Volume 7 | Issue 1 | 01J Mari Scie Res Ocean, 2024 Zonal Garnet from Eclogite-Blueschist Complexes - Recorder of the History of their DevelopmentстатьяНаучная хроникаИсследовательская статьяНаучно-популярная статья
Дата последнего поиска статьи во внешних источниках: 5 июня 2024 г.
Аннотация:Garnet has a unique ability to maintain its composition in the situation of changing conditions of metamorphism and fix the chemicalchanges in the new grains, outgrowths and replacements associated with the evolution of mineral formation parameters. Theseproperties and capabilities of garnet were studied by the phase correspondence and mineralogical thermobarometry methodsusing the example of the Maksyutov (Southern Urals) and the Atbashi (South Tien Shan) complexes of crustal mafic eclogites,where they are used as PT indicators of their formation conditions. The issue is considered against the background of solving aspecific petrological problem - the origin in eclogite-blueschist complexes (EBSK) of contrasting series of rocks - high-pressureeclogite blocks, boudins and interlayers in the thickness of a weakly metamorphosed gneiss-schist matrix. In the polymetamorphicMaksyutov complex, the garnet demonstrates complex multidirectional, sometimes inversion zoning, which reflects the featuresof mineral formation at each stage of its development. The corresponding PT trends bear signs of the determining processes ofthe formation of the complex - tectonic melange and coherent development. In the one-stage Atbashi eclogite-blueschist complex,inversion PT trends in the evolution of metamorphism are noted with a turn in their direction clockwise, indicating a transitionfrom a tectonic melange setting to a coherent stage of the terrane dev
