Meta surface-Assisted Electromagnetic and Magnetic Characterization of Tectonic Elements and Intraplate Deformation in the Central Indian Ocean Basin

<title>Abstract</title> <p>The Central Indian Ocean Basin (CIOB) south of Sri Lanka is a highly complex area of the Indian Ocean that contains a variety of structural features such as aseismic ridges, fracture zones, hotspot volcanic activity, intraplate deformation, and many different interactions along plate boundaries. The purpose of this study is to analyse marine Meta surface-Assisted Electromagnetic and magnetic anomalies located between 6°N and 6°S latitude and 77°E and 90°E longitude and to present interpretations on these magnetic anomalies using integrated methods applied to the EMAG-2 dataset. The processing applied includes horizontal and vertical derivative analysis, upward and downward continuation of the surface, analytical signal processing, tilt derivative (TDR), horizontal gradient of TDR (HG-TDR), and reduction to the pole (RTP). The results of processing show that the magnetic anomalies identified range from − 116 to 92 nT and were used to interpret the various tectonic features such as the Ninety East Ridge (NER), 85°E Ridge, Comorin Ridge, Afanasy Nikitin Seamount (ANS), Indrani and Indira Fracture Zones. The analytical signal and RTP techniques defined the volcanic basement of the NER and ANS as highly magnetic, while the horizontal derivatives and TDR techniques identified sharp tectonic fabrics and basement discontinuities along with the fracture zones. The use of upward continuation illustrates deep crustal architectures and anomalies related to hotspots, while downward continuation illustrates shallow intrusions and uplifted basements. Overall, the results presented in this study indicate that the CIOB south of Sri Lanka is being influenced by the interaction of ridge-fracture zone systems, magnetically influenced volcanic basement, lithospheric flexure, and tectonic reactivation due to continued intraplate deformation.</p>