The role of the Andaman Nicobar fault (ANF) in shaping Narcondam offshore: Insights from high-resolution reflection seismic data

The study investigates the Andaman Nicobar Fault (ANF) and its role in the evolution of a volcano-supported basin adjacent to Narcondam Island, using three high-resolution 2D seismic reflection profiles. Migrated images show a fluid zone, determined through velocity and polarity analyses, with mean 1/Q values ranging from 0.0165 to 0.0096 for Lines 1 to 3. Additionally, polygonal faults are imaged, with varying thicknesses (0.1–0.4 km) of Miocene age, positioned above the fluid saturated zone. The migrated sections further show the branches of the ANF to be conduits for fluid migration and accumulation within the basinal deposits. The study finally highlights a shift in depocenter during the Neogene period, indicating fluctuations in sediment supply from the Irrawaddy River and the evolution of the ANF branch. © 2024 Elsevier Ltd