蒙脱石氯化钾饱和后的长石化结构——热液循环体系海水潜入区的标志

THE FELDSPARIZED TEXTURE OF POST—MONTMORILLONITE SATURATED WITH KCl—THE MARKS FOR THE DOWNWARD—EXCAVATING SEA WATER CURRENT IN HYDROTHERMAL CYCLIC SYSTEM

林宗南 罗瑞兰

Lin Zongnan Luo Ruilan

地矿部石油地质中心实验室, 无锡 214151

Central Lab. of Petroleum Geology MGMR

蒙脱石氯化钾饱和后,经压实或者加热,会出现长石化,钠蒙脱石向类钾长石转化、钙蒙脱石向斜长石转化。在沉积岩10μm级粘土中,其类钾长石是在海沟-海槽和地堑沉积体系中由钠蒙脱石在高压下成岩转化而成。类钾长石可以作为热液循环体系中海水潜入的地球动力特征标志。 本文发现了类钾长石的存在,在定向的X光衍射XRD图中,3.71A、4.23A和3.3A特征峰的比值为1:1:3.8,这种结构可能是按一定比例的,由类微斜钾长石与低石英组成的复合物,这种物质可能是文象花岗岩的先质。

After the montmorillonites saturated with KCl and experienced through compaction or heatings,feldsparizations would take place,bringing about the transformation of sodium-montmorillonites into iso-potassium feldspars and calcium-montmorillonites into plagio-clases.In the sedimentary rocks with 10μm clay,the iso-potassium feldspar is the product from the sodium-montmorillonites with high pressure in sedimentary system of trench-trough or graben,Therefore,the iso-potassium feldspar can be taken as the marks for the dynamic characters of downward-excavating sea water current in hydrothermal cyclic system.Based on existence of the iso-potassium feldspar,the ratio of the characteristic peak values of 3.71A,4.23A and 3.3A in the oriented X-ray deiffratogram(XRD)is about 1:1:3.8.Such a diffratogram texture may be fixed in a certain ratio and is probable to be the proecursor of graphic granites.

https://doi.org/10.11781/sysydz199204419