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武尊火山岩下降液相线已被确定下来。矿物组合和斑晶的化学成分随基质(岩浆流体)化学成分的变化而系统地变化。随着基质SiO_2含量的增加结晶顺序如下:在SiO_2含量为53.5～57~*Wt％之间的岩浆中,橄榄石、紫苏辉石、普通辉石、斜长石及磁铁矿共生。SiO_2含量高于57Wt％的液体中橄揽石消失。普通辉石、紫苏辉石、磁铁矿和斜长石继续结晶,直到液体SiO_2的含量至少达到70Wt％。据估计,在分离结晶过程中结晶矿质的量为46Wt％(斜长石22;紫苏辉石6;普通辉石11;磁铁矿7),而岩浆中SiO_2含量的变化从57到70Wt％之间。依据斜长石与其它斑晶的估计比值和肉眼观察的斑晶模式成分比值之间的差值推出了在分离结晶作用过程中斜长石的堆积作用。随着基质SiO_2含量的增加,基质辉石组合依下列顺序变化:普通辉石+易变辉石→易变辉石→易变辉石+紫苏辉石→紫苏辉石。这一变化反映了岩浆标准透辉石含量的减少。分离结晶作用的化学和矿物学特点与日本其它一些岛弧拉斑玄武岩类似,尽管武尊火山的一些岩石标准透辉石含量稍低于其它一些火山的岩石,并且在SiO高于65Wt％的岩石中出现基质紫苏辉石。
Wuzun volcanic rock down the liquidus has been identified. The chemical composition of mineral assemblages and plaques varies systematically as the matrix (magma fluid) chemistry changes. With the increase of matrix SiO 2 content, the crystal order is as follows: In the magma with SiO 2 content of 53.5-57% * Wt%, olivine, peridotite, pyroxene, plagioclase and magnetite coexist. Olivine disappears in the liquid with SiO 2 content higher than 57Wt%. The pyroxene, peridotite, magnetite and plagioclase continue to crystallize until the liquid SiO 2 content reaches at least 70% by weight. It is estimated that the amount of crystalline mineral in the separation crystallization is 46 Wt% (plagioclase 22; peridotite 6; pyroxene 11; magnetite 7), while the change in SiO 2 content in the magma ranges from 57 to 70 wt% between. Based on the difference between the estimated ratio of plagioclase and other phenocrysts and the macroscopically observed ratio of plagioclase modes, the plagioclase accumulation during detachment crystallization was introduced. With the increase of matrix SiO 2 content, the matrix pyroxene assemblages changed in the following order: normal pyroxene + palygorskite → feldspathite → feldspathic periclase + peridotesterite → peridotite. This change reflects the reduction of magmatic diopside. The chemical and mineralogical characteristics of segregation are similar to those of some other island arc tholei basalts in Japan, although some of the rocks in the Mt.Mujen volcano have a slightly lower diopside content than some other volcanic rocks, and in rocks with SiO higher than 65Wt% In the matrix of perilites.