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1.
岩石电子背散射衍射（EBSD）组构分析及应用 总被引：18，自引：1，他引：17
电子背散射衍射（EBSD）技术是现代构造地质学与显微构造分析领域一项崭新的技术,它与现代高分辨率扫描电子显微镜和能谱分析设备结合,可以对块状样品中微米或纳米级尺度的颗粒进行晶体结构分析, 从而使微观结构、微区成分与结晶学数据结合起来,能够更精细地对比研究矿物和岩石显微构造,为岩石显微构造分析开辟了一个全新的领域。分析了EBSD技术的基本原理、系统构成、样品制备和工作程序。介绍了石英组构测量,极细粒物质（微角砾岩）的组构特点,二轴晶矿物（角闪石）的组构、变形机制和金属硫化物组构分析的应用实例,对于应用EBSD系统开展研究存在的一些问题进行了讨论。 相似文献
2.
岩石显微构造分析现代技术——EBSD技术及应用 总被引：10，自引：0，他引：10
EBSD技术的发展，为岩石显微构造分析开辟了一个全新的领域。它与现代扫描电子显微镜和能谱分析等设备配合，可以同时对块状样品进行晶体结构与成分分析,从而使显微构造、微区成分与结晶学数据分析有机结合起来。
EBSD技术可以精确、快速定量标定包括各种晶系晶体颗粒的晶格方位和描述晶体颗粒的边界、形态等特征，对于具有低角度边界的晶体颗粒提供精确数据,为阐述岩石变形机制提供重要约束，并为高级晶族和不透明矿物结晶学组构与变形机制研究提供了有效的手段。EBSD尤其使获取微米级甚至纳米级尺度上颗粒（亚颗粒）或相之间的定向差别（达到20 nm的空间分辨率和0.3度角度分辨率）成为可能。EBSD技术在矿物相鉴定、亚微域内的应变分析、矿物出溶作用等方面的应用，进一步证明了这一新技术在显微构造分析及相关领域的应用前景。其广泛应用必将带来岩石显微构造研究的新突破，也将成为未来岩石变形机制与岩石圈流变学研究取得飞速发展不可或缺的技术手段。 相似文献
3.
电子背散射衍射（EBSD）技术在大陆动力学研究中的应用 总被引：14，自引：10，他引：4
电子背散射衍射（Electron backscatter diffraction,简称EBSD）技术可以快捷准确地进行物相鉴定,确定矿物晶体的晶格优选定向和多相岩石中各矿物的空间分布,使其成为定量研究岩石显微构造的理想工具。将岩石组构测量、野外地质观察与矿物的变形实验研究相结合,可以判别物质运动的剪切指向和变形的温压条件,从而进行运动学和动力学机制的分析。本文首先介绍了EBSD技术的原理和主要矿物组构的实验研究进展,然后以国土资源部大陆动力学重点实验室5年来的成果为例,总结了EBSD技术在研究大陆深俯冲和折返的动力学机制和大陆造山带动力学研究中的应用。结果表明：橄榄石和绿辉石的组构揭示了板块深俯冲阶段的组构运动学特征,而石英、斜长石和夕线石的组构可以用来研究地壳内大型韧性剪切带的变形历史,如与苏鲁超高压变质岩折返相关的韧性剪切带、龙门山逆冲剪切带、西昆仑康西瓦走滑剪切带和喜马拉雅造山带的康马拆离剪切带。因此,EBSD技术的应用有助于实现显微构造与宏观构造相结合,建立变质-变形-运动学相统一的地球动力学模型。 相似文献
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5.
何永年 《矿物岩石地球化学通报》1985,(1)
变形矿物岩石的显微构造研究与组构分析,有助于阐明和恢复岩石变形过程中的环境条件和变形历史。因此,凡是与岩石变形有关的地质学问题,变形显微构造研究和组构分析都可以直接或间接地发挥作用。近年来,地学工作者越来越清楚地认识到,大型、中型、小型与微型构造之间存在密切的联系和成因上的相似性,也更加注意到结晶物质在变形过程中不 相似文献
6.
