Dike Tip, Oslo, Norway - Interpreted

There is a fair bit going on in this image. The dikes and joints are sub-parallel to each other, suggesting some type of linkage. One possibility is that the joints were already present and the younger dikes intruded along this weakness plane.In turn the joints and dikes are roughly perpendicular to bedding, which was rotated to its vertical position during the Caledonian orogeny in this area (you are not expected to have known this).

The one dike appears to be offset by a slip/fault surface along bedding with the top moving to the right. Bedding is often a good slip surface, so this makes sense, but there is an alternate interpretation. A careful look shows a shin grey and fine-grained chill zone along the edge of dike intrusions (where the magma solidified more quickly). A close look shows that margin to follow the possible fault surface and not be cut by it (you will need to go back to the uninterpreted image to really see this). This would suggest slip occurred during injection before the magma solidified. In this case it is a bit like a spreading ridge and a transform fault, and the top moved to the left, and the slip only occurred along the part that links to two dike segments.

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