Early Cenozoic rapid flight enigma of the Indian subcontinent resolved: Roles of topographic top loading and subcrustal erosion
|Author(s)||Ramkumar Muthuvairavasamy1, 2, Menier David3, Mathew Manoj3, Santosh M.4, 5, Siddiqui Numair A.6|
|Affiliation(s)||1 : Periyar Univ, Dept Geol, Salem 636011, India.
2 : Univ Teknol Petronas, South East Asia Carbonate Res Lab SEACaRL, Tronoh 31750, Malaysia.
3 : Univ Bretagne Sud, GMGL UMR CNRS 6538, F-56017 Vannes, France.
4 : Univ Adelaide, Dept Earth Sci, Adelaide, SA 5005, Australia.
5 : China Univ Geosci, Sch Earth Sci & Resources, 29 Xueyuan Rd, Beijing 100083, Peoples R China.
6 : Univ Teknol Petronas, Dept Geosci, Tronoh 31750, Malaysia.
|Source||Geoscience Frontiers (1674-9871) (China Univ Geosciences, Beijing), 2017-01 , Vol. 8 , N. 1 , P. 15-23|
|WOS© Times Cited||20|
|Keyword(s)||Geomorphic isostasy, Mantle plume, Continental drift, Plate reorganization, India|
Intrinsic magmatic processes are considered as critical operators of plate movements. Here we demonstrate the role of extrinsic processes consequent to intrinsic processes as a catalyst for anomalous rapid plate movement. The rapid and accelerated flight of the Indian subcontinent since Deccan volcanism until its collision with Eurasia remains as one of the geological conundrums. Data on seismic tomography, peninsular geomorphology and inferences on continuum of subcrustal structures are utilized to address this enigma. We propose geomorphic isostasy as the mechanism that has driven this fastest drift ever recorded in geological history. It was initiated by sudden instability after the Deccan volcanism and resultant extensive accumulation of lava pile over continental lithosphere of northern India, northern-eastern tilt due to crustal thickness heterogeneity and subcrustal thermal stratification. The drift was sustained by Carlsberg and Central Indian ridge-push until collision and sediment top loading at northeast thenceforth. These inferences and geomorphic isostasy as a catalytic mechanism necessitate variability of drift rates as integral inputs for any continental scale modeling.