Neogene continental climate dynamics prior to the late Miocene uplift of the Northern Tien Shan (Kazakhstan)

在新生代，由于印度与亚洲的碰撞，中亚的大陆环境见证了荒漠化的加剧和季风气候的建立。这些大陆规模的气候变化与山脉的隆起有关，如西藏-喜马拉雅复合体和副特提斯的最终退缩。然而，它们与全球气候演变的相互作用及其时间尚未受到很好的限制，部分原因是缺乏可用的数据。新疆伊犁盆地阿克套山（哈萨克斯坦北方天山）出露的渐新世-中新世层序，因其厚度大、出露条件好，具有研究中亚大陆古气候动态的潜力。我们在此建议对阿克套山进行实地考察，并开展后续实验室工作。我们的目标是记录高分辨率的继承，以便执行（一）基于现代沉积学概念的沉积相的现场评价;（二）记录可能的不连续性;和（三）评估状态的保存palynomorphs。如果我们的勘察工作证明是成功的，计划在今后的提案中应用后续研究。

Continental settings of Central Asia witnessed increased desertification and the establishment of a monsoonal climate during the Cenozoic as a result of India’s collision with Asia. These continental-scale climate shifts are connected to the uplift of mountain ranges such as the Tibetan-Himalaya complex and the final retreat of the Paratethys. However, their interplay with the global climate evolution and their timing is yet poorly constrained, partially because of the paucity of available data. An Oligocene-Miocene succession exposed in the Aktau Hills, Ili Basin (northern Tien Shan, Kazakhstan), has a great potential as an archive for continental paleoclimate dynamics in Central Asia because of its high thickness and excellent exposure. We here propose to carry out a reconnaissance field trip to the Aktau Hills and follow-up laboratory work. Our objective is to document the succession in high resolution in order to perform (i) an on-site evaluation of the sedimentary facies based on modern sedimentological concepts; (ii) to document possible discontinuities; and (iii) to evaluate the state of preservation of palynomorphs. If our reconnaissance work proves successful, follow-up studies are planned to be applied in future proposals.