Feeder dykes

As already discussed, in the Abitibi greenstone belt of the Superior craton, extensive dating of volcanic units, their inherited zircons, and feeder dykes cutting imits lower in the stratigraphy has established coherent stratigraphy where previous workers had proposed a tectonic collage. 

The large thicknesses of lava flows in basalt plateaux mean that such successions also could be considered for disposal sites. As with granite, basalt also can act as a shield against radiation and can disperse heat. Frequently, the contact between flows is tight and little pyroclastic material is present. Joints may not be well developed at depth and. strengthwise, basalt should support a cavern. Such basalt formations can be interrupted by feeder dykes and sills that may be associated with groundwater. Furthermore, the durability of certain basalts on exposure may be suspect (Haskins and Bell, 1995). 

This NE to NNE orientation is somewhat in disagreement with the NW- to NNW-oriented dyke proposed for SHV derived from geodetic or borehole strain data. Kenedi et al. (2010) propose an approximately N-S-oriented feeder dyke as a possible way to reconcile these competing models. 

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