Space geodetic test of kinematic models for the Indo-Australian composite plate

The existence of a distinct Capricorn component plate within the composite Indo-Australian plate has previously been questioned. If there is no Capricorn plate, the global positioning system site at Bangalore (on the Indian plate) is predicted to move relative to the Australian plate at a velocity of 10 mm yr−1. If there is a distinct Capricorn plate, Bangalore is predicted to move relative to the Australian plate at a velocity of 17 mm yr−1. Space geodetic data from Australia and India are accurate enough to provide quantitative tests of this prediction and to discriminate between alternative composite plate models. The data best fit a composite plate model that assumes the existence of a distinct Capricorn component plate moving relative to both the Indian and Australian component plates.

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