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冰芯中所含不溶性微粒与大气粉尘沉降过程密切相关,是重建气候环境变化的良好载体.本文对宁金岗桑冰芯(56m,公元1864～2007年)样品中不溶性微粒进行了系统的岩石磁学研究.结果表明,不溶性微粒的载磁矿物以低矫顽力、准单畴颗粒的磁铁矿为主.在过去的144年中,磁性矿物的粒径无显著变化.但是其含量(饱和等温剩磁指标)变化以～1980年为界,之前变化稳定,之后显著增多.这一现象与青藏高原及北半球的气温变化在大的趋势上具有良好的相似性.我们认为磁性颗粒的增加与气候变暖有着一定的关系.其可能的机制是:在大的时间尺度上,气候变暖导致的冰川退缩和局地气候不稳定使得冰芯中含有磁性矿物的大颗粒物质增多,而与年降水变化相关的沙尘天气频率相关性较弱.因此,青藏高原冰芯不溶性微粒的饱和等温剩磁可能在趋势上反映了气候变暖,为研究该区大气粉尘的沉降过程提供新参数.
The insoluble particles contained in the ice core are closely related to the process of atmospheric dust deposition, which is a good carrier for the reconstruction of climate and environment changes.In this paper, the systematic analysis of the insoluble particles in the sample of Sang Binggang (56m, 1864-2007) The results show that the magnetite minerals with insoluble particles are mainly composed of magnetite with low coercivity and quasi-monodomain particles.The size of magnetic minerals has no significant change in the past 144 years, but its content ( Saturation isothermal remanent magnetization index) changed from 1980 to 1980, and changed steadily before it increased significantly, which is in good agreement with the trend of large temperature over the Tibetan Plateau and northern hemisphere.We consider that the increase of magnetic particles Its possible mechanism is that on a large time scale, the retreat of glaciers caused by climate warming and the instability of the local climate make the large particles containing magnetic minerals in ice cores increase, Therefore, the saturated isothermal remanence of insoluble particles in the ice core of the Qinghai-Tibet Plateau may reflect the warming trend in the trend. Dust settling process of providing new parameters.