SPECIFIC FEATURES OF MORPHOSTRUCTURAL SEGMENTATION IN THE RIFT ZONE OF THE SOUTH-EAST INDIAN RIDGE IN THE AREAS OF MANTLE THERMAL ANOMALIES
Abstract
The morphostructural segmentation of the rift zone of the South-East Indian ridge was analyzed at the ridge section between the anomalies with increased (Kerguelen Plume and Amsterdam-St. Paul hotspot) and decreased (Australian-Antarctic discordance) mantle temperatures. To distinguish peculiarities of segmentation the changes of bottom topography of axial and off-axial zones of the ridge were studied using the detailed bathymetric data and the morphostructural schemes were drawn. Results of the study confirm that the changes are probably related to the eastward decrease of mantle temperature. The changes of bottom topography and the rift zone morphostructural segmentation may be caused by the along-axis astenospheric flow and result from the changes of thermal and rheological properties of the axial lithosphere at the increasing distance from the «hot» and the approach to the «cold» mantle anomaly.
About the Authors
A. V. Kokhan
Svarog Ltd.
Russian Federation
Senior Engineer, D.Sc. in Geology and Mineralogy.
Russian Federation
Senior Engineer, D.Sc. in Geology and Mineralogy.
E. P. Dubinin
Lomonosov Moscow State University.
Russian Federation
Museum of Earth Sciences, Sector of Geodynamics, Head of the sector, Professor, D.Sc. in Geology and Mineralogy.
Russian Federation
Museum of Earth Sciences, Sector of Geodynamics, Head of the sector, Professor, D.Sc. in Geology and Mineralogy.
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Review
For citations:
Kokhan A.V., Dubinin E.P. SPECIFIC FEATURES OF MORPHOSTRUCTURAL SEGMENTATION IN THE RIFT ZONE OF THE SOUTH-EAST INDIAN RIDGE IN THE AREAS OF MANTLE THERMAL ANOMALIES. Vestnik Moskovskogo universiteta. Seriya 5, Geografiya. 2017;(6):44-54. (In Russ.)
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