吉林大石头河子地区新生代橄榄玄武岩岩石学和地球化学研究

Petrology and geochemistry of Cenozoic olivine basalt in the Dashitouhezi area of Jilin Province

吉林大石头河子地区新生代橄榄玄武岩为裂隙式喷发火山活动所产出的溢流相橄榄玄武岩,属于钙碱性玄武岩,岩浆来源于软流圈地幔,上升过程中经历了不同程度的橄榄石、单斜辉石的分离结晶作用,但基本未受到地壳物质混染作用影响,形成与滨太平洋板块俯冲引起的松花江断裂再次复活,诱发区域性张裂作用关系密切,构造背景为板内拉张环境。

Cenozoic olivine basalts in Dashitouhezi area, Jilin Province, are overflow facies olivine basalts produced byfissure eruption volcanic activity, belonging to calc-alkaline basalts, whose magma comes from asthenospheric mantle. The magma has undergone the separation and crystallization of olivine and clinopyroxene to varying degrees, but it has not been affected by the contamination of crustal materials. Its formation is closely related to the revival of the Songhuajiang fault caused by the subduction of the littoral Pacific plate and the regional tension. The tectonic setting is the intraplate tension environment.