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1.
变质沉积岩普遍含有碳质物,其源自沉积母岩中有机质。在变质过程中这些有机质逐渐转变为碳质物或石墨,且碳质物结晶程度可以作为变质等级的可靠指示标志。拉曼光谱是表征碳质物结晶度的有效工具,Beyssac et al.(2002a)基于碳质物拉曼光谱参数(R1=D1/G,D1和G为碳质物拉曼光谱峰强;R2=D1/(G+D1+D2),G、D1和D2为碳质物拉曼光谱峰面积)与寄主岩变质温度之间的线性关系构建了碳质物拉曼光谱温度计:T(℃)=-445(R2)+641,其简单且实用,并被应用到阿尔卑斯和喜马拉雅造山带热结构与折返机制研究中;随后,Rahl et al.(2005)对该变质温度计进行修订,修订后温度估算表达式为:T(℃)=737.3+320.9R1-1067R2-80.638R12,并将变质温度估算范围扩展为100~700℃。本文对碳质物拉曼光谱变质温度计的基本原理、方法、应用条件及其在造山带热结构重建与演化方面的研究进展进行了综述,并对碳质物拉曼光谱温度计与传统温度计估算的变质温度进行了系统的对比分析,结果表明碳质物拉曼光谱温度计代表峰期变质温度,不会受后期退变质影响,当传统温度计结果代表峰期变质温度时,二者计算结果一致。碳质物拉曼光谱温度计已被用于造山带热结构重建、折返过程的热演化,以及高应变带、流体相关热异常等研究。尽管变质过程的压力、变质持续时间、碳质物前体类型等因素对于碳质物拉曼光谱温度计的影响尚待研究,但与传统矿物组合温压计相结合,该方法可以有效评价峰期变质条件和造山多期热演化。  相似文献   

2.
马鞍山绿松石中水的振动光谱表征及其意义   总被引:8,自引:0,他引:8  
在室温和变温条件下对安徽马鞍山绿松石中水的结构特征进行红外吸收光谱和激光拉曼光谱分析研究,结果表明:绿松石中部分水分子与Cu2 结合成[Cu(H2O)4]2 水合离子,并在很大程度上制约了绿松石的颜色;马鞍山地区绿松石中结晶水的脱失温度约为303℃~310℃,结构水的脱失温度约为346℃~375℃。绿松石中H2O,OH-的振动是导致其水的激光拉曼光谱形成的主要原因,ν(OH)振动导致的强拉曼特征谱峰在3470 cm-1,3502 cm-1~3505 cm-1之间的弱谱峰则隶属3470 cm-1的次级谱峰,ν(H2O)的拉曼谱峰主峰位于3442 cm-1~3449 cm-1处。由ν(MFe,Cu-H2O)伸缩振动致平缓的拉曼谱峰主要分布在3074 cm-1~3303 cm-1附近。  相似文献   

3.
报道关于地球内部极端条件下的流体实验研究的最新进展。使用金刚石压砧结合各种谱学方法及同步辐射光源技术,在高温超高压条件下原位直接测量物质的结构和性质,已经获得分子-原子尺度信息新的实验数据。本项工作使用金刚石压砧对高压(10GPa)和高温高压(800℃,3GPa)条件下的NaCl-H2O进行红外谱原位直测,研究了高压和高温高压下水分子结构,发现水分子的O—H振动特征峰频率随温度向高波数变化,而且,在临界态区域时水分子间的氢键网格被破坏。实验说明:地球内部流体性质由深到浅不断变化,如水的密度、介电常数等物理参数随温度压力而改变,在临界态出现突变。这些变化可以用高压高温的物质的各种谱学特征来表征。水的性质与它的分子结构、分子振动有关。在跨越临界区时水的性质异常涨落是由水分子结构异常变化、分子振动形式变化和氢键网格破坏所导致的。从分子尺度认识地球内部流体在极端条件下的性质和高压原位实验观测有助于我们进一步了解地球深部物质的性质及其相互作用,有助于认识深部过程。  相似文献   

