The massif consist of three main complexes: 1) ultramafic-mafic rocks 2) foidolites 3) alkali granites and syenogranites [Polkanov et al., 1967]. Interpretation of sequence is complicated because of late tectonic and metamorphic processes that are occurred here intensive.
To view the location on the map click here. It is wonderful, you can see faults in granite complex form satellite.
Our object of study were alkaline rocks, particularly alkaline granites. Some authors do not recognize alkaline granite as the product of the same source as for ultramafic and basic alkaline complexes. They consider granites and layered ultramafic-alkaline pluton separately. It is difficult to belive because of emplacement and the similar age (?) of all rocks.
I will not publish our geological schemes because of their incompleteness.
Geological scheme of Gremyakha-Vyrmes massif. Alkaline granites located on the North (elongated crosses). (Kukharenko et al., 1971) |
Granites consist of two alkaline feldspars, quartz, aegirine, arfvedsonite, aenigmatite. They are distinguished from others similar granites by its age, setting and chemistry.
In some old ditches we found uranium-molybdenum occurrence with anomaly high radiation. There is a video demonstrating this.
Materials of prospecting work in 1970's. |
I should say that vegetation covers all the territory and it took a lot for observing outcrops.
Aegirinite. Alkaline metasomatic rock. |
Old prospecting ditch. |