The geomorphological features and tectonic evolution in the Northern Seychelles Plateau

doi:10.3969/j.issn.1001-909X.2019.02.003

Abstract

Abstract: Gondwana breakup and the complex rift of Madagascar-Seychelles-India were associated with the formation and evolution of the Seychelles micro-continent and Northern Seychelles Plateau. Based on the high resolution multibeam and gravity data acquired from the China-Seychelles continental margin marine science joint cruise in 2016, high resolution topographic and gravity anomaly map were drew at the first time. Combined with the topography and other geological and geophysical data, the evolution of the Northern Seychelles Plateau was discussed by using the method of the tectonic geomorphology. Here, three narrow ridges and flat abyssal plain which were separated by Amirante Trench from the Seychelles micro-continent were found at the Northern Seychelles Plateau. These ridges extend seaward and apparent discontinuity on topography, which approve that the studying area is an independent tectonic unit that doesn't belong to the Seychelles micro-continent natural extension part. By reviewing the geochemical evidence from the scraping rock samples and plate tectonic evolution history, we suggest that Northern Seychelles Plateau are likely formed during the early expansion phase of the Indian Ocean and the seaward discontinuous ridges are affected by the magma eruption along the transform fault.

Key words: Seychelles Plateau, multibeam topography, tectonic geomorphology, comprehensive geophysical interpretation

CLC Number:

P737.2

SU Ze-guo, TANG Yong, LI He, DONG Yan-hui, FANG Yin-xia, WANG Wei-yang, ZHU Zhi-min. The geomorphological features and tectonic evolution in the Northern Seychelles Plateau[J]. Journal of Marine Sciences, 2019, 37(2): 16-27.

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