Study on Greater Maldive Ridge (GMR)

Recently, researchers traced the tectonic evolution of “Greater Maldive Ridge (GMR)” which is a geodynamic feature in western Indian Ocean.

Key Facts

• The tectonic evolution can help in reconstruct the original Gondwanaland fracture.
• This feature led to present-day configuration of continents, continental fragments, as well as formation of ocean basins in the Indian Ocean.

What did the team find?

The team found that, Maldive Ridge might have formed in close vicinity of Mid-Oceanic Ridge, where new ocean floor is created due to divergent motion of spreading centre or lithospheric plates. They also concluded that, Deep-Sea Channel region (DSC) may probably be oceanic in nature, because of presence of underplated materials associated with hotspot volcanism. Researchers chalked possible geological cross-sections along the GMR, with the help of high-resolution gravity data derived from satellite.

Research team used gravity anomalies to form a three-dimensional picture of variation along the Greater Maldive Ridge and adjoining ocean basins.

State of Gravitational Equilibrium

Study provides the crustal architecture as well as the state of gravitational equilibrium between Earth’s crust and mantle of the GMR segment of larger Chagos-Laccadive Ridge (CLR) system. It was found that, Moho is deeper across Maldive Ridge (MR) segment and shallows southwards in Deep-Sea Channel region (DSC). However, effective elastic thickness values were lower over MR compared in DSC region.

Maldive Ridge

The Maldive Ridge is located in the western Indian Ocean, southwest of India. It is aseismic, that is not associated with earthquake activities. The ridge largely remains uninvestigated. It is of most importance to gain knowledge on structure and geodynamics of such structures. It is a submarine ridge, extends from western shore of Hindustan Peninsula to Arabian-Indian Ridge. It is about 3000 km in length, 200-450 km in width and have the elevation of 2-5 km. Peaks of this ridge rise above the water, to form coral islands (atolls) namely, the Laccadive Islands, Chagos Archipelago and Maldive Islands.