4.
对准噶尔盆地西大龙口剖面芦草沟组低成熟页岩干酪根进行高温高压黄金管热解实验,开展不同温度点页岩干酪根固体残渣的拉曼光谱研究。有机质的拉曼光谱具有2个特征峰,即D峰和G峰。随着热模拟温度的增加,特征峰的峰型都向窄而尖的形态发展,G峰拉曼位移基本不变,D峰拉曼位移逐渐减小,D峰和G峰的半高宽均逐渐变窄。随着成熟度的增加,固体有机质的分子结构逐渐向稳定的石墨化结构演变。拉曼参数和热模拟温度之间具有很好的相关性,G峰、D峰的峰间距d_((G-D))与热演化程度之间表现出很强的正相关关系,G峰半高宽与热演化程度之间表现出很好的负相关关系。在评价有机质成熟度时,分别用动力学参数Easy R_o和等效镜质体反射率_(Rmc)R_o对其进行热演化程度的标定,当成熟度为0.7%~2.0%时,两者对热演化产物的成熟度标定呈现出一致性。在本次实验中G峰半高宽和有机质成熟度之间有很好的负相关性。  相似文献   

5.
哀牢山金矿带位于三江特提斯造山带的东南部,发育有一系列大型-超大型造山型金矿床,并广泛发育碳质物,但碳质物在金矿成矿过程中的作用还尚不明确。为了确定碳质物在金矿化过程中所扮演的角色,本研究以哀牢山金矿带镇沅超大型造山型金矿发现的不同种类的碳质物和共生黄铁矿为研究对象,对其进行了岩相学、拉曼光谱、傅里叶红外光谱、碳同位素和激光剥蚀电感耦合等离子体质谱(LA-ICP-MS)分析,研究结果表明镇沅金矿中有3类碳质物:CM1、CM2和CM3。CM1呈深灰色不规则形态,拉曼光谱分析显示CM1具有低强度、宽的D1带和高强度、窄的G峰,D2峰较明显,计算显示其形成温度为172~200℃,低于成矿温度(250~330℃)。此外,傅里叶红外分析结果表明CM1石墨化程度低,含较少的CH键和C=O键,表明其未经历热液蚀变。碳同位素分析显示CM1样品的δ13C值为-26.46‰~-26.89‰。与CM1空间上共生的黄铁矿(Py1)呈草莓状分布于碳质板岩中,LA-ICP-MS结果表明Py1的Co、Ni、Zn、Mo、Te元素含量高;CM2呈灰色细长沥青状,拉曼光谱分析显示CM2的D1峰和G峰较CM1更为尖锐,面积近似,且D2峰的光谱分峰程度很低,计算显示其形成温度为358~463℃,高于成矿温度。傅里叶红外分析结果显示,CM2石墨化程度高,在2925 cm-1和1705 cm-1处有明显的谱峰,含有较多的CH2+CH3、C=O和C=C键。CM3呈灰色细小颗粒状,拉曼光谱分析显示CM3的光谱特征与CM1的相似,但CM3的D2峰具有独立的峰段,计算显示其形成温度为258~322℃,与成矿温度一致。碳同位素分析显示CM3的δ13C值为-9.09‰~-14.12‰。与CM3空间上共生的黄铁矿(Py2)呈自形分布于含金石英脉中,LA-ICP-MS结果表明Py2的As、Au元素含量高。综合以上结果,笔者认为CM1来源于有机质,形成于碳质板岩的早期成岩阶段,属于变质成因,与其共生的Py1形成于成岩期,属于沉积成因的黄铁矿。CM2的形成温度高于成矿温度,也为变质成因。CM3源于成矿流体,形成于围岩中的含铁矿物和成矿流体发生反应,属于热液成因,而Py2与CM3从流体中同时沉淀。其中CM1和CM3在金矿化过程中起到重要的作用。CM1作为还原剂能够有效和成矿流体中金的硫氢络合物发生水岩反应促使金的沉淀,而CM3在硫化过程中和Py2共同沉淀导致成矿流体中H2S的大量消耗,进一步破坏了金的硫氢络合物稳定性,导致金沉淀和再富集。  相似文献   