近一二十年,岩石磁学有了飞速发展,并在地质学领域内占有越来越重要的位置。国内外研究的焦点是磁组构与应变相关性以及磁组构在岩浆岩、沉积岩构造分析中的应用。本文着重研究了未变形火山熔岩的磁组构特征,为火山岩的磁组构与有限应变相关性等项研究提供基本对比参照体系,也为室内有关的模拟实验提供依据。 相似文献
7.
橄榄岩作为上地幔的主要成分,影响着上地幔的流变学行为,其显微构造记录了岩石形成发展过程中所经受的构造事件.通过对祁连山玉石沟橄榄岩样品的镜下显微构造观察、岩石组构测定及TEM位错分析,探讨了与变形相关的温度、围压、含水性和应变速率等因素,总结该岩石的变形机制和变形历史,并推断其形成发展时大地构造环境.研究表明,玉石沟橄榄岩产自上地幔,其变形改造经历了上地幔演化和脆-韧性变形2个阶段.上地幔演化阶段橄榄石发育明显的A型原生组构,电子背散射衍射技术（EBSD）测定的橄榄石显微组构表明,该地区橄榄岩形成于高温（＞ 1200℃）、低应力（＜350 MPa）、低应变速率、低含水量的地幔浅部环境条件下;脆-韧性变形阶段叠加改造了原生A型组构,而发育明显的D型次生组构.橄榄石变形主控因素为动态恢复作用,普遍发育亚晶粒、消光带和扭折显微构造等相关组构,并与透射电镜下所观察到的位错排对应,同时还发育以微破裂为主的一套脆性变形组构,表现出两组共轭剪破裂和另一组张性破裂等现象,揭示出与韧性动态恢复现象一致的应力场方向指示. 相似文献
8.
迁安铁矿是我国大型沉积变质型铁矿之一,该矿区含矿变质岩系为前寒武纪老变质岩石,时代老,变质程度深,现存岩石的内部矿物发生过多次变形、变质和重结晶等变化,宏观上表现为该区岩石矿物组构的复杂性。为了更深入、清晰地了解该区变形岩石的组构,采用电子背散射衍射(EBSD)技术对该区岩石样品做了分析,通过EBSD系统的配套软件(HKL公司开发的Channel 5),对采集数据进行处理绘制成相应磁铁矿和石英的极图,经分析后重点总结出变形岩石内部石英的组构特点,由此进一步反映出本区构造变形时主要为中温-中高温的变形温度环境,少量组构图反映叠加了中低温变形。 相似文献
9.
电子背散射衍射(EBSD)技术在地壳构造变形研究中的应用 总被引：1，自引：0，他引：1
电子背散射衍射(EBSD)技术是岩组学研究的一项革命性新技术。该技术可以对传统的岩石薄片进行分析,实用性高,观测精度达到亚微米级别。配合扫描电子显微镜、阴极发光、波谱、能谱分析设备,EBSD技术可以对透明和非透明的任何对称性晶体进行取向测量,快速获取晶体显微结构、微区成分与晶体学参数,可以对晶体开展形貌观察、晶体优选方向(CPO)、取向差分析、物相鉴定、应变测量、晶界分析、变形机制、位错滑移系、晶内变形、温压条件研究。结合聚焦离子束(FIB)技术,可以获取矿物的三维结构图像。对地壳的主要矿物进行组构分析,结合野外矿物变形特征与试验岩石学研究成果,可以开展地壳构造运动学、动力学的研究。本文介绍岩组学的研究历史,以及EBSD技术在地壳常见矿物石英、钾长石、斜长石、角闪石以及假熔岩构造变形研究中的最新进展与典型实例,并对EBSD研究结果中一些潜在的不确定性因素进行了讨论。 相似文献
10.
岩石磁性组构及其在构造地质中的应用 总被引：1，自引：0，他引：1
岩石磁性组构是指岩石内部决定磁化率各向异性强度和方位的矿物组构。它们能反映岩石形成过程或经历构造变动过程的一系列地质信息。本文在简单评述岩石磁性组构的物理学含义与表达方式的基础上,着重介绍了在构造地质分析中,磁性组构作为一种有效手段之一的应用现状。这里主要讨论了以下几个方面;1)磁性组构与岩石应变量之间的线性关系;2)磁性组构在剪切带研究中作为岩石相对运动的指向标志;3)磁性组构有可能揭示某些构造形迹的成因机理。最后,指出了磁性组构在构造地质分析中的应用所存在的一些问题和可能的解决方法。 相似文献
11.
