korjik wrote:How about you explain to us why you think Africa must have subduction zones around it?
The only reason any of us can think of is that you think that a growing africa plate implys a growing total surface area for the Earth, meaning that the Earth's volume must be increasing. That is why we have responded with the subduction being on the other side of the planet in the Pacific. If the Pacific plate is shrinking as fast as the Africa plate is growing, then the total volume of the Earth is constant and things are hunky-dory.
Strange wrote:Why do you think they can't move? They are just convection currents in a fluid. Why would you expect them to be stationary?
Strange wrote:Or then again, probably not. We have atmospheric patterns of high and low pressure where large masses of air move up and down by convection. These are not stationary, so I fail to see why you would expect similar phenomona in a different fluid not to move as well. Obviously, there are difference in things like viscosity and temperature differential which will chnage the behaviour somewhat (the timescales are much longer than for weather, for example) but the basic idea is the same.
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