6.
张雪彤  张荣华  胡书敏 《地质学报》2016,90(8):1846-1859
地球内部极端条件下流体原位观测实验研究有了巨大进展。使用金刚石压砧结合各种谱学方法及同步辐射光源技术,在高温超高压条件下原位直接测量水和水合物结构性质,已经获得关于地球内部流体的分子-原子尺度信息的新实验数据。本次研究通过金刚石压砧对高压(10GPa)和高温高压(800℃/3GPa)NaCl-H_2O和NaCl-D_2O-H_2O的红外谱原位直测,研究了高压和高温高压下水分子结构。发现高压高温水分子OH振动频率随温度升高向高波数变化,而且,在临界态区域时水分子间的氢键网络破坏。水分子OH振动频率随盐度升高向高波数变化。水分子的其它方式运动的频率也随温度改变。实验说明了水分子在极端条件下的结构和运动方式。地球内部由深到浅,不同深度上的流体性质不断变化,如水的密度、介电常数等物理参数随温度压力改变,水的性质在临界态会出现突变。这些变化可以用高压高温的水的各种谱学特征来表征。水的性质取决于水的分子结构(键态)、分子振动方式。在跨越临界区时的水性质异常涨落与水分子结构变化、分子振动形式变化和氢键网络破坏有关。高温超高压流体原位红外谱观测实验是从分子尺度认识地球内部流体性质。水分子尺度的信息有利于我们深入理解地球深部流体性质、活动及物质相互作用,有利于理解岩石圈和地球深内部过程。  相似文献   

7.
笔者研究了内蒙古索伦地区中二叠统哲斯组泥质岩石中有机质的激光拉曼光谱特征,并探讨了拉曼光谱参数对有机质热演化程度的表征。研究区样品D1谱带吸收峰平均值位于1 350.55 cm~(-1)附近,G谱带吸收峰平均值位于1 602.55 cm~(-1)附近,G谱带与D1谱带的位置差变化于252.00±;G谱带与D1谱带的面积比集中在0.52附近,表明有机质经历的热演化温度约为250℃。应用拉曼光谱地质温度计估算了有机质的热演化温度,其平均温度为265℃;采用镜质体反射率地质温度计估算的有机质热演化平均温度为273℃,两者吻合。综合分析部分估算温度偏高的原因,结合无机矿物的成因标志,揭示研究区中二叠统哲斯组地层经历的极低级变质温度可能250℃。  相似文献   

8.
高温高压下石膏脱水相变的原位拉曼光谱研究   总被引:1,自引:0,他引:1  
周兴志  郑海飞孙樯 《岩石学报》2006,22(12):3047-3051
本文运用激光拉曼光谱仪,利用水热金刚石压腔装置对高温高压条件下石膏-水体系中的石膏脱水相变进行拉曼光谱研究。在压力0.1MPa~837.9MPa 和温度16~200℃条件下通过系列实验对相变的过程进行了原位光谱分析。与人们已知的无水条件下石膏分两步脱水的过程不同,高压下石膏在饱和水环境下倾向于一次性的脱去所有结晶水而形成无水石膏,实验中没有观察到半水石膏的出现。通过实验数据得到石膏和无水石膏的转折温度和平衡压力间的关系式为 P_(MPa)=19.56·T_(℃)-2926.5。  相似文献   

9.
使用Renishaw System-1000型激光拉曼光谱仪, 研究了大兴安岭北部上古生界泥质岩石碳质物的拉曼光谱特征及其对形成温度的表征, 探讨了拉曼光谱参数与镜质体反射率(Ro)的关系。研究表明:研究区上古生界泥质岩石碳质物不具有石墨的拉曼光谱谱带吸收峰, 揭示了地层的变质程度未达到低绿片岩相。利用此次经过完善建立的拉曼光谱地质温度计, 对大兴安岭北部上古生界泥质岩石变质温度的估算结果主要为270~320℃, 表明研究区上古生界遭受了极低级变质作用, 变质程度属近变质带。依据碳质物拉曼光谱参数与镜质体反射率的相互关系, 估算研究区有机质成熟度的Ro值主要分布为3.03%~4.23%, 与实测Ro值吻合, 表明有机质演化处于过成熟阶段, 泥质岩石具有生烃的能力, 部分层位可能具有形成油气资源的潜力。  相似文献   

