Geochemicalstudyofboronisotopesintheprocessofloess

来源 :Science in China(Series D:Earth Sciences) | 被引量 : 0次 | 上传用户:yellowerriver
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In this paper the boron contents and boron isotopic composition of acid-soluble phases in loess and paleosol samples are determined for the first time. The boron contents of acid-soluble phases in the Luochuan loess section (S0 S2) vary within the range of (0.8—2.7)?0-6 and their d 11B values vary from 1.8?to +18.6? mostly within the range of 0—+10? The boron contents and d 11B values of paleosol layers are higher than those of loess layers, especially in the loess layer S1. Varying chemical weathering intensity and loess adsorption capability are the main fac-tors leading to the variations of boron contents and d 11B values of acid-soluble phases in the loess section. The variation of chemical weathering intensity in response to the variation of climatic con-ditions seems to be the main factor leading to the variations of boron contents andδ11B values of acid-soluble phases in the loess section. In this paper the boron content and boron isotopic composition of acid-soluble phases in loess and paleosol samples are determined for the first time. The boron contents of acid-soluble phases in the Luochuan loess section (SO2) vary within the range of ( 0.8-2.7)? 0-6 and their d 11B values ​​vary from 1.8? To +18.6? Mostly within the range of 0- + 10? The boron contents and d 11B values ​​of paleosol layers are higher than those of loess layers, especially in the loess layer S1. Varying chemical weathering intensity and loess adsorption capability are the main fac-tors leading to the variations of boron contents and d 11B values ​​of acid-soluble phases in the loess section. The variation of chemical weathering intensity in response to the variation of climatic con-ditions seems to be the main factor leading to the variations of boron contents and δ11B values ​​of acid-soluble phases in the loess section.
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