【摘要】 对透辉石 钙长石 拉长石 (Di An Ab)三元体系在不同降温速度条件下形成的枝晶进行了研究。其中 ,透辉石枝晶为规则树枝状 ,主枝和分枝明显 ;斜长石枝晶呈放射纤维状集合。枝晶形貌随降温速度变快没有明显变化 ,枝晶晶体结构随降温速度不同而有改变 ,降温速度减小 ,透辉石枝晶晶胞参数a值呈增加趋势 ,b、c呈减小趋势 ,斜长石枝晶b值呈减少趋势 ,c值呈增加趋势 ,两者 β值呈增加趋势 ,但改变不大。随着降温速度增大 ,透辉石枝晶、斜长石枝晶硅氧骨干中 ,铝硅比值增大 ,铝更大程度地替代硅。另外还发现 ,降温越快 ,枝晶结晶数量越少。更多还原

【Abstract】 The dentrites of Di-An-Ab system crystalized at different cooling-rates were studied. Many differences appeared between diopside(Di) dentrites and plagioclase dentrites. Di dentrites look like branches, the other like fibre-gathering. The dentrite morphologies change less at different cooling-rates, while the lattice parameters of dentrites have some changes. When decreasing cooling-rate, the lattice parameters b, c of Di dentrites intend to decrease and a increase, the b value of plagioclase dentrites decrease and c increase. The β values of both dentrites have minor increase with the decrease of cooling-rate. The larger cooling-rate is, the more Al replace Si in of two kinds of dentrites.更多还原