波伏棱(Povlen)型羟基纤蛇纹石的谱学研究

波伏棱型羟基纤蛇纹石是波伏棱型纤蛇纹石矿物的新变种,本文报导它的吸收光谱、红外光谱、穆斯堡尔谱、电子顺磁共振谱和核磁共振谱。 研究表明,吸收光谱是Fe^(3+)和Fe^(2+)的晶场跃迁以及Fe^(2+)→Fe^(3+)的荷移跃迁引起的;红外光谱是OH和Si-O的伸缩振动、OH转动以及Mg-O和Si-O的弯曲振动引起的;穆斯堡尔谱是Fe^(2+)_(八面体)、Fe^(3+)_(八面体)和Fe^(3+)_(四面体)引起的;电子顺磁共振谱是Mn^(2+)_(八面体)、Fe^(3+)_(八面体)和Fe^(3+)_(四面体)引起的;核磁共振谱是管道水,镁八面体和硅氧四面体上的OH引起的;矿物加热到825℃时,结构开始破坏并出现镁橄榄石相。 此外,本文还解释了该蛇纹石颜色的本质,阐明了上述过渡金属离子和OH在该矿物中的结构环境。

前寒武纪含金刚石陆源沉积剖面的主要类型

本文研究了赋存大多数金刚石矿化的前寒武纪沉积杂岩的成份和组构,其目的是为了评价前寒武纪沉积杂岩含金刚石的可能规模。根据对该杂岩组构特点的分析,可以把含金刚石的陆源沉积剖面划分为两个主要类型,这两种类型的形成与不同的构造运动环境有关,并且它们的稳定矿物组份的堆积条件不同。

某地花岗伟晶岩脉和石英碳酸盐脉中褐帘石、独居石形成条件的讨论

The granite pegmatite veins and quartz carbonate veins mentioned in this paper occur in a structurally fractured zone in high-grads Archaean gneiss which corresponds tectonically to an anticlinal axis in a geosynclinal area. The distribution of these veins is prominently controlled by two structural systems striking N 330°--340° W and N 0°--20° E respectively. Allanite, monazite and other rare metal minerals in the veins are related to aegiritization, albitization, microclinization and other alkaline metasomatism, occurring ubiquitously in alkali-metasomatic species and alteration zones. A positive correlation has been found between the rare earth contents of the veins and their K2O/Na2O ratio. During pegmatie and hydrothermal stages, a significant proportion of the rare metals (Ce group) is confined to allanite and etc., while a limited part (Y group) is related to sphene and apatite.