| Реферат: | eng: Conditions of formation of the ultrabasic rocks, which are a part of ophiolite association, draw attention of numerous researchers which, as a whole, can be divided on two basic groups following to the opposite points of view. In one case formation of ultramafic rocks by crystallization of the ultrabasic melts is supposed. Other point of view consists that ophiolite ultrabasites are mantle restites, the refractory rests which resulted melting of a mantle and penetrate into Earth Crust in a solid condition. Our researches of the Kuznetsky Alatau ophiolites have shown that there is no basis to oppose models of a magmatic and metamorphic-deformation origin of ultramafites, because they reflect consecutive evolution of processes of formation of the ultrabasic rocks of ophiolite association. First of all, presence of primary melt inclusions in accessory Cr-spinels from dunites of the Srednetersinsky massive directly testifies to participation of magmatic systems at formation of ultramafites from the Kuznetsky Alatau ophiolites. Study of these inclusions have shown that at the formation of the dunites from the Srednetersinsky massive a high magnasia (mainly picrite) magma (with MgO content nearby 22-30 wt. %) played a great role. Calculating modelling on the basis of the data on melt inclusion composition by means of well-known programs (PETROLOG, COMAGMAT, PLUTON) has allowed to establish following key parameters of magmatogenic processes formation of ultramafic minerals from the Kuznetsky Alatau ophiolites: liquidus crystallization of olivine occurred at temperature 1,550-1,530 degrees C and pressure nearby 6.8-4.3 kbar; crystallization of Cr-spinels from melt - 1,430-1,250 degrees C; solidus of olivine - nearby 1,220 degrees C; possible formation of clinopyroxene from melt - 1,220-1,210 degrees C. With the help of mineralogical thermometers the wide interval of temperatures (since 1,220 degrees C to 1,165 degrees C and further to 730 degrees C) of subsolidus recrystallization was established. This data testifies a difficult (probably long) establishment processes of solid phase equilibrium after crystallization from melts of dunite minerals from the Kuznetsky Alatau ophiolites. According to results of petrostructure analysis follows that ultramafites from the Kuznetsky Alatau ophiolites during of their formation were exposed to repeated deformations in the course of lifting from depths of the top mantle to the consolidation area in the Earth Crust. The general orientation of deformation processes from deep to "near surface" finds reflexion in evolution of petrostructure elements. The conclusions received earlier will be co-ordinated with these representations about sequence of deformations and the mechanism of formation of the unique structural form of the Srednetersinsky ophiolite massive (Kuznetsky Alatau).
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