We ask the question whether petrofabric data from anisotropy of magnetic susceptibility (AMS) analysis of deformed quartzites gives information about shape preferred orientation (SPO) or crystallographic preferred orientation (CPO) of quartz. Since quartz is diamagnetic and has a negative magnetic susceptibility, 11 samples of nearly pure quartzites with a negative magnetic susceptibility were chosen for this study. After performing AMS analysis, electron backscatter diffraction (EBSD) analysis was done in thin sections prepared parallel to the K1K3 plane of the AMS ellipsoid. Results show that in all the samples quartz SPO is sub-parallel to the orientation of the magnetic foliation. However, in most samples no clear correspondance is observed between quartz CPO and K1 (magnetic lineation) direction. This is contrary to the parallelism observed between K1 direction and orientation of quartz c-axis in the case of undeformed single quartz crystal. Pole figures of quartz indicate that quartz c-axis tends to be parallel to K1 direction only in the case where intracrystalline deformation of quartz is accommodated by prism <c> slip. It is therefore established that AMS investigation of quartz from deformed rocks gives information of SPO. Thus, it is concluded that petrofabric information of quartzite obtained from AMS is a manifestation of its shape anisotropy and not crystallographic preferred orientation. 相似文献
12.
Petrofabric Analyses of Rhum and Skaergaard Layered Rocks 总被引：1，自引：0，他引：1
Petrofabric analyses of layered rocks from Rhum have revealeda preferred orientation for felspar in the allivalites and forolivine in the peridotites; a regional petrofabric map of felsparorientation contains a radial pattern which suggests the presenceof convection currents during crystal settling. An orientedspecimen of Skaergaard ferrogabbro from the margin of a troughband has allowed comparison to be made between a known magmacurrent direction and the preferred orientation of felspar,olivine, clinopyroxene, and apatite crystals in the rock. 相似文献
13.
中国显微构造地质学的回顾 总被引：3，自引：0，他引：3
我国的显微构造与组构研究始于20世纪30年代。已故何作霖教授把“岩组学”由德语文献介绍到中国，王嘉荫教授实测了国内岩石的岩组图，研究了矿物形成与变化的构造作用因素，他们把这一领域的研究与构造地质分析结合起来，结合构造地质分析引入了显微镜方法。不过在以后的30多年里，显微构造与组织分析只局限于少数学术单位和少数学者。从20世纪70年代中期开始，随着地 质工作的发展和国际交往的带动，显微构造与组构在我国得到较快速的发展。许多高校地质系开设了相关课程，在矿业开发、工程地质、环境与灾害地质等方面也得到有成效的应用。 相似文献
14.
D. F. Wiggers de Vries M. R. Drury D. A. M. de Winter G. P. Bulanova D. G. Pearson G. R. Davies 《Contributions to Mineralogy and Petrology》2011,161(4):565-579
As a step towards resolving the genesis of inclusions in diamonds, a new technique is presented. This technique combines cathodoluminescence
(CL) and electron backscatter diffraction (EBSD) using a focused ion beam–scanning electron microscope (FIB–SEM) instrument
with the aim of determining, in detail, the three-dimensional diamond zonation adjacent to a diamond inclusion. EBSD reveals
that mineral inclusions in a single diamond have similar crystallographic orientations to the host, within ±0.4°. The chromite
inclusions record a systematic change in Mg# and Cr# from core to the rim of the diamond that corresponds with a ~80°C decrease
of their formation temperature as established by zinc thermometry. A chromite inclusion, positioned adjacent to a boundary
between two major diamond growth zones, is multi-faceted with preferred octahedral and cubic faces. The chromite is surrounded
by a volume of non-luminescent diamond (CL halo) that partially obscures any diamond growth structures. The CL halo has apparent
crystallographic morphology with symmetrically oriented pointed features. The CL halo is enriched in ~200 ppm Cr and ~80 ppm
Fe and is interpreted to have a secondary origin as it overprints a major primary diamond growth structure. The diamond zonation
adjacent to the chromite is complex and records both syngenetic and protogenetic features based on current inclusion entrapment
models. In this specific case, a syngenetic origin is favoured with the complex form of the inclusion and growth layers indicating
changes of growth rates at the diamond–chromite interface. Combined EBSD and 3D-CL imaging appears an extremely useful tool
in resolving the ongoing discussion about the timing of inclusion growth and the significance of diamond inclusion studies. 相似文献
15.
