At depth the path followed by the dikes in the Cornucopia Gold Mining district, Oregon, is almost independent of the minor structural features of the area. At intermediate depths the dikes "roll" into and follow planar zones of weakness (faults, veins, etc.) for a short distance, roll out of the structurally weak zones, and continue to the surface at high angles. Minor changes in the strike and the dip of these dilation dikes, when they are in the plane of a vein, result in the displacement of portions of the vein alternately to the footwall and hanging wall of the dike.

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