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1.
黄山东镁铁超镁铁杂岩中的辉石化学成分研究 总被引：7，自引：0，他引：7
通过对黄山东镁铁超镁铁杂岩的辉石化学成分研究，证明辉石的化学成分受寄主岩石类型的制约，从超镁铁岩相到角闪辉长岩相斜方辉石的化学成分由富ＭｇＯ、ＳｉＯ＿２、Ａｌ＿２Ｏ＿３、Ｃｒ＿２Ｏ＿３到富ＦｅＯ、ＴｉＯ＿２、ＣａＯ、ＭｎＯ；单斜辉石化学成分由富Ａｌ＿２Ｏ＿３、Ｃｒ＿２Ｏ＿３、Ｎａ＿２Ｏ、ＭｇＯ到富ＦｅＯ、ＭｎＯ、ＣｏＯ。在同一寄主岩石中，单斜辉石比斜方辉石富ＴｉＯ＿２、Ａｌ＿２Ｏ＿３、Ｃｒ＿２Ｏ＿３、ＣａＯ和Ｎａ＿２Ｏ，贫ＭｇＯ、ＳｉＯ＿２、ＭｎＯ和ＦｅＯ。根据辉石化学成分特征得出黄山东杂岩形成于岛弧环境，为上地幔石榴二辉檄榄岩部分熔融形成的拉斑玄武岩岩浆结晶分异作用的产物。 相似文献
2.
本文用强功率四圆单晶衍射仪精确地修正了独居石和磷钇矿的晶体结构。独居石［Ｍｏｎａｚｉｔｅ－（Ｃｅ），ＣｅＰＯ４］属单斜晶系，ａ＝６．７８４３（１７），ｂ＝６．９８９１（１２），ｃ＝６．４５９２（１０），β＝１０３．６２６（１６）°，Ｚ＝４，空间群为Ｐ２１／ｎ。使用１１０６个［Ｆ≥３σ（Ｆ）］的独立衍射点，经多轮最小二乘法修正后，最终获得偏离因子Ｒ＝０．０６０。独居石的结构由孤立的［ＰＯ４］四面体构成，Ｃｅ位于［ＰＯ４］四面体包围之中，Ｃｅ的配位数为９，独居石的Ｃｅ—Ｏ平均键长为２．５５２，Ｐ—Ｏ平均键长为１．５２８。磷钇矿（Ｘｅｎｏｔｉｍｅ，ＹＰＯ４）属四方晶系，其晶格常数为：ａ＝６．８７９１（２４），ｃ＝６．０１４７（１９），Ｚ＝４，空间群为Ｉ４Ｉ／ａｍｄ（Ｎｏ．１４１）。使用１４２个［Ｆ≥３σ（Ｆ）］的独立衍射点，经多轮最小二乘法修正后，最终获得偏离因子Ｒ为０．０４８３。磷和氧形成四面体配位，其Ｐ—Ｏ平均键长为１．５４３；稀土钇与氧原子相连构成八次配位，其Ｙ—Ｏ平均键长为２．３３３。 相似文献
3.
Ａｌ２ＳｉＯ５多型矿物中铝的Ｋ边Ｘ射线吸收近边结构研究李迪恩彭明生（中山大学宝石矿物材料研究所，广州５１０２７５）关键词铝硅酸盐配位Ｘ射线吸收近边结构在铝硅酸盐矿物中，Ａｌ通常为四面体和／或八面体配位，但在红柱石中Ａｌ也可为五次配位，因此，在铝硅酸盐... 相似文献
4.
八庙—青山金红石矿床化学成分与成矿关系 总被引：1，自引：0，他引：1
本矿床是我国金红石矿床重要的成因及工业类型，为具有特定化学成分的岩石在特定变质条件下形成的。本文通过对大量数据的处理，查明了化学成分和成矿的关系，高Ａｌ２Ｏ３，ＭｇＯ，Ｆｅ２Ｏ３＋ＦｅＯ，Ｋ２Ｏ，Ｐ２Ｏ５，Ｈ２Ｏ＾＋，ＭｎＯ，低ＳｉＯ２，ＣａＯ，Ｎａ２Ｏ，ＣＯ２，Ｓ等，利于钛富集；高ＴｉＯ２，ＭｇＯ，Ｐ２Ｏ５，Ｓ，低ＳｉＯ２，ＣａＯ，Ｋ２Ｏ，Ａｌ２Ｏ３，Ｆｅ２Ｏ３／ＦｅＯ，利于金红石形成，高Ｓｆ， 相似文献
5.
