Cretaceous–Cenozoic tectonic events in the western Myanmar (Burma)–Assam region

摘要: Correlation of late Mesozoic mafic and ophiolitic rocks suggests that in the Lower Cretaceous a northeasterly-facing arc was emplaced onto southeast Borneo, western Sumatra, Myanmar (Burma) then 1100 km south its present position, Mogok belt Denqen–Bangong Co ophiolite zone Tibet, all situated on southwestern margin Asia. Reversal tectonic polarity eastward subduction generated magmatic continuation through into Gandise batholith Tibet. Magmatism, interrupted latest Cretaceous, probably resumed Myanmar–Tibet Sumatra segments early Palaeogene. It again Mid-Eocene when an east-vergent nappe overrode Indo-Burman Ranges, deforming Eocene turbidites derived from to east. Following renewed northward ocean floor Eocene, India collided with northern Myanmar, Tibet along suture Jurassic–Triassic flysch adjacent Yarlung ophiolite. In segment arc, crust thickened orogeny underwent extension form metamorphic core complex as west Sagaing Fault moved northward. More than half this movement preceded well-documented 450 post-early Miocene dextral displacement related spreading Andaman Sea. Generation I- S-type granites east either crustal shortening, or more probably, subsequent belt.