1.   The possibility of such a mid-plate quake thus carries a much higher risk than one on a plate boundary.

2.   They occurred nowhere near a plate boundary.

3.   There are three types of plate boundary.

4.   It is quite clear, however, that marked deformation does in fact occur within some continental regions which are thousands of kilometres away from the nearest plate boundary.

5.   Except where subduction zones lie adjacent to mountain belts on continental margins, plate boundaries do not coincide with continental coastlines.

6.   The effect is clearly illustrated in the alignment of transform faults which mark the off-sets along either side of divergent plate boundaries.

7.   A collision margin can take a number of forms, depending on the characteristics of the interacting plate boundaries.