Keywords
tectonosphere
density and physical modeling
Section
Abstract
The Chagos-Laccadiv Range is a linear-elongated structure adjacent to the passive margin of western India. The ridge consists of three segments: northern — Lakkadiv ridge, central — Maldives ridge and southern —
bank (archipelago) Chagos. The ridges are separated by depressions and have different manifestations in morphology and anomalous gravitational field. Modeling of the density structure of the Chagos-Lakkadive Ridge tectonosphere showed that the Lakkadive and Maldive segments, most likely, represent submerged blocks of thinned continental crust, partially separated from the continental margin of India by a riftogenic basin. Along with the assumption that the Chagos Bank may contain fragments of the continental crust, the main factor in its formation is apparently the active magmatic activity of the Reunion hot spot, leading to an increase in the thickness of the crust due to underplating. Physical modeling showed that the formation of such a linear structure is possible in the presence of thermal (hot spot) and structural (faults and cracks) inhomogeneities in the model continental lithosphere, which within the continental margin led to a jump (jumping) of the spreading axis towards the young margin and partial separation from it narrow linearly elongated microblocks (ridges).
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