial. For a gas the volume change is dramatic. If the magma has a quantity of entrained gas, and it reaches the surface where the pressure is reduced, the outflow would be explosive, even at the possibility of blowing the top of the previously ( if so formed ) volcanic mountain. Or the side, such as what happened at Mt St-Helens.

Magma with a low entrained quantity of gas would just ooze out of the fissure such as what you see around Hawaii, or as fountains of lava where the gas is being expelled bringing along with it some of the molten rock.

Magma also has a viscosity. Thick magma would most likely not let the entrained gases seep out as quickly as a low viscosity magma, so that also has a bearing on how the magma will extrude to the surface and the type of lava flows seen.

You should investigate the composition of magma and entrained gases, with water and CO2 being the most common I believe.

So, one has the viscosity of the magma, the decrease in pressure and Boyles Law and volume expansion of gases, and the amount of entrained gases to take into account for the type of eruption.

6. Dec 9, 2013

### Staff: Mentor

I have no problems with using Boyle's law to explain volcano eruption, but plate tectonics is a separate thing. For most of the time plate movements have nothing to do with the gases and changes in their volume.