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对罗布泊典型地区表层土磁性特征、粒度及地球化学特征的研究表明:(1)总体样品磁性矿物含量均较低;各样地间磁化率差异较为明显,阿奇克谷地西部磁化率值最高(2.1×10-7 m3·kg-1),耳轮区最低(0.47×10-7 m3·kg-1),该区磁化率值总体表现为东部略高于西部。(2)样品粒度组分总体以粉砂(2~63μm)为主,平均约占74.17%,分选性较差,细颗粒占主导地位,且各粒度组分之间的含量变化幅度较小。(3)易溶性盐主要是由Cl-、SO2-4、Na+和K+构成,Mg2+、Ca2+含量较低,HCO-3、CO2-3含量很低,易溶性盐类型主要为Cl--SO2-4-Na+和K+型;样品总有机碳平均含量约为0.66%;pH值变化范围为6.98~8.00,且耳轮区样品值均高于阿奇克谷地西部。综上所述,该区当时气候已转向干旱化趋势发展,而且气候持续干化与补给变化对该区物质形成具有一定影响,是该区物质空间分布的主要成因。
The magnetic properties, grain size and geochemical characteristics of the topsoil in the Lop Nur area show that: (1) the overall content of magnetic minerals is low; the magnetic susceptibility varies significantly among the various plots; and the magnetic susceptibility in the western Aqq Valley is the highest ( 2.1 × 10-7m3 · kg-1), and the lowest in the helix region (0.47 × 10-7m3 · kg-1). The overall magnetic susceptibility values in this area are slightly higher in the eastern part than in the western part. (2) The particle size of the sample is mainly composed of silt (2 ~ 63μm), accounting for an average of 74.17%, the sorting is poor, the fine particles dominates, and the variation of the content between the various particle size components is small . (3) The soluble salts are mainly composed of Cl-, SO2-4, Na + and K +, while the contents of Mg2 + and Ca2 + are lower, the contents of HCO-3 and CO2-3 are lower, and the soluble salts are mainly Cl - SO2- 4-Na + and K +. The average content of total organic carbon in the sample was about 0.66%. The pH ranged from 6.98 to 8.00. To sum up, the climate of the area turned to the trend of aridification at that time, and the effects of continuous climate change and recharge on the material formation in this area are the main causes of the material spatial distribution in this area.