[bert]

Iceland exists along the rift between two tectonic plates that are continuously being pulled apart. As the scab covering the parting line thins, the pressure allows venting through the opening.

The so called cyclic events are actually the scab formation or magma clotting along the line of the opening. The whole line is moving and the parting line will be penetrated whenever it thins below the thickness required to hold the pressure.

We lack the ability to measure the scab thickness and thus make some estimate of the probability of a breakthrough somewhere else along the line. We can only watch.

[Travis McGee]

THanks for the simple, and “visual” explanation. You conveyed more information in a few sentences than I’ve gleaned in long articles.