长白山天池碱性熔岩中普遍含有碱性长石斑晶,其端员成分为:Or_(36)Ab_(59)An_(5)。利用魏森堡和旋进照相测出的晶胞参数为;α=8.290,b=12.996,c=7.146,α=91°18′,β=116°02′,γ=90°14′。三斜晶系,C_1~1-P_Υ以费氏台、油浸法和X射线衍射法等手段配合,进行综合研究,结果表明:该碱性长石斑晶应局歪长石,而不是过去人们认为的透长石。 Alkaline feldspar phenocrysts are commonly found in the Tianchi alkaline lavas of Changbai Mountain. Their terminal members are Or_ (36) Ab_ (59) An_ (5). The unit cell parameters measured using Weissenberg and the precession phase are; α = 8.290, b = 12.996, c = 7.146, α = 91 ° 18 ’, β = 116 ° 02’, γ = 90 ° 14 ’. Triclinic system, C_1 ~ 1-P_Y by means of Frauenbaucher, oil immersion and X-ray diffraction methods to conduct a comprehensive study, the results show that: the basic feldspar phenocryst should be crooked feldspar, rather than the past People think of the stone.