| This paper chose the subtropical region of China as the study area and selected different types of Quaternary Aeolian sediments in different places of this area, such as XiaShu Loess, aggradation red clay, old red sand. Study object includes six typical aggradations red clay sections located in Anhui (FL and XC section), Zhejiang (PF and TX section), Jiangxi (JL section) and Hunan (YJ section), one typical XiaShu Loess section located in Nanjing, Jiangsu (XG section),and two typical Old red sand sections located in Zhejiang (DS section) and Fujian(QF section). Based on the analysis of the particle size and the size frequency curve, to study grain size sensitive component of all kinds of eolian sediments。 In particular, the various types of Aeolian sediment grain size sensitive components of various types of aeolian sediments, primarily between physical relationships discussed. The main results are as follows:(1) There are different granularity sensitive components of different types of Quaternary Aeolian sediments; Xiashu Loess XG profile has three granularity sensitive components, they are component 1 (0.6lμm), component 2 (4.87μm) and component 3 (29.59μm); three components of FL profile are:component 1 (0.60μm), component 2 (5.00μm) and component 3 (22.92μm); three granularity sensitive components of XC profile are:component 1 (0.61μm), component 2 (3.61μm) and component 3 (19.99μm); granularity sensitive components of JL profile are: component 1 (0.94μm) Component 2 (5.34μm) and component 3 (25.8μm); three components of PF profile are:component 1 (0.87μm), component 2 components (11.47μm) and 3 (160.73μm); granularity sensitive components of TX profile are as follows:component 1 (0.56μm), component 2 (2.83μm) and component 3 (13.24μm);the situation of YJ profile is:component 1 (0.59μm), component 2 (4.47μm) and component 3 (17.12μm). Old red sand sections DS and QF profiles has different granularity sensitive components, granularity sensitive components of DS profile as follows:component 1 (0.60μm), components2 (13.02μm).component 3 (213.03μm); granularity sensitive components of QF profile are:component 1 (10.03μm), component 2 (180.66μm); Part 3 (472.65μm).(2) Some similarities exist between the sensitive components of the Quaternary Aeolian Sediments in subtropical; Xiashu Loess XG profile and aggradation red earth section has 3 size fractions, and each grain size group indication is consistent, which indicate the clay component, corresponding weathering; High altitude far source particle fractions, corresponding action of the wind; dust particle group, corresponding to the winter monsoon. Except for the PF profile, due to the influence of near source material and other factors, the clay group was higher than that in other sections, and the average particle of dust particle group size; article size group of old red sand section also has three, corresponding to the clay fraction, dust particle group, saltation components, effect of>63 μm particles by the strong wind is also difficult to be transported for long distance, generally regarded as near source component.(3) The differences between the sensitive components of the Quaternary Aeolian Sediments in subtropical, mainly depending on the distance from the source and spatial location. Based on the comparison of size fractions of each section of the Quaternary Aeolian sediments in the Mid-subtropical zone, Xiashu Loess XG profile and Xuancheng FL and XC wind profile of dust particle group, the average size of from northwest to Southeast smaller trend. Therefore consider there may be a source contact between Xiashu loess and Aggradation red earth, and the East Asian Winter Monsoon to this agreement; Under the action of wind, the DS and QF profile of the old red sand clay components and basic dust particle group, may be brought to the PF and TX profiles, which may cause the clay group PF and TX were higher than those of other sections aggradation red earth profile. JL section of JiuJiang and YJ section also exists difference in latitude, is mainly affected by the impact of the winter monsoon and the distance from Source area. |
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