Palaeomagnetism of the Dykes from Kolar Gold Mines, India

Results of the palaeomagnetic studies on five dykes intruding the Archaean schists from the Nundydroog mine (lat. 12°57', long. 78°15") of the Kolar Gold Fields are reported. Three dykes have given consistent and stable directions after cleaning in an alternating field of 150-200 oe. The virtual geomagnetic poles (VGP's) of these dykes are 47°N, 163°W; 50°N 36°W; and 45°N, 30°W. A Precambrian polar wandering curve for India is drawn taking into consideration radiometric ages and the palaeomagnetic data, available from the formations other than the dykes. Based on this polar wandering curve the ages of the dykes are interpreted. It is suggested that these dykes occupy the fractures which were probably formed during Precambrian times, due to an East-West compressive stress. Continental drift in Precambrian era is indicated.