利用XRD,XRF,FT-IR,RS,SEM和DSC分析綦江木化石及围岩

Analysis of Wood Fossils and Surrounding Rocks From Qijiang Region by XRD,XRF,FT-IR,RS,SEM and DSC

采用X射线荧光、X射线衍射、傅里叶红外光谱、激光拉曼光谱、扫描电镜和差热法研究了綦江翠屏山的侏罗纪木化石和围岩的元素组成、矿物结构与基团特征。结果表明:綦江木化石分硅化和钙化两类,钙化类主要含有的元素为钙、铁、铅,硅化类中主要元素为硅、铅,围岩中主要元素为硅、钙、铁、钾、铝;围岩中铝、钛、锶的含量远高于化石,其中铝含量约为钙化类木化石的7倍、硅化类木化石的40倍,钛、锶含量约为钙化类木化石的6倍,说明化石中元素的交代作用具有选择性;硅化类木化石中铅的含量约为围岩中的5倍,说明该树种能富集土壤中的铅,对土壤起到净化作用;綦江钙化类木化石由方解石构成,硅化类木化石由α石英构成。

The element composition, mineral structure and group characteristics of Qijiang wood fossil and its surround-ing rock are analyzed by X-ray Diffraction, X-ray Fluorescence, Fourier Infrared Spectrum, raman spectroscopy, scanningelectron microscopy and differential scanning calorimetry. The results show that the metasomatic forms of wood fossil are con-sisted of two types： silicification and calcification, and calcification characteristic wood fossil are calcium, iron and lead,while the main elements of silicified ones are silicon and lead. The main elements of the surrounding rock are aluminum, cal-cium, iron, potassium and silicon, and the content of aluminum, strontium and titanium in the surrounding rock is muchhigher. The contents of aluminum is about 7 times higher than that of calcified wood fossil and 40 times over that of silicifiedwood fossil, and the content of strontium and titanium is about 6 times that of calcification wood. The metasomatism of ele-ments in the fossils is selective, and the content of lead in wood fossil is about 5 times that of the surrounding rock. It showsthat the trees exhibit enrichment effect and purification effect for the soil. The calcified wood fossil in Qijiang region is com-posed of calcite, while the silicified ones are composed of alpha quartz