GeotectonicsGeotectonicsГеотектоника0016-853X3034-4972The Russian Academy of Sciences1564410.31857/S0016-853X201933-24ArticlesСтатьиResearch ArticleStructure and evolution of the Eastern part of the Southwest Indian RidgeСтроение и эволюция восточной части Юго-Западного срединно-океанического Индийского хребтаKokhanA. V.КоханА. В.
Russian Federation
edubinin08@rambler.ruDubininE. P.ДубининЕ. П.
Russian Federation

Museum of Earth Sciences

Музей землеведения

edubinin08@rambler.ruSushchevskayaN. M.СущевскаяН. М.
Russian Federation
edubinin08@rambler.ruLLC SVAROGООО «Сварог»Lomonosov Moscow State UniversityМосковский государственный университет имени М.В. ЛомоносоваVernadsky Institute of Geochemistry and Analytical ChemistryИнститут геохимии и аналитической химии им. В.И. Вернадского РАН1308201943241208201912082019Copyright ©; 2019, Russian academy of sciencesCopyright ©; 2019, Российская академия наук2019Russian academy of sciencesРоссийская академия наукhttps://journals.eco-vector.com/0016-853X/article/view/15644

The structure and evolution of eastern part of the Southwest Indian ridge is discussed. Based on geological-geophysical data and cartographic materials, analysis of spatial and temporal changes of ridge morphostructure was performed. Analysis of the data made it possible to recognize the stages of ridge evolution and delineate its sections differing in tectonics, structure, morphostructural segmentation of the rift zone and the ridge flanks. It is shown that crust in the axial zone of the ridge formed under repeatedly changing spreading kinematics, degree of hotspot activity, and underlying mantle along-axis temperatures. The temporal variations in these characteristics along the rift zone are established, with consideration of their influence on its segmentation and tectonic structural features.

Рассмотрено строение и эволюция восточной части Юго-Западного Индийского хребта. На основании геолого-геофизических данных и картографических материалов проведен анализ пространственно-временного изменения морфоструктур хребта, который позволил определить этапы его эволюции и установить участки, различающиеся особенностями тектоники, строения, морфоструктурной сегментации рифтовой зоны и флангов хребта. Показано, что формирование коры в осевой зоне хребта происходило при многократно менявшихся условиях кинематики спрединга, степени влияния горячих точек и вдольосевого изменения температуры подстилающей мантии. Установлены временны́е изменения этих характеристик вдоль простирания рифтовой зоны и рассмотрено их влияние на ее сегментацию и особенности тектонического строения.

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