Palaeomagnetic measurements on the Great Dyke, southern rhodesia

A series of serpentine, pyroxenite and norite samples from the Great Dyke were collected near Chingford, Lalapanzi and Selukwe. All the measurements were initially scattered, but upon demagnetization in a.c. fields a consistent grouping resulted in the case of the norite samples. The Curie point of the ferromagnetic phase in the norites was found using an automatically recording Chevallier balance. The Great Dyke is intruded into the Pre-Cambrian Basement complex and is itself regarded as Pre-Cambrian in age. From the mean site direction of magnetization an ancient pole position was found to be 10·7 N 68·9 E.