对内蒙古黄旗海湖心、湖滨2个现代沉积剖面在前期磁组构研究的基础上，进行了沉积物粒度分析。结果显示，2个剖面从下到上都表现出粗颗粒含量逐渐增加的趋势，反映水动力逐渐增强。对比之前的磁组构结果发现，靠近湖心的HQW剖面，粒度与磁组构具有较好的对比性。HQW剖面的磁各向异性度等磁组构参数从下到上表现出逐渐增大的趋势，显示矿物定向和水流流速逐渐增强。另外，在20cm、40cm、65cm深度附近，粒度与磁组构参数都发生突然变化，表明存在水动力增大的异常沉积事件。HQE剖面的磁组构未能有效指示异常沉积事件，但其粒度分析中的细砂百分比含量和中值粒径在这些位置附近明显减小。若这是由同一异常沉积事件造成的，则表明异常沉积事件的沉积过程比较复杂，在研究异常沉积事件时不同的沉积部位需使用不同的研究方法。%Two sections located at the center and lakeshore respectively in the Huangqihai Lake of Inner Mongolia were investigated. In this study, the grain size analysis result was given, which can be regarded as the complement to the previous magnetic fabric study of the sedimentary environment. The result of grain size analysis shows that the particles become coarser upwards in these two sec-tions, indicating increasing hydrodynamic force. A comparative analysis of the grain size and the magnetic fabric reveals that the grain size and the magnetic fabric show evident comparability in the HQW section which is located at the lake center. The magnetic fabric parameter anisotropy degree (P) shows upward increasing tendency, suggesting strong mineral oriented alignment and relatively high hydrodynamic action. In addition, at the depths of about 20cm, 40cm and 65cm, the grain size and the magnetic fabric all display ob-vious change, which further indicates abnormal depositional events with strong kinetic energy. In the HQE section which lies near the lakeshore, the fine-sand proportion and medium diameter grains show obvious decreasing although the magnetic fabric analysis fails to display any abnormal depositional events. If all these phenomena were really caused by abnormal depositional events, the depo-sition process must have been very complex and hence different methods should be employed in studying abnormal depositional events. Because the magnetic fabric is influenced not only by grain size but also by sedimentary structure, it can probably clearly re-veal abnormal depositional events at the lake center, where the hydrodynamic energy is low.
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