月球及火星科学中的三个矿物学问题

发布时间：2018-06-02 00:32

本文选题：叶绿矾 + 高铁硫酸盐　；参考：《山东大学》2011年博士论文

【摘要】：行星科学是一门综合科学,它利用物理、化学以及地质等多种科学手段研究行星、卫星、以及行星系统的各种性质。而人们通常讲的行星科学主要以我们所在的太阳系的天体作为研究对象。行星科学的历史可以追溯到希腊的哲学家Democritus。然而行星科学领域出现具有实际意义的进步是17世纪人类发明了望远镜,这以后人们通过望远镜发现了太阳系的大部分行星。基于科技发展,人们终于在上世纪50年代开始进入了深空探测的新时代,人们进行了包括对月球、火星、金星、水星、冥王星以及土卫六等的非常多的深空探测任务。这些深空探测任务使人们得到了比地基望远镜所得到的更精确的大量行星数据,使人们更进一步了解了我们地球周围的天体。最近的十年,包括我国在内的很多国家都展示了它们对探索外太空天体(例如火星、月球以及其他天体等)的兴趣。而本论文的工作中所涉及的月球返回样品和火星相关矿物的三个研究工作则属于行星科学领域中具有重要意义的基础科学研究部分。第一个课题是对火星上很有可能出现的叶绿矾族矿物的光谱学研究。第二个课题则属于对火星上观测到的含水高铁硫酸盐的相图的研究。第三个课题是研究两种阿波罗返回月壤中的钛含量分布。火星探测车(Mars Exploration Rovers)和火星侦查者号轨道探测器(Mars Reconnaissance Orbiter)都在火星上观测到了铁硫酸盐,这使得在实验室中研究铁硫酸盐在火星表面类似条件下的性质变得十分重要。而叶绿矾族矿物是火星表面或者表面浅层可能存在的铁硫酸盐矿物之一,因此研究它的光谱学性质特别是其光谱在有阳离子替代情况下的变化将会非常有意义。我们在实验室里合成了四种具有不同阳离子替换的叶绿矾族产物,它们分别是高铁叶绿矾、叶绿矾、镁代叶绿矾以及铝代叶绿矾。我们用X射线衍射的方法对所合成的物质的物相进行了鉴别并确认了其纯度。我们选择性的对合成的样品采集了喇曼光谱、中红外光谱、可见近红外光谱以及LIBS光谱。我们选择使用的这些技术正在或者将要被应用在火星探测中。我们在所采集的喇曼光谱中发现了四种样品的硫酸根的v1喇曼峰位随着阳离子替换发生了有规律的变化。在LIBS光谱的研究中,我们发现光谱所展示的样品中阳离子含量的相对比值与样品本应该具有的比值是相洽的。在研究样品X射线衍射谱的时候,我们发现叶绿矾族矿物的光谱中的三个最强的X衍射谱线的位置发生了有规律的变化,这种变化显示由于阳离子替换导致了叶绿矾族矿物晶体结构发生了规律的变化。而在四种样品的中红外光谱中,我们发现了一个很强的硫酸根的v,峰,这表明了由于叶绿矾族矿物本身晶体结构中的硫酸根基团很低的晶位对称性引起了硫酸根本身对称性的改变,从而导致了选择定则的破坏。和具有二价阳离子的叶绿矾族矿物相比较,具有三价阳离子的叶绿矾族矿物不仅具有叶绿矾族共有的两个近红外波段分别在1.4以及1.9微米附近的两个很强的吸收峰外,还在2微米附近出现了两个额外的小的吸收峰。在可见近红外光谱中,有一个电子跃迁谱产生的吸收峰的峰位由高铁叶绿矾的850纳米左右偏移到了叶绿矾的866纳米左右,这种偏移很有可能是由叶绿矶矿物中的亚铁离子出现在900纳米附近的电子跃迁吸收峰与850纳米的吸收峰叠加导致的。人们最近在火星表面发现了各种不同的高铁硫酸盐,这使得在与火星表面温度相关的温度条件下研究高铁硫酸盐的各种基础性质(稳定场、相图、相变路径和反应速率)变得更加有意义。在本论文的工作中,我们利用湿度控制器技术、重量测量技术以及喇曼光谱学技术确定了五水铁矾和七水铁矾在一个标准大气压下的相图边界上的两个实验点,然后我们对两个实验点进行了热力学分析并得到了五水铁矾和七水铁矾之间相变的热力学参数。基于这些热力学参数,我们又推得了五水铁矾和七水铁矾相图边界上在两实验点之间的所有点。我们对所得的实验结果做的热力学分析显示在五水铁矾和七水铁矾相变的过程中每一个水分子结晶相应的反应物的焓的变化是-290.773±0.3447kJ/mol,而相应的吉布斯自由能的变化为-238.81±0.0219kJ/mol。这些结果与其他研究者的估计结果相符。遥感光谱紫外-可见反射率比值是月球表面Ti元素含量(TiO2)估算中广泛应用的一个参数,目前,人们试图通过正在运行的月球观察者号(Lunar Reconnaissance Orbiter)航天器上所搭载的宽角相机(Wide Angle Camera)完成月全球Ti含量分布的测量(利用321纳米以及360纳米两个波段)。为了更好的理解遥感光谱紫外-可见反射率比值与Ti含量之间的关系,我们在实验室中利用一种复合的数字图像方法(结合了反射电子图像和X射线图像)对月球返回样品元素含量作了定量的分析。在此研究中,我们列出了两种富含钛元素月壤中钛元素的分布。这两种月壤分别是阿波罗11返回的样品10084和阿波罗17返回的样品71501。在这两种富钛月壤中,占主导地位的铁钛氧化物为钛铁矿,其他相关的矿物很少见(如阿姆阿尔柯尔矿、钛尖晶石或者金红石等)。在两种月壤中,粘连物和角砾岩的体积含量都随着月壤粒径的减小而减少。