Fluid-tectonic mobilization of the buried crusts of kimberlite weathering and origin of the Urals diamond deposits

There are no primary diamondiferous rocks on the Urals. The diamond contain ing rocks are represented by clay bodies that are intruded into quartzitic sandstone. The quartzitic sandstone is disaggregated to sand before the cla y bodies are intruded. The diamond deposits are located around a low-angle overthrust. The geological structure of the diamond deposits, the compositi on of the diamond containing rocks and the placement of the deposits allow for an explanation of the origin of the Urals diamond deposits as the fluid -tectonic mobilization of clay rocks from the buried crusts of weathering k imberlites. (C) 2000 Elsevier Science B.V. All rights reserved.