10.
<正> 实验表明,有机碳质物的喇曼光谱随其成熟度的增加而具有系统性的变化:(1)16001350cm~(-1)谱峰和1350cm~(-1)谱峰的强度(高度、半高宽、峰面积)均随成熟度的增加而减弱;(2)两谱峰的相对喇曼频率位置差(分离度)随成熟度的增加而减少,即两特征谱峰的位置相对靠拢;  相似文献   

11.
东濮凹陷北部沙三中亚段广泛发育盐岩和烃源岩,这两个看似不能共存的物质却在这里互层共生。该时期研究区沉积特征为多盐韵律与多层烃源岩互层共生、连续沉积,单个盐韵律厚度从几米到十几米,烃源岩有机质丰度高、类型好。平面上,两者在湖盆沉积沉降中心共生;垂向上,高有机质丰度、好干酪根类型与高盐度地层具有较好的对应关系。因而成为恢复古气候和古环境的重要研究对象。通过岩石学、古生物学以及Sr/Ba、B/Ga、(V+Ni+Mn)、Fe/Mn、Sr/Cu、Mg/Ca、V/(V+Ni)、稀土元素含量和氯同位素等方法对凹陷北部沙三中亚段的沉积环境进行研究。结果表明,凹陷北部沙三中亚段为深水沉积的还原环境,古盐度较高,达到半咸水-咸水沉积;微量元素和孢粉化石特征表明研究区沙三中亚段为温暖潮湿的环境。  相似文献   

12.
In order to characterise the influence of the heavyrains on the observed landslides during the 1996–1997hydrological cycle, rainfall records for the last 100years are analysed from 104 stations in easternAndalusia. Regarding the amounts of rain recordedbetween October 1996 and March 1997 in the 104stations studied, 31 presented new all-time records;15 presented values that were 80–100% of thepre-1995 record; 49 stations, 80–50%; and 9stations, < 50%. A map has been devised of thesusceptibility of the materials through which thesouth-eastern Andalusian road network crosses,together with an inventory of the damage caused byinstability phenomena on banks and cuttings of theroad network during the winter of 1996–1997. Therelationships between the rainfall during the studyperiod, the damage caused to the road network and thesusceptibility of the materials affected are analysed.The results indicate that there is a clearcorrespondence between the rainfall recorded and thesusceptibility of the materials with the inventorieddamage. It is concluded that the widespread seriousdamage caused in early 1997 to the roads andsurrounding areas in the Alpujarra region and thecoast of the Province of Granada was mainly caused bythe extraordinarily heavy rains. However, considerablyless damage was observed where the susceptibility ofthe terrain is low, thus highlighting the extremeusefulness of terrain-susceptibility maps for riskprevention and territorial planning.  相似文献   

13.
郯庐断裂南段研究进展与断裂性质讨论   总被引:13,自引:3,他引:13  
据1:5万区域地质调查和专题研究资料,就郯庐断裂带是否南延与消失的原因,其与大别—苏鲁造山带交截形成的假位错效应,以及与中新生代沉积盆地形成演化的关系等作了新的阐述。在此基础上,讨论了郯庐断裂带是否为巨大的左行平移断层或转换断层。认为郯庐断裂带可能是在“古郯庐带”的基础上于早侏罗世重新活动、白垩纪强烈活动的地堑型枢纽断裂带。  相似文献   

14.
International unity is becoming ever stronger in this country owing to an increasing similarity in the development of the cultural environment. This comprises the provision of all the country's republics with a sufficient number of schools, theatres, and other institutions and cultural information media in accordance with the needs of the population. An important part is played by the rise in ‘the general educational level, as well as the level of professional qualifications and skills. Among all the Soviet nations and nationalities, this rise being more rapid among formerly backward peoples. Prominent among the factors of internationalization is the progressive development of the nationalities’ cultural resources, while professional culture is being increasingly brought within the reach of the masses.The implementation of the nationalities policy promotes the all-round development of all Soviet nations and nationalities, their drawing together, the upsurge of the individual capabilities of every Soviet citizen.  相似文献   

15.
某高速公路下伏煤矿采空区稳定性分析   总被引:10,自引:0,他引:10  
在论述某高速公路下伏砦脖煤矿采空区地质、采矿和工程地质特征的基础上, 进行了稳定性数值模拟分析, 定性与定量地分析与评价了该煤矿采空区的地表变形特征及稳定性。研究结果表明: 该煤矿采空区的变形尚未完成, 对拟建的高速公路将产生很大的危害, 必须采取相应的工程治理措施。   相似文献   

