jvanne
Siilinjärvi Open Pit
The Siilinjärvi carbonatite complex consists of a steeply dipping lenticular body roughly 16 km long with a maximum width of 1.5 km intruded into granite gneiss. The main rock types are: calcite carbonatite, phlogopite carbonatite, glimmerite and their apatite-bearing varieties. The fenite halo is represented mainly by quartz-aegirine syenite. Crosscuting the bedrock, the halo, and main body is a 4 km long, 20-30 m wide, melasyenite dike related to the same intrusive event as the carbonatite.
U-Pb zircon and baddeleyite age determinations yield a weighted mean age of 2610 Ma for the Siilinjärvi carbonatite (D. Zozulya, T. Bayanova, N. Eby, K. Kullerud, E.K. Ravna).
See also: National Land Survey of Finland
Siilinjärvi Open Pit
The Siilinjärvi carbonatite complex consists of a steeply dipping lenticular body roughly 16 km long with a maximum width of 1.5 km intruded into granite gneiss. The main rock types are: calcite carbonatite, phlogopite carbonatite, glimmerite and their apatite-bearing varieties. The fenite halo is represented mainly by quartz-aegirine syenite. Crosscuting the bedrock, the halo, and main body is a 4 km long, 20-30 m wide, melasyenite dike related to the same intrusive event as the carbonatite.
U-Pb zircon and baddeleyite age determinations yield a weighted mean age of 2610 Ma for the Siilinjärvi carbonatite (D. Zozulya, T. Bayanova, N. Eby, K. Kullerud, E.K. Ravna).
See also: National Land Survey of Finland