An insight into the breakup of Gondwana: Identifying events through low‐temperature thermochronology from the basement rocks of Madagascar

摘要: [1] Fission track analysis was applied to the Precambrian suites of Madagascar in order identify lower-temperature cooling histories and their relationships Phanerozoic events that affected island. Apatite ages range from 431 68 Ma, zircon 452 238 Ma. Thermochronologically, island can be divided into a southern, central, northern region each with subdivision on an east-west basis. The southern is sharply separated central by strongly contrasting apparent apatite over northwest-southeast striking Ranotsara Shear Zone (RSZ). change RSZ indicative later reactivation along younger brittle faults. has oldest diffuse contact third northward. Along entire western margin basement initial Paleozoic exhumation followed heating (burial sediments) during Jurassic Cretaceous times. A decrease eastern 119 Ma coincides predicted positions Marion hot spot after effects erosion are considered. On other hand, these may represent progressive opening southward direction together associated denudation rift shoulder. part remained very stable since at least Devonian times, undergoing only long-term slow rates 1–5 m/Myr.