Li Xianzhou 《吉林大学学报(地球科学版)》1994,(4)
水厂麻粒岩中辉石的穆斯堡尔效应研究表明，斜方辉石的谱图为两组四极双峰，分别由Ｍ＿１和Ｍ＿２位上的高自旋态Ｆｅ￣（２＋）产生，而单斜辉石则为三组四极双峰，其中两组较强的双峰分别由Ｍ＿１和Ｍ＿２位上的Ｆｅ￣（２＋）产生，第二组弱双峰是由四面体和八面体位置上的Ｆｅ￣（３＋）共同产生的。水厂麻粒岩中辉石的有序程度高，并且斜方辉石有序度大大高于单斜辉石，而单斜辉石Ｍ＿１、Ｍ＿２位置的畸变程度高于斜方辉石。在压力相同的条件下，Ｆｅ￣（２＋）的有序度具有明显地温度效应，高温有利于Ｆｅ￣（２＋）做有序分布。 相似文献
6.
我国产出的砷铅矿族矿物的研究 总被引：3，自引：0，他引：3
砷铅矿族矿物是一族六方晶系的类质同象系列矿物，包括砷铅矿、钒铅矿和磷氯铅矿。砷铅矿呈淡黄色、浅黄绿色和灰白色六方柱状晶体产出，Ｈｍ＝３．５，Ｄ≥６．７５ｇ／ｃｍ３，一轴晶负光性，Ｎ＞２，晶胞参数为ａ０＝１．０２５１ｎｍ，Ｃ０＝０．７４４ｎｍ，Ｚ＝２。广西德保矿区产出的砷铅矿的化学成分为（ｗｔ．％）：ＰｂＯ７４．９４，Ａｓ２Ｏ５１９．５３，Ｐ２Ｏ５２．３１，ＣｕＯ０．３６，Ｃｌ２．４１，总量为９９．５５。云南个旧矿区产出的钒铅矿呈桔红色至红褐色，六方短柱状自形晶，Ｈｍ＝３．０，Ｄｘ＝６．９５ｇ／ｃｍ３，一轴晶负光性，Ｎ＞２，晶胞参数为ａ０＝１．０３１ｎｍ，Ｃ０＝０．７４３ｎｍ，Ｚ＝２，空间群为Ｐ６３／ｍ，其化学成分为（ｗｔ．％）：ＰｂＯ７９．９８，Ｖ２Ｏ５１８．９４，Ｃｌ２．６１，总量为１０１．５３。广西阳朔产出的磷氯铅矿，呈暗绿色六方柱状晶体产出，Ｈｍ＝３．５，Ｄ＝６．９８ｇ／ｃｍ３，一轴晶正光性，Ｎ＝２±，平均化学成分为（ｗｔ．％）：ＰｂＯ８１．６４，Ｐ２Ｏ５１５．０８，Ａｓ２Ｏ５０．１０，ＣｕＯ０．２０，Ｃｌ２．６７，总量为９９．６９。 相似文献
7.
李宪洲 《长春地质学院学报》1994,24(4):406-408
水厂麻粒岩中辉石的穆斯堡尔效应研究表明，斜方辉石的谱图为两组四极双峰，分别由Ｍ１和Ｍ２位上的高自旋态Ｆｅ＾２＋产生，而单斜辉石则为三组四极双峰，其中两组较强的双峰分别由Ｍ１和Ｍ２位上的Ｆｅ＾２＋产生，第二组弱双峰是由四面体和八面体位置上的Ｆｅ＾３＋共同产生的。水厂麻粒岩中辉石的有序程度高，并且斜方辉石有序度大大高于单斜辉石，而单斜辉石Ｍ１、Ｍ２位置的畸变程度高于斜方辉石。在压力相同的条件下，Ｆｅ＾ 相似文献
8.
