Continental margin off Western India and Deccan Large Igneous Province

摘要: Massive, transient late syn-rift-to-breakup volcanism during separation between the Seychelles microcontinent and India formed Deccan continental flood basalts their equivalents on Seychelles-Mascarene Plateau conjugate margins, i.e. Large Igneous Province. We estimate an original extrusive area of at least 1.8×106 km2, a volume >1.8×106 km3, suggest plate tectonic model comprising: (1) development microplate by fan-shaped spreading in Mascarene Basin, extension followed A29-27 time. (2) Cessation just after A27 time, along India-Seychelles boundary. (3) Margin subsidence, modified south Goa persistent, time-transgressive effects plume trail. The margin is divided into three regional provinces prolongation transforms which east west boundaries breakup early sea floor spreading. In some aspects, margins are different from other volcanic margins; e.g. wedges seaward dipping reflectors continent-ocean transition have not yet been reported. ascribe this to eruption most voluminous lavas chron 29r, i.e lithosphere syn-rift setting. enigmatic Laxmi Ridge complex marginal high comprised both oceanic crust. It was probably created breakup, but may experienced later magmatic and/or deformation.