A type of transform fault in which there is production of basaltic magma along the fault plane, indicating some separation of the blocks on each side of the fault. Such transform faults do not exactly follow arcs of small circles about the pole of rotation of the relevant plate pair. An example is the Azores Fracture Zone, which forms the boundary between the Eurasian and African Plates from the Mid-Atlantic Ridge into the Mediterranean. Leaky transform faults are one kind of combined plate margin.