Preprints
https://doi.org/10.5194/egusphere-2023-1757
https://doi.org/10.5194/egusphere-2023-1757
25 Aug 2023
 | 25 Aug 2023

Evidence of extension at the southwest continental margin of India and opening of the Laccadive Basin: Constraints from geophysical data

Mathews George Gilbert, Parakkal Unnikrishnan, and Munukutla Radhakrishna

Abstract. Previous geophysical investigations of the Western Continental Margin of India (WCMI) confirm the double breakup history of the margin with the first breakup taking place between India and Madagascar in Late Cretaceous, and the second breakup event in early Paleocene with Seychelles separation from India. Despite numerous geoscientific studies along the WCMI, the southern part of the margin, which is known to be the conjugate segment of the Madagascar, has been least studied. In this study, we evaluate the multi-channel seismic reflection and gravity anomalies at the margin to identify the early rift signatures in conjunction with the magnetic anomaly identifications in the Mascarene Basin. The analysis led to the identification of two extensional directions, a ENE-WSW oriented extension over the Laccadive Ridge north of Tellicherry Arch, and the NW-SE extension in the Laccadive Basin region towards south. Plate reconstruction models of the Mascarene Basin suggest the ENE-WSW extension observed over the Laccadive Ridge could be related to the India-Madagascar separation. However, the sediment deposition pattern and the presence of Paleocene trap associated with the NW-SE extensional grabens observed in the Laccadive Basin region has been attributed to the post-breakup extension between the Laccadive Ridge and the West coast of India. We further propose that the anti-clockwise rotation of India and the passage of the Reunion plume have facilitated the opening of the Laccadive Basin.

Mathews George Gilbert, Parakkal Unnikrishnan, and Munukutla Radhakrishna

Status: final response (author comments only)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on egusphere-2023-1757', Yatheesh Vadakkeyakath, 26 Sep 2023
    • AC1: 'Reply on RC1', Gilbert M George, 13 Dec 2023
  • RC2: 'Comment on egusphere-2023-1757', Anonymous Referee #2, 30 Oct 2023
    • AC2: 'Reply on RC2', Gilbert M George, 13 Dec 2023
Mathews George Gilbert, Parakkal Unnikrishnan, and Munukutla Radhakrishna
Mathews George Gilbert, Parakkal Unnikrishnan, and Munukutla Radhakrishna

Viewed

Total article views: 487 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
344 112 31 487 47 17 19
  • HTML: 344
  • PDF: 112
  • XML: 31
  • Total: 487
  • Supplement: 47
  • BibTeX: 17
  • EndNote: 19
Views and downloads (calculated since 25 Aug 2023)
Cumulative views and downloads (calculated since 25 Aug 2023)

Viewed (geographical distribution)

Total article views: 479 (including HTML, PDF, and XML) Thereof 479 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 20 Apr 2024
Download
Short summary
The study identifies evidence for extension south of Tellicherry Arch along the Southwest Continental Margin of India, through the integrated analysis of multichannel seismic and gravity data. The sediment deposition pattern indicates that this extension occurred after Eocene. We further propose that the anti-clockwise rotation of India and the passage of the Reunion plume have facilitated the opening of the Laccadive Basin.