流动注射—催化光度法测定痕量锰 总被引：3，自引：0，他引：3
在非离子表面活性剂吐温－８０存在的Ｈ３ＰＯ４介质中，Ｍｎ＾２＋对Ｖ（Ｖ）氧化二安替比林苯乙烯甲烷（ＤＡＶＰＭ）成红色化合物的反应具有较强的催化作用，基于此采用流动注射－催化光度法测定了痕量Ｍｎ＾２＋，该方法的检测波长为５５５ｎｍ，检出限为０．０２μｇ／Ｌ Ｍｎ，线性范围为０．０２￣６μｇ／Ｌ Ｍｎ，进样频率为６０次／ｈ，对５μｇ／Ｌ Ｍｎ进行１０次测定的相对标准偏差为１．８％。经环境标准样品分析验 相似文献
9.
西秦岭寒武系金矿床中硅岩的地质地球化学特征及其沉积环境意义 总被引：31，自引：4，他引：27
西秦岭寒武系中的硅岩是拉尔玛－邛莫层控金矿床的主要赋矿岩石之一。含矿硅岩呈块状、条带状、层纹状、多孔状和同生角砾状等。硅岩单层厚度一般为３０～２００ｍ。主要成分ＳｉＯ２平均含量高达９５．３０％,其余为ＦｅＯ、Ｆｅ２Ｏ３和有机炭等。硅岩的Ａｌ／（Ａｌ＋Ｆｅ＋Ｍｎ）比值低于０．３（平均０．１５３）,投点于Ｆｅ／Ｔｉ－Ａｌ／（Ａｌ＋Ｆｅ＋Ｍｎ）图解和Ａｌ－Ｆｅ－Ｍｎ三角图解上,均落于热水沉积物区。硅岩中微量元素十分丰富,不仅含有具基性、超基性特征的元素群（如Ｃｕ、Ｃｒ、Ｐｔ、Ｐｄ、Ｏｓ等）,而且还含有具酸性特征的元素群（如Ｗ、Ｍｏ、Ｕ等）。硅岩中稀土以总量（３．２９～１００μｇ／ｇ）低和铈亏损为特征。经北美页岩标准化后的稀土比值随原子序数的增大而增大。硅岩的δ１８Ｏ值为１７．６０‰～２３．２４‰,据此得到它形成的温度为７０．９℃～１１８．１℃。硅岩的δ３０Ｓｉ值主要为＋０．４‰～＋０．８‰。上述硅岩的特点均显示其与喷流热水沉积作用有关。硅岩中Ｐ２Ｏ５含量、Ｓｒ／Ｂａ比值、δＣｅ值以及δ３０Ｓｉ值表明,它主要是在深海—半深海环境下形成的。 相似文献
10.
11.
本文根据畴结构的群论原理,对有序绿辉石的空间群归属问题(P2还是P2/n)进行了讨论。通过把无序绿辉石的空间群C2/c分别相对于P2和P2/n的陪集展开可以得知,C2/c→P2相变将产生■的反相畴及■(001/2)和(■1/2 1/2 1/2)两种倒反孪晶,而C2/c→P2/n相变则仅产生■/2的反相畴,显然后者与有序绿辉石畴结构的透射电境观察结果一致。因此可以断定,有序绿辉石的空间群为P2/n,而非P2。 相似文献
12.
G. Salviulo F. Princivalle G. Demarchi C. Fabro 《Physics and Chemistry of Minerals》1992,19(4):213-219
X-ray crystal structure refinements and microprobe analyses of clinopyroxenes from two suites of spinel-peridotite nodules are compared for an understanding of the structural response to a decrease in Ca content. The kinking of the tetrahedral chain (O3-O3-O3 angle) of the C2/c structure associated with decreased Ca content shows behavior similar to that observed for the A-tetrahedral chain of the P21/c structure. Contemporaneously the occupancy of the M2′ split site increases. In addition, as a consequence of the low Ca content, the M2 polyhedron dominates the structural rearrangement of the clinopyroxenes considered here. 相似文献
13.
