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基于野外考察和14C年代测定, 确定了3 2 ka BP以来念青唐古拉山东部则普冰川的冰进序列.新冰期冰进可明显分为3次: 即大拿[14C(3 242±101)a BP]、大拿顶[14C(1 920±110)~(1 540±85)aBP]和白同[14C(1 056±115)a BP]冰进.新冰期盛时, 则普冰川比现代长 6 9 km, 面积大 17 10 km2,雪线降低约157 m, 温度降低1 0~1 9 ℃. 小冰期可分出2次: 即15世纪或16世纪[14C(580±130)aBP]和19世纪[14C(197±80)a BP, (190±80)a BP]冰进. 小冰期盛时, 则普冰川比现代长 2 0 km, 面积大11 16 km2, 雪线降低约100 m, 温度降低0 65~1 23 ℃. 现代则普冰川, 冰面表碛特别发育, 其厚度亦很大, 冰舌末端退缩难以辨认. 但冰川减薄很强烈, 边缘两侧形成 2~3 道现代侧碛, 并高出现代冰面20~30 m. 对埋藏腐殖质土壤层和木炭碎屑经14C年代测定, 结果表明在(720±210)~(2 010±120)a BP间, 波堆藏布流域存在砍伐森林、开垦田地和放牧的人类活动.
Based on the field investigation and the 14C dating, the ice sequence of the Jibup Glacier in the eastern part of the Nyainqentanglha Mountains since 3 2 ka BP was determined. The ice age of the new glacial period can be obviously divided into 3 times: [14C (3 242 ± 101) a BP], a large [14C (1 920 ± 110) ~ (1 540 ± 85) aBP] and white [14C (1 056 ± 115) a BP] The modern area is 69 km in length with an area of 17 10 km2 and the snow line is reduced by about 157 m and the temperature is decreased by 10 to 19 ° C. The small ice age can be divided into two times: the 15th- or 16th-century [14C (580 ± 130) aBP] And the 19th century [14C (197 ± 80) a BP, (190 ± 80) a BP]). In the mid-Little Ice Age, the general glacier is 20 km long and 1116 km2 wider than the modern one and the snowline is reduced by about 100 m , The temperature decreased 0 65 ~ 1 23 ° C. Hyundai Ze glaciers, ice surface moraine particularly developed, its thickness is also large, the ice tongue at the end retracted illegible.But the glacier thinning is very strong, the edge of the formation of 2 to 3 on both sides Modern side moraine, and higher than the modern ice 20 ~ 30 m. Buried humus soil layer and charcoal debris measured by the 14C, the results show that in the (720 ± 210) ~ (210 ± 120) a BP between the wave reactor Tibetan cloth watershed there deforestation, land reclamation and grazing human activities.