The exhumation of the Indo-Burman Ranges, Myanmar

摘要: Abstract The Indo-Burman Ranges (IBR) are a mountain range comprised of Mesozoic-Cenozoic rocks which run the length Western Myanmar, extending into India and Bangladesh; to west lies Indian Ocean, east Central Myanmar Basin (CMB) along Irrawaddy River flows. IBR considered be an accretionary prism, developed at juncture Sunda plates, number hypotheses have been proposed for their evolution. However, in order these evaluated, timing evolution needs determined. We undertook two-pronged approach determining uplift IBR. (1) present first low-temperature thermochronological age elevation profiles using ZFT, AFT ZHe techniques. Our data show: major period exhumation occurred around time Oligo-Miocene boundary; we tentatively suggest, subject further verification, additional or before late Eocene. (2) carried out detailed multi-technique provenance study sedimentary Arakan Coastal region west, compared coeval CMB. determined that during Eocene times, CMB were derived from similar local provenance, arc east. Therefore this there was open connection ocean. By contrast, by Miocene diverged. Rocks deposited through-flowing River, with detritus its upland source Mogok Metamorphic Belt Cretaceous-Paleogene granites north. Such is not recorded IBR, indicating had uplifted time, providing barrier transport material west. To previously published list viable proposals explain range, add new suggestion: boundary could governed change wedge dynamics instigated increase thickness incoming Bengal Fan sediment pile.