但是,单矿物月壤颗粒所占的体积比例则随着月壤粒径的减小而增加。这种现象可以用多相共生的角砾岩碎裂为更小、单相的月壤颗粒来解释。在相对更成熟的月壤10084中,更多的钛元素存在于玄武岩中的较小的钛铁矿颗粒中。而在亚成熟的月壤71501中,更多的钛元素分布于较大的单相钛铁矿颗粒中。这种不同可能反映了两种月壤中钛铁矿的起源矿物的性质不同。我们没有发现Ti元素的分布随着月壤颗粒大小的改变而改变,然而我们却发现月壤10084中钛铁矿颗粒的形状随之有较小的变化。在分析火星轨道或者登陆探测器光谱仪所得到的光谱时,我们在实验室中观测到的叶绿矾族矿物的各种光谱特征可以帮助鉴别出火星上有可能存在的叶绿矾族矿物。而我们观测到的不同叶绿矾族矿物之间的光谱特征的差别甚至可以进一步帮助鉴别火星上叶绿矾族矿物的详细种类。在研究铁硫酸盐相图的工作中,我们建立了一套比较完整的研究含水铁硫酸盐相图的方法。我们得到的铁硫酸盐的热力学参数和它们的相图边界可以帮助我们更好的理解铁硫酸在火星的起源、演化以及分布。我们将把所得到的两种典型月壤中Ti的分布的数据与这些月壤的紫外、可见光谱作比较,从而更好地理解月壤紫外、可见光谱强度与月壤中的Ti含量、含Ti矿物、以及钛铁矿形状等因素之间的关系。
[Abstract]:Planetary science is a comprehensive science that uses a variety of scientific means, such as physics, chemistry, and geology, to study the various properties of planets, satellites, and planetary systems. The planetary science, which is generally spoken, mainly uses the celestial bodies in our solar system. The history of planetary science can be traced to the Greek philosopher Democrit. Us. however, a practical progress in the field of planetary science was the discovery of a telescope in seventeenth Century. After that, people discovered most of the planets in the solar system. Based on the development of science and technology, people began to enter the new generation of deep space exploration in the 50s of last century. People have included the moon, Mars, and Venus. Mercury, Pluto, and the very many deep space exploration missions, such as earth guard six. These deep space missions have enabled people to get more accurate data from the foundation telescope and make people know more about the celestial bodies around us. In the last ten years, many countries including China have shown them. Exploring the interest of outer space objects such as Mars, the moon and other celestial bodies, and the three research work on the return of the moon and the minerals associated with Mars in this paper is part of the fundamental scientific research in the field of planetary science. The first is a very likely leaf on Mars. The second subject is a study of the phase diagram of hydrous high iron sulfate observed on Mars. The third subject is to study the distribution of titanium in the two species of Apollo's lunar regolith.
