If one is able to travel into the past but at a spatial distance that puts him outside of his own past light cone would this be considered a causality violating trip? Looking at a Minkoski diagram, it would seem that one ought to be able to travel to a spatially displaced past without producing causality violations. In fact, I'm not sure you could even say whether this was the past of not for sure. 
For instance: If you found a one way wormhole, that took you outside of your own lightcone but into the past, could you say for sure that you traveled through time? Would this be a form of timetravel that did not violate causality? Note; I'm not necessarily suggesting that it is an FTL trip, it may be considered to be instantaneous teleportation, but in the reverse direction of x'.
Answer
Outside the light-cone, distances are spacelike and not timelike.
This means that you can always find a frame of reference such that your "spacially displaced past" is in the future for some other inertial frame of reference.
By definition, a spacelike distance is neither in the past nor the future. By itself, this would not create any causality violations.
Since wormholes (as shown in other answers) could set up a scenario where you do violate causality, I think you will find you cannot use wormholes to travel outside of your light-cone.
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