The crust below the Indo-Myanmar Ranges of northeast India: A preliminary model in differential isostasy
Keywords:
Tectonics; Ophiolites; Thrust; Depth to detachment; IsostasyAbstract
The sediments of the Indo-Myanmar Ranges of northeast India had been deposited in a subsidence basin open up by rifting nearby the Myanmar continental margin. Thickening of the crust in this belt is due to lateral compression of the basin sediments by overriding continental margin of Myanmar. From the viewpoint of the tectonic setting of the region, the variation in the degree of crustal shortening along the ranges, calculated depth to detachment and supported by petro-geochemical evidences, an evolutionary model of the Indo- Myanmar Ranges Basin has been worked out. Calculating the excess thickness of the crust, a model of the crust below the ranges is constructed using principles of differential isostasy. A narrow strip of detached continental landmass, embedded under the sediments, is predicted in this preliminary study.
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