Abstract
The Karlik Mountains, at the extreme easternmost end of the Tianshan mountain range, mark the terminus of the modern Central Asian Orogenic Belt and serve as a natural laboratory for exploring how strain spreads from the margins of the Eurasian plate to its interior. We investigated Cenozoic strata, including the Oligocene–Miocene Taoshuyuanzi Formation and the Pliocene Putaogou Formation, in the Hami Basin through detailed facies analysis, detrital zircon U–Pb geochronology and magnetic susceptibility to reconstruct the Cenozoic mountain-building history and variations in climate of the easternmost Tianshan range. Provenance analysis indicates that the Cenozoic sediments were derived from the north and can thus be used to reflect the mountain-building processes of the Karlik Mountains. Facies analysis shows that the Taoshuyuanzi Formation began with fan delta deposits at the lake margin, followed by lacustrine deposits, whereas the Putaogou Formation is dominated by alluvial fan deposits. The synchronization with intense aridification, as revealed by sedimentary features, allows us to propose that the coarse-grained alluvial deposition in the Putaogou Formation of the Hami Basin marks the Pliocene uplift of the Karlik Mountains. The magnetic susceptibility increased dramatically in the Pliocene, with the trend correlating well with that of the coarsening lithology. The tectonic uplift of the easternmost Tianshan Mountains, along with the subsequent extreme aridity associated with global cooling and the orogenic barrier, facilitated the preservation of magnetite, leading to the accumulation of alluvial deposits with increased magnetic susceptibility during the Pliocene.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call