01-05 December 2025
INCOIS, Hyderabad, India.
| Abstract Submission No. | ABS-06-0022 |
| Title of Abstract | Analysis of Gravity Data Over the Central Indian Ridge Between 3oS and 11oS, Indian Ocean |
| Authors | KIRANMAI SAMUDRALA* |
| Organisation | CSIR-National Geophysical Research Institute |
| Address | Senior Technical Officer, CSS & Gas Hydrates Building, CSIR-NGRI, Uppal Road Hyderabad, Telangana, India Pincode: 500007 E-mail: samudrala.kiranmai@gmail.com |
| Country | India |
| Presentation | Oral |
| Abstract | Detailed gravity investigations using the shipboard gravity data over the Indian Ocean ridges are sparse especially over the slow spreading Central Indian Ridge and Carlsberg Ridge systems. Shipboard gravity and multibeam bathymetry data over a 750 km long section of the Central Indian Ridge has been analysed to understand the crustal structure and the ridge segmentation pattern. Computed mantle Bouguer anomaly (MBA) and residual mantle Bouguer anomaly (RMBA) have shown significant variations along the ridge segments that are separated by transform and non-transform discontinuities. MBA lows have been observed over the linear ridge segments bounded by well-defined transform faults and these are attributed to the thickening of the crust at the middle portions of the ridge segments. The two non-transform discontinuities have shown MBA highs suggesting crustal thinning. MBA and relative RMBA highs have also been observed over the transform faults. The identified megamullion structures have relative MBA highs suggesting thinner crust. The most significant MBA and RMBA highs were observed over the Vema transform fault suggesting anomalously thin crust over the Vema transform fault where the depth reached to 6350 m. Besides the MBA lows along the ridge axis, significant off-axis MBA lows have been noticed suggesting off-axis mantle upwelling zones indicative of thickening of the crust. The rift valley morphologies vary from the typical V shaped valley to the shallow valley floor with undulations on the inner valley floor. Segments with shallow rift valley floor have depicted well defined circular MBA lows with persistent RMBA low, suggesting modulation of the valley floor morphology due to the variation in crustal thickness and the mantle temperature. These are supported by thicker crust and weak mantle lithosphere. |
| Are you part of IIOE-2 endorsed project | no |
| Keywords | Gravity, Central Indian Ridge, mantle Bouguer anomaly, Crustal structure, Segmentation |
| For Awards | yes |
| Date Of Birth | 02-06-1985 |
| ECSN Registration Number | -- |