本文選題：膠狀黃鐵礦 + 新橋礦床��； 參考：《合肥工業(yè)大學(xué)》2017年碩士論文

【摘要】：新橋硫鐵礦床是長江中下游成礦帶銅陵礦集區(qū)內(nèi)層狀、似層狀硫化物礦床的典型代表,長期以來對其成礦作用存在較大爭議。礦床內(nèi)發(fā)育大量順層產(chǎn)出的膠狀黃鐵礦,一方面膠狀黃鐵礦的成因制約了對銅陵礦集區(qū)層狀硫化物礦床成礦作用及機(jī)制的認(rèn)識,另一方面膠狀黃鐵礦晶粒細(xì)小,有可能成為一種重要的納米材料資源。本文利用偏光顯微鏡、粉晶X射線衍射(XRD)、場發(fā)射掃描電鏡(SEM)和高分辨透射電鏡(TEM)等礦物學(xué)研究手段,對新橋礦床內(nèi)膠狀黃鐵礦的成因及納米特性進(jìn)行研究。系統(tǒng)礦物學(xué)研究表明膠狀黃鐵礦為納米-亞微米粒徑的隱晶質(zhì)黃鐵礦,以自形-半自形立方體晶型為主。礦石中含有少量石英及伊利石,呈典型碎屑顆粒形態(tài)。SEM和TEM研究表明膠狀黃鐵礦礦石中仍保存有少量的微生物殘?bào)w和殘留有機(jī)質(zhì)。這些綜合信息反映了新橋膠狀黃鐵礦非巖漿熱液成因,而是生物化學(xué)沉積成因。該層膠狀黃鐵礦由于具有較高的地球化學(xué)活性,在燕山期巖漿熱液的作用下重結(jié)晶顯著,并對成礦熱液形成層狀礦體發(fā)揮了重要的控制作用。作為一種納米礦物,膠狀黃鐵礦的氧化特征有別于普通粗晶黃鐵礦。XRD和SEM分析結(jié)果顯示在自然條件下膠狀黃鐵礦的氧化分為兩個(gè)階段:第一階段主要生成Fe(Ⅱ)硫酸鹽礦物(主要為四水白鐵礬和水綠礬),而第二階段主要生成Fe(Ⅲ)硫酸鹽礦物(主要為板鐵礬和粒鐵礬)。氧化動(dòng)力學(xué)實(shí)驗(yàn)結(jié)果顯示膠狀黃鐵礦在水溶液中的氧化符合零級反應(yīng)模型,氧化速度是粗晶黃鐵礦的36.8倍。這些特征顯示了膠狀黃鐵礦具有較好的納米特性。
[Abstract]:Xinqiao pyrite deposit is a typical representative of layered and stratiform sulfide deposits in Tongling ore concentration area of the middle and lower reaches of the Yangtze River. There are a large number of colloidal pyrite occurring in the ore deposit. On the one hand, the genesis of the colloidal pyrite restricts the understanding of the mineralization and mechanism of the layered sulfide deposit in Tongling ore concentration area, on the other hand, the colloidal pyrite has fine grain size. It is possible to become an important nanomaterial resource. In this paper, the origin and nanometer properties of colloidal pyrite in Xinqiao deposit are studied by means of polarized light microscope, powder X-ray diffraction (XRD), field emission scanning electron microscope (SEM) and high resolution transmission electron microscope (TEM). Systematic mineralogical studies show that the colloidal pyrite is a cryptocrystalline pyrite with nanometer-submicron particle size, mainly in the form of automorphic-semi-automorphic cube. The ores contain a small amount of quartz and Illite, which show typical clastic particle morphology. SEM and TEM studies show that a small amount of microbial residues and residual organic matter are still preserved in the colloidal pyrite ore. These comprehensive information reflect the non-magmatic hydrothermal origin of Xinjiao colloidal pyrite, but the genesis of biochemical deposition. Due to its high geochemical activity, the colloidal pyrite recrystallized significantly under the action of Yanshanian magmatic hydrothermal solution, and played an important role in controlling the formation of stratified orebodies in ore-forming hydrothermal solution. As a nano-mineral, The oxidation characteristics of colloidal pyrite are different from those of crude pyrite and SEM analysis. The results show that the oxidation of colloidal pyrite is divided into two stages under natural conditions: the first stage mainly produces Fe (鈪，

本文編號：1816446