16.
塘口水电站大坝基础座落在断层和裂隙较发育的龟裂纹灰岩上,岩体完整性差、透水性强,多年运行后,大坝灌浆廊道和排水廊道出现多处集中性漏水,为确保大坝安全和电站正常发电,根据渗漏性质和成因,采用对灌浆廊道补充帷幕灌浆,对排水廊道进行固结+帷幕+回填灌浆。通过灌浆处理后,效果良好,表明灌浆工程有效的将导致坝基渗漏的上下游的裂隙通道封闭,并顺利的经受了随后的汛期洪水考验,大坝安全得到保障。  相似文献   

17.
The Global Stratotype Section and Point (GSSP) for the base of the Silurian System was defined in 1985. Since that time, a number of researchers have suggested that this section has serious deficiencies for use as a GSSP. As a result, in 2000, the Subcommission on Silurian Stratigraphy (SSS) proposed undertaking a formal restu@ of this GSSP, which was subsequently approved by the International Commission of Stratigraphy (ICS). The result of this restudy was the formal proposal that the current GSSP, at 1.6 m above the base of the Birkhill Shale, at Dob's Linn, Scotland, should be maintained as the same locality and stratigraphic level, but the bios- tratigraphical definition of the boundary should be revised. The previously defined, basal Silurian grapto- lite zone, the Parakidograptus acuminatus Zone, should be subdivided into a lower Akidograptus ascensus Zone and a higher E acuminatus Zone. The base of the A. ascensus Zone, marked by the first appearance of A. ascensus, should be regarded as the biostratigraphic mark for the base of the Silurian. This proposal has now been formally approved by the SSS and ICS, and ratified by International Union of Geological Sciences. This is the first GSSP to undergo formal restudy and redefini- tion, and the proposal also included a recommended procedure for restudy of GSSPs.  相似文献   

18.
In reservoir characterization, the covariance is often used to describe the spatial correlation and variation in rock properties or the uncertainty in rock properties. The inverse of the covariance, on the other hand, is seldom discussed in geostatistics. In this paper, I show that the inverse is required for simulation and estimation of Gaussian random fields, and that it can be identified with the differential operator in regularized inverse theory. Unfortunately, because the covariance matrix for parameters in reservoir models can be extremely large, calculation of the inverse can be a problem. In this paper, I discuss four methods of calculating the inverse of the covariance, two of which are analytical, and two of which are purely numerical. By taking advantage of the assumed stationarity of the covariance, none of the methods require inversion of the full covariance matrix.  相似文献   

19.
It is known from observations that the center of mass of the Moon does not coincide with the geometric center of its figure, and the line connecting these two centers is not aligned with the direction toward the center of the Earth, instead deviating toward the Southeast. This stationary deviation of the axis of the inertia ellipsoid of the Moon to the South of the direction toward the Earth is analyzed. A system of five linear differential equations describing the physical libration of the Moon in latitude is considered, and these equations are derived using a new vector method taking into account perturbations from the Earth and partly from the Sun. The characteristic equation of this system is obtained, and all five oscillation frequencies are found. Special attention is paid to the fifth (zero) frequency, for which the solution of the latitude libration equations are stationary and represents a previously unknown additional motion of the rotational axis of theMoon in a cone with a small opening angle. In contrast to the astronomical precession of the Earth, the rotation of the angular-velocity vector is in the positive direction (counter-clockwise), with the period T 3 = 27.32 days. On this basis, this phenomenon has been named “quasi-precession.” This quasi-precession leads to a stationary inclination of the major axis of the inertia ellipsoid of theMoon to the South (for an observer on Earth), making it possible to explain one component of the observed deviation of the center of mass of the Moon from the direction toward the Earth. The opening angle of the quasiprecession cone is approximately 0.834″.  相似文献   

20.
正Artemia cysts are an extremely important component of aquaculture diets.It is well established that the cultivation of fish and shellfish derive substantial health and growth advantages when Artemia are included in the diets of the  相似文献   

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