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通过ESR和14C测年对典型冰碛物进行直接和间接定年,并结合冰碛地貌形态和位置,确定稻城冰帽区自中更新世以来经历了6次较大规模的冰川前进,依次与MIS 16、MIS 6、MIS 3中期、MIS 2早期、全球意义上的末次盛冰期(MIS 2)和冰后期对应,冰川作用规模基本上逐渐减小.最早、规模最大的冰川作用发生在570kaBP前后,意味着本段高原面在570kaBP之前已进入了冰冻圈,且自那时起,该区经历了较大规模的抬升作用.全新世到来之前,稻城冰帽全部消失了,它是一个随着气候冷暖波动逐渐后退的过程,不是以死冰的方式突然消亡.值得注意的是,末次冰期大间冰阶中期(MIS 3b)的冰川前进规模超过了末次盛冰期(MIS 2),表明末次冰期最盛期在全球范围内的不同步性.其不同步的原因可能是:MIS 3中期,北半球夏季太阳辐射相对较低,但其海陆分布状况能够诱发较强的南亚夏季风,它给以季风降水为主要补给的海洋性冰川区带来较多的降水,结合该时段较低的温度,有利于冰川较大规模前进;末次盛冰期时,气候严寒,但夏季风微弱,降水稀少,冰川平衡线下降程度反而不及MIS 3b.
Through direct and indirect dating of typical moraines by ESR and 14C dating, combined with the morphology and location of the moraine, it has been determined that the ice cap area of Daocheng has undergone six large-scale glacier advances since the Middle Pleistocene, followed by MIS The scale of glacier action gradually decreased in the middle period of MIS6, MIS3, MIS2 in the early MIS2 and the late ice age, and the earliest and largest glacier occurred before and after 570kaBP, Means that the plateau of this segment had entered the cryosphere before 570 kaBP, and since then the area experienced a large-scale uplift, and before the Holocene, the in-the-ice cap disappeared completely, It is noteworthy that the scale of the glacier in MIS 3b during the last ice age exceeded that of the last glacial ice age (MIS 2), indicating that the temperature in the last glacial period was the highest The reasons for this non-synchronization may be as follows: Mid-MIS3 in the northern hemisphere summer relatively low solar radiation, but the distribution of land and sea can induce a strong South Asian summer monsoon, which gives a monsoon drop In the last ice age, the climate was cold, but the summer monsoon was weak, the precipitation was scarce, and the glacier balance line The extent of decline is less than MIS 3b.