Abstract
A part of the Ninety East ridge near the equator was examined in 1971 by seismic profiling and gravity and magnetic observations. In the area examined, the topography of the ridge consists of blocklike or en echelon mountainous masses. A fracture zone trending north-south parallel to the overall trend was found along the eastern margin of the ridge topography. This fracture zone probably marks the principal boundary between the central Indian Ocean plate and the Wharton basin plate. The free air gravity anomalies associated with the Ninety East ridge are small, and thus the mass of the ridge must in some way be compensated at depth. The Ninety East ridge may have originated as a result of emplacement of gabbro and serpentinized peridotite beneath normal oceanic crustal layers. The lower density of the gabbro and serpentinized peridotite with respect to normal mantle at equivalent depths provides for both the uplift of the ridge and its compensation at depth.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
