氧化铁对土粒强胶结作用的矿物学证据

DCB脱铁处理高铁土壤前后用NaOH -超声波分散的四个粒级 (<2 μm、2～ 2 0 μm、2 0～ 2 5 0 μm和 2 5 0～2 0 0 0 μm)的矿物组成变化研究表明 :氧化铁对土壤颗粒有很强的胶结能力 ,它可与高岭石、蒙脱石等粘粒矿物胶结形成非常稳定的大颗粒团聚体 ,这些团聚体即使用NaOH -超声波也很难分散

Mineralogical Evidence for Strong Cementation of Soil Particles by Iron Oxides

The minerals of four size separates obtained from two high oxide soils were studied by removing iron oxides with dithionthite-citrate-bicarbonate(DCB),followed by NaOH-ultrasonic dispersion,or directly using NaOH-ultrasonic dispersion.The XRD patterns showed that clay minerals(such as kao1inite?smectite and oxides)were found in significant quantities in sand size separates obtained directly by treating soil with NaOH-ultrasonic dispersion,whereas they were very low in sand size separates after DCB treatment.The difference in mineral compositions of the four separate before and after iron oxide removel demonstrated that iron oxides had very strong cementing capacity and could cement some clay minerals to form very stable aggregates,which were stable to NaOH-ultrasonic dispersion.