火山层的对比和源区识别取决于其年龄的相近和成分的相似,然而,一些成分变化较大的火山层,则较难实现火山灰的对比.长白山千年大喷发(公元10世纪中叶)产生的火山灰在俄罗斯远东、朝鲜半岛、日本和格陵兰冰芯等地均有出现,在第四纪环境与火山序列研究领域是一层极为重要的等时对比参考.但是,长白山西侧对于此层火山灰的成分特征有着较大的不一致性,很难实现区域内的对比分析,从而不能作为一个绝对的等时参考.本文对长白山千年大喷发近源的黑色和灰色浮岩中单斜辉石和铁钛氧化物矿物进行成分测试,同时得到了远源四海龙湾沉积物火山灰层中与火山玻璃共生的单斜辉石和铁钛氧化物微晶的成分.结果显示,四海龙湾玛珥湖火山灰具有与千年大喷发黑色浮岩一致的矿物组成,即为普通辉石-透辉石和钛磁铁矿的微晶,与灰色浮岩的富铁钙铁辉石和钛铁矿截然不同,说明四海龙湾中的火山灰应主要来自于千年大喷发黑色浮岩喷发阶段,即为粗面质的喷发阶段,而碱流质的灰色浮岩相关的火山玻璃占少数.本文单斜辉石和铁钛氧化物微晶方法为长白山千年大喷发火山灰对比分析提供了一个新的参考标准. Comparisons of volcanic layers and identification of source areas depend on their age and similarities, however, some volcanic layers with widely varying composition are more difficult to achieve than volcanic ash. The Changbai Mountain millennium eruption (mid-10th century AD) produces Volcanic ash occurs in the Russian Far East, the Korean Peninsula, Japan and Greenland ice cores, and is a very important isochronous reference in Quaternary environmental and volcanic sequence studies. However, the volcanic ash It is difficult to realize the comparative analysis in the region and thus can not be used as an absolute isochronous reference.In this paper, the authors studied the oxidation of clinopyroxene and iron-titanium in black and gray pumice near the Changbai Mountains The results show that the ash of Maer Lake in Four Hailong Bay has the same features with the large-scale eruption of Millenium The consistent mineral composition of black pumice is the crystallite of the pyroxene-diopside and titanomagnetite, rich in iron-rich calcium-iron-pyrrhotite from gray pumice and Iron ore is completely different, indicating that the volcanic ash in Silongwan Bay should come mainly from the black pumice eruption in the Millennium Eruption, which is the eruption stage of the rough substance, while the volcanic glass related to the gray flotation of alkaline fluid substance occupies a minority. The pyroxene and iron-titanium oxide crystallites method provides a new reference for the comparative analysis of the volcanic ash from the Changbai Mountain Millennium Eruption.