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在野外综合考察的基础上,对唐古拉山垭口地区末次冰期的冰碛漂砾(或有冰川擦痕的露头)进行了宇生核素10Be暴露年龄的测定,得到(16.1±1.7)ka BP、(31.9±3.4)ka BP、(41.4±4.3)kaBP和(66.8±4.3)ka BP 4个测年数据.结合前人对本地区研究和测年的资料,确定该区更新世经历了4次较大规模的冰川作用:中更新世晚期的倒数第二次冰期、晚更新世中晚期的末次冰期早冰阶、间冰阶和晚冰阶,依次与MIS6、MIS4、MIS3和MIS2阶段对应;全新世经历了2次小的冰进:新冰期和小冰期,它们的时代与青藏高原其它地区新冰期和小冰期的时代基本一致.末次盛冰期的冰川范围十分有限,并且MIS3阶段的冰进规模远远超过了末次盛冰期.早期考察中所命名的唐古拉冰期和巴斯错冰期的时代是中更新世晚期(MIS6)和末次冰期早冰阶(MIS4),扎加藏布冰期的冰碛可能是末次冰期的冰碛叠加在倒数第二次冰期的冰碛物之上,而又经过后期作用改造而形成的一套冰碛.在该区老的冰碛物上没有测定出MIS6阶段之前的年代数据,可能是由后期的破坏或采集的样品不够充分所致,因此对本区最早冰川作用的时代还有待于进一步深入研究.
On the basis of the comprehensive investigation in the field, the exposure ages of10Be were determined for morass boulders (or outcrops with glaciers) during the last glacial period in the Tanggulashan Pass area, and the (16.1 ± 1.7) ka BP, (31.9 ± 3.4) ka BP, (41.4 ± 4.3) ka BP and (66.8 ± 4.3) ka BP, respectively.According to the data of previous studies and dating in this area, we know that the Pleistocene experienced four times Large-scale glaciation: the last-to-mid-late Pleistocene second-glacial, late-mid-late Pleistocene glaciation, inter-glacial and late-glacial stages correspond to the MIS6, MIS4, MIS3 and MIS2 phases, respectively; The world experienced two small ices: the Neo-Ice Age and the Little Ice Age whose age is basically the same as that of the Neo-Ice Age and the Little Ice Age in other parts of the Qinghai-Tibetan Plateau. The range of glaciers in the last glaciation period was very limited, Far beyond the last glaciation.The tumulus named Tanggula and Buss anomaly named in the earlier study is probably the mid-late Pleistocene (MIS6) and the last glacial (MIS4) glacial moraine The last glacial moraine superimposed the ice in the penultimate glaciation Moraines, and later modi fi ed as a set of moraines, the chronology of the pre-MIS6 period was not determined on the older moraines in the area, possibly due to insufficient post-destruction or insufficient sampling Therefore, the era of the earliest glacier in this area needs to be further studied.