Thorium and uranium in some pelitic rocks from the Dalradian,Scotland

Instrumental neutron-activation analysis for the determination of Th and U in rocks is superior to the delayed-neutron method when a low-power reactor is used. Results using these methods on pelitic rocks from the Dalradian of Scotland indicate Th values higher and U values lower than sediments from elsewhere. There is no evidence of Th or U movement during metamorphism and the areal variations found are due to the different provenance of the rocks.