Mineralogical-geochemical features of contact zone rocks of the Shivey alkaline granite-quartz-syenite and Chadal gabbroic massifs (Eastern Tuva)

9th All Russian petrographic conference with international participation: Petrology of magmatic and metamorphic complexes

Bukharova, O.V.^1 ; Sugorakova, A.M.^2 ; Kadyr-Ool, Ch.O.^2 ; Khertek, A.K.^2

Department of Geology and Geography, Tomsk State University, Lenin Avenue 36, Tomsk

634050, Russia^1

Tuvinian Institute for Exploration of Natural Resources of SB RAS, International Street 117a, Kyzyl

667007, Russia^2

关键词: Altai-Sayan folded area;    Contact zone;    Geochemical analysis;    Geochemical features;    Micro-texture;    Quartz syenite;    Scanning electrons;    X-ray microanalysis;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/110/1/012004/pdf
DOI  :  10.1088/1755-1315/110/1/012004

来源: IOP

【 摘 要 】

The Kaakhem (> 30,000 km2) is one of the major magmatic areal within the Altai-Sayan folded area (Eastern Tuva, Russia). Formations of the Kaakhemsky area were more than 250 million years with change of geotectonic conditions. The last stage is bound to intraplatform magmatism (300 Ma ago). Massifs of bimodal association - gabbroic and alkaline granitoids particularly the Chadal gabbroic and the Shivey alkaline granite-quartz-syenite massifs were formed as a result of its activities within the Kaakhem magmatic areal. The object of the study are rocks breccia-like and drip-like structurs in the contact zone of the alkali-granitoid Shivey and gabbroid Chadal massifs in the Kaakhem magmatic. Predecessors repeatedly noted that such structurs relationships have typical features of mingling: flexuous, scalloped contours of mafic bodies with orientation of protrusions towards granitoids; oval, rounded form of basal fragments; signs of plastic deformation in the basices and others. Geochemical analysis of rare and scattered elements contents in contact zone rocks showed strongly marked character of hybridization. Results of scanning electron microscope analysis and X-ray microanalysis let consider the probable sequence of mineralization in contact zone of massifs of bimodal association of gabbroic and alkaline gran itoids of the Kaakhem magmatic areal. Relationship established between microtexture and geochemical inherity indicate the interaction of basic and granitic magmatic meits and it was formation of middle group rocks.