在大兴安岭的五岔沟地区以及小兴安岭的逊克地区近年来发现了总分布面积达3700平方公里的新生代安山质火山岩。这些火山岩虽然产于大陆板内背景，但是其元素地球化学特征与岛弧高镁安山岩一样，具有高硅高镁，并富集大离子亲石元素，亏损高场强元素等特征，属于罕见的板内高镁安山岩。这些高镁安山岩与碱性玄武岩（钠质和钾质）、拉斑玄武岩共同构成我国东北新生代火山岩家族。通过对这些高镁安山岩系统的野外考察、全岩元素地球化学、Sr-Nd-Pb-Hf放射性成因同位素、Mg稳定同位素和矿物化学分析，结合K-Ar、Ar-Ar年代学分析，了解东北新生代高镁安山岩的时空分布规律及其成因。并探讨这些板内高镁安山岩与该区新生代玄武岩的成因联系，以进一步了解东北新生代岩浆作用的地幔深部背景。

Cenozoic andesitic rocks are recently discovered in Northeast China, covering an area of 3700 square kilometers. Theses rocks are mainly distributed in two places, the Wuchagou area in the Greater Khingan Range and the Xunke area in the Lesser Khingan Range. Although these rocks were generated in intra-plate setting, they show similar geochemical signatures with those of arc high-Mg andesites, e.g. high silicon and magnesium contents, enrichment in large ion lithophile elements and depletion of high field strength elements. Therefore, these unusual intraplate high-Mg andesites, as well as alkaline basalts (both sodic and potassic) and tholeiites, should be regarded as major members of the Cenozoic volcanic rocks in Northeast China. Through whole-rock elemental geochemistry, radiogenic Sr-Nd-Hf-Pb isotopes, stable Mg isotopes, mineral chemistry, K-Ar and Ar-Ar dating, we attempt to understand the temporal and spatial distribution, and the genesis of these high-Mg andesites in Northeast China. Moreover, to further understand the mantle dynamics of Cenozoic magmatism in Northeast China, the genetic link between these high-Mg andesites and the basalts will be investigated.