A probable Permian hydrothermal alteration age for a quartz syenite dyke from Stabben, Nordmøre.
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- Artikler 
A Rb-Sr whole-rock isochron from a quartz-syenite dyke at Stabben, Nordmøre, has provided an age of 263 +- 6Ma. This could be taken to indicate a crystallisation age for the dyke, i.e. Early Permian. The age, however, does not conform with an earlier published age for a similar dyke on the nearby island of Tustna, or with a published Middle\/Late Carboniferous palaeomagnetic pole for the Stabben dyke. It may be that the isochron is dating hydrothermal alteration of the dyke. The presence of such dykes with a deep mantle magmatic source, along the Møre-Trøndelag Fault Zone, emphasies the fundamental nature of the fault and indicates that a period of tensional conditions pertained during the time of emplacement of the dykes.