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腾冲黑空山粗安岩中含有较多的镁铁质和超镁铁质微型包体,主要为辉长岩类、辉石岩类和极少量的二辉橄榄岩,直径多小于2.5cm.辉长岩类包体具有“开放”结构,常有气孔和基质的贯入,辉石岩类包体以等粒结构和镶嵌结构为特征,它们的矿物成分与熔岩斑晶(斜长石+单斜辉石+斜方辉石)成分相近.辉长岩类和辉石岩类包体平衡温度为1000～1125℃,与熔岩斑晶结晶温度(998～1108℃)基本一致.辉长岩和辉石岩类包体结构和成分均有别于下地壳和幔源包体,应来源于岩浆房内部,其中辉长岩类包体是岩浆上升到岩浆房顶部时结晶作用后形成的晶体-气泡-液体带,而辉石岩类包体则岩浆房底部形成的堆积体.极少量的二辉橄榄岩包体具残斑结构,组成矿物及成分类似于我国东部幔源包体特征,来源于上地幔,由补给岩浆将其带入岩浆房中,并且在岩浆喷发到地表之前可能经受过冷却作用.包体的形成过程反映了岩浆的上升、停留、演化和喷发过程.
There are many mafic and ultramafic micro-inclusions in the black foothills of Tengchong, mainly gabbro, pyroxene and very small amount of lherzolite, the diameter is less than 2.5cm. The peridotectonic inclusions are characterized by an “open ” structure, often with stomatal and matrix inclusions. The pyroxenite inclusions are characterized by a combination of isotopic structures and inlaid structures, and their mineralogical compositions are associated with lavagmatite + Clinopyroxene + orthopyroxene). The equilibrium temperature of gabbro and pyroxenite inclusions is in the range of 1000 ~ 1125 ℃, which is basically consistent with the crystallization temperature of lava (998 ~ 1108 ℃) The structure and composition of the rocks and pyroxene inclusions are different from those of the lower crust and the mantle source, and should originate from the inside of the magma chamber. The gabbro inclusions are formed after the crystallization of magma rises to the top of the magma chamber Crystal-bubble-liquid zone, while pyroxene-type inclusions are the sedimentary bodies formed at the bottom of the magma chamber.A very small amount of lherzorphite inclusions have a residual spot structure, and the compositional minerals and compositions are similar to the features of the mantle-derived inclusions in the eastern China , Originating in the upper mantle, being brought into the magma chamber by the recharge magma, and may have suffered from overcooling before the magma erupted to the surface But the role of the formation of inclusions reflects the magma rising, staying, evolution and eruption process.