Abstract:
Most authors now accept that kimberlite magmatism was confined to cratons. M.A. Kamaletdinov, Yu. I. Kazantsev and other authors have now proved that within the Ural foredeep there are thick overthrust zones. Their data should allow us to reappraise the ore and particularly the diamond potential of the east edge of the East European craton. To estimate whether kimberlite magmatism occurred here, we tried to reinterpret the data of 1:200,000-scale areomagnetic surveys. Complex magnetic anomalies were divided into their components on the basis of the different curve slopes; then individual anomalies were interpreted by the tangent method. On the basis of magnetization intensity, these anomalies can be sudivided into three types - virtually nonmagnetic, slightly magnetic and magnetic. Analysis suggests that the kimberlite magmatism dates from Late Permian-Triassic time and is a dynamic reflection of the synchronous intercontinental rifting which encompassed the Arctic, Siberian and Kazakhstan young platforms.