The Mars Exploration Rovers and the Mars Reconnaissance Orbiter (Mars Reconnaissance Orbiter) all observed iron sulphates on Mars, making it important to study the properties of iron sulphate in similar conditions on the surface of Mars in the laboratory, and the green alum mineral is the surface of Mars or the superficial layer. One of the possible iron sulphate minerals is possible, so the study of its spectroscopic properties, especially in the presence of cation substitution, will be significant. We have synthesized four species of green alum products with different cation substitutions in the laboratory, which are high iron leaf green alum, leaf green alum, magnesium substitute green alum, and We used X ray diffraction to identify the phase of the synthesized material and confirm its purity. We selectively collected Raman, mid infrared, and LIBS spectra for the synthesized samples. The techniques we choose to use are or will be applied to Mars exploration. In the Raman spectra we found that the V1 Raman peak of the sulfate radical of four samples has changed regularly with the cation substitution. In the study of the LIBS spectrum, we found that the relative ratio of the cation content in the samples displayed in the spectrum is consistent with the ratio of the sample which should have been supposed to have. In the study of the sample X At the time of ray diffraction, we found that the position of the three strongest X diffraction lines in the spectrum of green alum minerals has changed regularly. This change shows that the crystal structure of the green alum mineral has changed regularly due to cation substitution. In the mid infrared spectrum of the four samples, we found one. The V, peak of the strong sulfate radical shows that the symmetry of the sulfate radical is caused by the low crystal position symmetry of the sulfate radical group in the crystal structure of the leaf green alum mineral itself, which leads to the destruction of the selection rule. Compared with the two valence cations, the leaf green alum family with trivalent cations Minerals not only have two very strong absorption peaks in two near infrared bands, which are near 1.4 and 1.9 microns, respectively, and there are two additional small absorption peaks in the vicinity of 2 microns. In the near infrared spectrum, there is a peak of the absorption peak of an electronic transition spectrum from 850 nanometers of high iron leaf green alum. The offset is about 866 nanometers of leaf chlorosunite, which is likely to be caused by the superposition of the electron transition absorption peaks in the vicinity of 900 nanometers and the absorption peak of 850 nanometers by the ferrous ions in the chlorophylla.
Different kinds of high iron sulphates have been discovered recently on the surface of Mars, which makes it more meaningful to study the basic properties of high iron sulfate (stable field, phase diagram, phase transition path and reaction rate) at temperature related to the surface temperature of Mars. In this paper, we use humidity controller technology, weight The measurement and Raman spectroscopy techniques determine the two experimental points on the boundary of the phase diagram of five ferric alum and seven ferric alum at a standard atmospheric pressure. Then we analyze the thermodynamic parameters of the two experimental points and obtain the thermodynamic parameters of the phase transition between five vitriol and seven ferric alum. Based on these thermodynamic parameters, we All points on the boundary between the five ferric alum and the seven ferric alum phase diagram on the boundary between the two experimental points are also pushed. The thermodynamic analysis of the results obtained shows that the enthalpy of the corresponding reactant of each water molecule during the phase transition of five ferric alum and seven ferric alum is -290.773 + 0.3447kJ/mol, and the corresponding Gibbs The change of free energy is -238.81 + 0.0219kJ/mol.. These results are consistent with the estimation results of other researchers.
The ultraviolet visible reflectance ratio of remote sensing spectrum is a parameter widely used in the estimation of the Ti element content (TiO2) on the surface of the moon. At present, people are trying to measure the monthly global Ti content distribution by the wide angle camera (Wide Angle Camera) on the running lunar observer (Lunar Reconnaissance Orbiter) spacecraft. With 321 nanometers and 360 nanometers two bands. In order to better understand the relationship between the ratio of the ultraviolet visible reflectance and the Ti content of the remote sensing spectrum, we used a complex digital image method (combining the reflected electronic image and X ray image) to make a quantitative analysis of the content of the elements in the return samples of the moon. In the study, we listed the distribution of titanium elements in two kinds of lunar soils rich in titanium. The two lunar soils were respectively Apollo 11 returned samples 10084 and Apollo 17 returned in 71501. of the two rich Ti rich lunar soils. The dominant titanium oxide was ilmenite, and other related minerals were rare (such as Amal Karl ore, titanium tip. The volume content of adhesions and breccia decreases with the decrease of the size of lunar soil in two lunar soils. However, the volume proportion of single mineral lunar soil increases with the decrease of the size of the lunar soil. This phenomenon can be solved by the fragmentation of polyphase conglomerate to smaller, monophasic lunar soil particles. In the relatively mature lunar 10084, more titanium elements are found in the smaller ilmenite particles in the basalt, and in the submature lunar 71501, more titanium elements are distributed in the larger monophasite particles. This difference may reflect the different properties of the origin of the ilmenite in the two months of soil. It was found that the distribution of Ti elements changed with the size of lunar soil particles. However, we found that the shape of ilmenite particles in lunar soil 10084 changed slightly.
In the analysis of the spectra obtained by the Mars Orbiter or the landing detector spectrometer, the various spectral features of the green alum minerals we observed in the laboratory can help identify the possible presence of green alum minerals on Mars. The spectral characteristics of the different leaf green alum minerals we observed can even be different. Further help identify the detailed species of green alum minerals in Mars. In the study of the iron sulfate phase diagram, we have established a relatively complete set of methods to study the sulfate phase diagram of hydrated iron. The thermodynamic parameters of the ferric sulfate and the boundary of their phase diagrams can help us to better understand the ferric sulphuric acid in the fire. We will compare the data of the distribution of Ti in the two typical lunar soils with the UV and visible spectra of these lunar soils, so as to better understand the relationship between the spectral intensity of the lunar soil and the Ti content in the lunar soil, the Ti minerals and the ilmenite shape.
【学位授予单位】：山东大学
【学位级别】：博士
【学位授予年份】：2011
【分类号】：P185

【共引文献】