Maria Dolores Ruiz Cruz 《Mineralogy and Petrology》2011,101(3-4):245-261
Atoll-shaped and normal garnets from schists of the Betic Cordillera (Spain) were studied by electron microprobe, scanning electron microscopy and microstructural electron backscattered scanning diffraction (EBSD). Medium-grade schists contain a textural variety of atoll garnets, characterized by the presence of muscovite, annite, and quartz as main ??core?? phases. Zoning patterns, EBSD analyses and themobarometric data indicate that the micaceous intergrowths formed in most cases through breakdown of a first garnet generation, with orientation of micas being controlled by garnet (c*mica//[111]*Grt and c*mica//[110]*Grt as main crystallographic relationships). Rings formed from multiple nucleation and coalescence, with orientation being controlled, in some cases, by the relics of the initial garnet and more generally by mica orientation. P-T estimates indicate that the first stage of garnet growth occurred at relatively high P (9?C12?kbar/500?C550°C) whereas the second metamorphic stage occurred at lower P and slightly higher T conditions (5?C7?kbar/500?C600°C). 相似文献
16.
Within a mica schist from the coesite-bearing Brossasco-Isasca Unit (Western Alps), microstructural analysis shows that Alpine garnet grains are aligned with the crenulated foliation. Garnet crystallographic orientation was analysed with electron backscatter diffraction (EBSD): the obtained crystallographic dispersion patterns and distribution patterns of misorientation axes suggest a strong parallelism of {110} garnet planes with a 56°W-dipping foliation. The data are interpreted as evidence for an epitaxial growth of garnet upon (001) biotite planes, sometime during and/or after dispersion of the biotite/garnet crystals from their initially foliation-parallel orientation by rotation about the Alpine crenulation axis. This interpretation is based on the comparison of the measured EBSD data with: (i) theoretical dispersion trajectories of garnet crystallographic data, (ii) numerically modelled pole figures, and (iii) numerically modelled misorientation axis distribution patterns. Our data suggest that epitaxial growth of garnet upon biotite is allowed by distortion of the pseudohexagonal basal oxygen ring structure on (001) biotite surfaces, and that distortion is driven by introduction of missing ions. Our data further suggest that the spatial distribution of precursor phases influences the distribution patterns of garnet within mica schists. 相似文献
17.
We present the influence of mineralogy and microstructure on the seismic velocity anisotropy of evaporites. Bulk elastic properties and seismic velocities are calculated for a suite of 20 natural evaporite samples, which consist mainly of halite, anhydrite, and gypsum. They exhibit strong fabrics as a result of tectonic and diagenetic processes. Sample mineralogy and crystallographic preferred orientation (CPO) were obtained with the electron backscatter diffraction (EBSD) technique and the data used for seismic velocity calculations. Bulk seismic properties for polymineralic evaporites were evaluated with a rock recipe approach. Ultrasonic velocity measurements were also taken on cube shaped samples to assess the contribution of grain-scale shape preferred orientation (SPO) to the total seismic anisotropy. The sample results suggest that CPO is responsible for a significant fraction of the bulk seismic properties, in agreement with observations from previous studies. Results from the rock recipe indicate that increasing modal proportion of anhydrite grains can lead to a greater seismic anisotropy of a halite-dominated rock. Conversely, it can lead to a smaller seismic anisotropy degree of a gypsum-dominated rock until an estimated threshold proportion after which anisotropy increases again. The difference between the predicted anisotropy due to CPO and the anisotropy measured with ultrasonic velocities is attributed to the SPO and grain boundary effects in these evaporites. 相似文献