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选取豫中黄土地区典型的黄土古土壤沉积序列,根据其沉积物中U、Th、K元素的浓度及沉积序列所在地的纬度、经度、海拔对宇宙射线的影响,计算了沉积序列中环境辐射的强度。结果表明:黄土古土壤剖面的平均辐射强度为19.86mGy a-1,变化幅度在21%左右。环境辐射强度在S0、Lt、L1层位中较大,均值分别为20.58、23.19、22.47 mGy a-1。在TS层沉积物中辐射强度最小,平均剂量率为11.35mGy a-1。剂量率值在全新世剖面中的变化分别受到了沉积粉尘物质组成的变化和易淋溶元素迁移的影响。前者对剂量率变化的影响非常微弱;后者的影响则相对较大。Fe/Al值的变化也说明了整个黄土古土壤沉积序列在全新世期间沉积粉尘的物质组成变化非常微弱,指示了全新世近万年尺度内研究区沉积物质是相对较为稳定的。
According to the concentration of U, Th and K in the sediments and the influence of latitude, longitude and altitude on the cosmic ray in the loess area, we selected the typical loess paleosol sequences in the loess area, strength. The results show that the average radiation intensity of the loess paleosol profile is 19.86 mGy a-1, with a variation range of about 21%. The intensity of ambient radiation was larger in the S0, Lt and L1 horizon with mean values of 20.58, 23.19 and 22.47 mGy a-1, respectively. In TS sediments, the radiation intensity was the lowest with an average dose rate of 11.35 mGy a-1. Changes in the dose rate values in the Holocene profile were affected by changes in the composition of sedimentary dusts and the transport of easily leached elements, respectively. The former has a very weak effect on the change of dose rate; the latter has a relatively large impact. The change of Fe / Al value also shows that the composition of sediment dust changed little in the whole loess paleosol sequence during the Holocene, indicating that sediment in the study area is relatively stable in the Holocene over a nearly 10,000-year scale.