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Petrology of late proterozoic volcanics of the ridge Pai-Khoianeva TatyanaInstitute of Geology of the Komi Science Center of the Ural Branch of the Russian Academy of SciencesThe aim of my scientific work is petrological description and indetification of geodynamic conditions of volcanic rocks formation of the ridge Pai-Khoi.Also it is supposed to compare and to find relationship between late proterozoic volcanites of Pai-Khoi and the ridge Ochenyrd.
The following problems were set: detailed petrological and mineralogical characteristics; characteristics of the material composition of rocks; comparison of paleodynamic conditions of volcanic formation Morozov suite in Pai-Khoi and ridge Ochenyrd rocks. The following methods are used:optical microscopy of petrographic samples; the electron microscope analysis of minerals; silicate analysis; geochemical analysis (ICP-MS).
Geological map sheets doneogenovyh formations R-41-XX, XXI, Amderminsk area, JSC "Polyargeo" 1:200 000.
Schematic geological map of the Upper Proterozoic sediments of Amderminsk (by V.V. Tereshko). Note: Amderminsk suite - 17; Morozov suite - 12; Sokolninsk suite - 15 (Timonin et al, 2004).The Riphean - Vendian volcanic complex forms a synclinal structure of the nucleus Amderminsk anticline on the territory of the Pai-Khoi and is its base.
Morozov formation of Late Riphean age (RF3mr) in the northeastern part of the range of Pai -Khoi is represented by various volcanic rocks: volcaniclastic;effusive.
Trachybasalt and lithocrystalloclastic tuffs trachybasalt composition are predominant, lower classes make up the suite.
Trachybasalt serialnoporfirovoy structure and amygdaloidal textureStructure of tuffs trachybasaltic lithocrystalloclastic psephites- psammitic, clastic texture
In the upper section they are replaced by trachyandesite basalt and trachyandesites having fragmentary outputs.
Trachyandesites with pilotaxitic structure microfluidics and texture
Lithocrystalloclastic tuffs rhyodacite composition confined to the upper suites and spread p. Yudesyadyaha
Structure of rhyodacite tuffs lithocrystalloclastic psammitic, clastic texture
Variation diagram of AFM [(Na2O + K2O)-FeO *-MgO] Morozov suite rocks (RF3mr) and ridge Ochenyrd (RF3bd). Border tholeiitic and calc-alkaline series on H. Kuno. Note: Morozov suite (RF3mr): 1 - trachybasalt; 2 - trachyandesite; 3 - trachyandesites; 4 - rhyodacites; 5, 6 - volcanics ridge Ochenyrd.2708-032713-012714-012720-012724-012741-014714-246034605-24613V263202280261166232293238224281Cr13629759,562,923,286594,861,812,597,9Co36,932,72735,714,661,145,330,424,339,6Ni37,848,932,937,321,129543,326,515,743Cu35,7931308695,158,9----Zn816850,876,749,472,611963,775,278,5Ga16,41113,613,312,11317,713,114,714,7Rb2,5411,25,2320,822,3