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对关中盆地东部全新世黄土-古土壤序列(YHC剖面)常量元素分析,发现:YHC剖面化学组成以SiO2、Al2O3和CaO为主,三者平均含量的总和达774.1g.kg-1,元素含量SiO2>Al2O3>CaO>Fe2O3>MgO>Na2O>K2OTiO2;相对黄土L1,Ca、Na、Mg在S0中相对迁移,且Ca、Na淋溶强烈,K、Fe、Al在S0中相对轻微富集;关中平原东部风化程度弱,处于较弱的脱Ca、Na初级风化阶段(并且可能在沉积源区就已经发生),伴有碳酸盐的淋溶。CIA等揭示的YHC剖面各层的风化顺序S0>Lt>L0>TS>L1UCC,与关中西部扶风和黄土高原中部庄浪相比,关中平原东部的风化程度居中。CIA对气候的响应灵敏,揭示出早全新世风化渐强气候变暖,中全新世风化最强气候暖湿,晚全新世以来风化程度骤然减弱气候恶化,对次一级的气候事件也有反映。
The analysis of the elemental composition of the Holocene loess-paleosol sequence (YHC profile) in the eastern Guanzhong Basin shows that the chemical composition of the YHC profile is dominated by SiO2, Al2O3 and CaO. The average content of these three elements amounts to 774.1 g.kg-1. SiO 2> Al 2 O 3> CaO> Fe 2 O 3> MgO> Na 2 O> K 2 O x TiO 2; relative loess L1, Ca, Na and Mg migrate relatively in S0 with strong leaching of Ca and Na; relatively mild enrichment of K, Fe and Al in S0 In the east of the Guanzhong Plain weathered to a weaker degree and weakened from the primary weathering stage of Ca and Na (and probably already occurred in the sedimentary source region), accompanied by leaching of carbonate. The weathering sequence S0> Lt> L0> TS> L1UCC of each layer of YHC profile revealed by CIA shows that the weathering degree in the eastern Guanzhong Plain is the same as that of Zhuangzhong in the middle part of the Guanzhong Plain and the middle part of the Loess Plateau. The sensitivity of the CIA to the climate reveals that the early Holocene weathering became warmer and warmer. The mid-Holocene climate was warmer and wetter. Since the late Holocene, weathering has been abruptly weakened and climate change has been reflected in the sub-level climate events.