TEM and HRTEM Study of Microstructures in Omphacite from UHP Eclogites at Shima, Dabie Mountains, China 总被引：1，自引：0，他引：1
WU Xiuling HAN Yujing MENG Dawei YANG Weiran LI DouxingTest Center Faculty of Earth Sciences China University of Geosciences Wuhan HubeiLaboratory of Atomic Imaging of Solids Institute of Metal Research Chinese Academy of Sciences Shenyang Liaoning 《《地质学报》英文版》2000,74(2):154-162
Transmission electron microscope (TEM) and high resolution transmission electron microscope (HRTEM) analyses have been performed on omphacite from ultra-high pressure (UHP) eclogites at the locality of Shima, Dabie Mountains, China. TEM reveals that the microstructures consist dominantly of dislocation substructures, including free dislocations, loops, tiltwalls, dislocation tangles and subboundaries. They were produced by high-temperature ductile deformation, of which the main mechanism was dislocation creep. Antiphase domain (APD) boundaries are common planar defects; an age of 470±6 Ma for UHP eclogite formation has been obtained from the equiaxial size of APDs in ordered omphacites from Shima, coincident with ages given by single-zircon U-Pb dating (471±2 Ma). HRTEM reveals C2/c and P2ln space groups in different parts of one single omphacite crystal, and no exsolution is observed in the studied samples, which is attributed to rapid cooling. It is suggested that the UHP eclogites underwent a long 相似文献
14.
Giuseppe Rossi David C. Smith Luciano Ungaretti M. Chiara Domeneghetti 《Contributions to Mineralogy and Petrology》1983,83(3-4):247-258
The Nybö eclogite pod in Norway is characterized by a great variety of clinopyroxene compositions with Jd contents ranging from less than 5% up to nearly 80%, whilst Ac+Hd contents remain almost constant (mostly within 10±5%).Unconstrained X-ray structure refinement has been carried out on 16 pyroxene crystals (8 with C2/c and 8 with P2/n space group) from the Nybö eclogite, and also on one omphacite crystal (from Lago Mucrone in the Sesia-Lanzo Zone, Western Alps) which displays the highest degree of cation ordering yet described. The final discrepancy factors range from 0.014 to 0.029. The population of the sites has been determined on the basis of bond length considerations and of the results of the site occupancy refinement. Six of these crystals were subsequently analysed by electron microprobe.The tetrahedral sites are occupied by Si with negligible amounts of Al. Al, Mg, Fe3+ and Fe2+ occur at the octahedral sites; in the ordered P2/n crystals Al and Fe3+ are concentrated at the M11 site, whilst Mg and Fe2+ are concentrated and the M1 site. The eight-coordinated sites contain Ca and Na with negligible amounts of Fe and/or Mg. Ordering of Ca and Na takes place in the P2/n samples in such a way that in the most ordered crystal the M2 site contains almost exactly 0.75 Na+0.25 Ca and the M21 site 0.25 Na+0.75 Ca.Some geometrical features of the tetrahedra as well as of the octahedra (e.g. tetrahedral quadratic elongation and TILT angle) are not a simple linear function of composition, even when no change in space group occurs. The crystals evidently do not behave like a binary system of the two components, Di and Jd, but behave rather as if the composition Di0.50 Jd0.50 was a distinct end member.The boundaries between disordered and ordered phases in the Nybö pyroxenes fall at about 0.35 and 0.65 Jd/(Di+ Jd), in close agreement with the previous TEM investigations.The degree of order varies with composition following a bell-shaped curve: different coaxial bell-shaped curves can be drawn for crystals which have similar compositions but come from different metamorphic environments. The order vs composition diagrams may be useful for the interpretation of the P-T-t histories of the host rocks. 相似文献
15.
超高压榴辉岩中绿辉石组构和变形机制研究进展 总被引：2，自引：0，他引：2
榴辉岩中绿辉石晶格优选方位(LPO)类型主要有S型(压扁型)组构、L型(收缩型)组构、L-S中间型组构、退火型组构,其中L型和S型组构是绿辉石在超高压岩石中最发育的组构类型.矿物组构的产生与变形机制密切相关,目前还无法解释绿辉石LPO产生和变化的原因.对天然绿辉石变形机制的最新研究进行了评述,包括位错蠕变产生变形绿辉石LPO的传统观点,以及扩散蠕变伴随晶体各向异性生长和空间群转换两种新观点.使用费氏台对大别山双河地区榴辉岩中的绿辉石组构进行了测量,并用电子背散射衍射技术(EBSD)对测量结果进行了验证.结合榴辉岩的显微构造和绿辉石组构特征对大别山双河超高压榴辉岩中绿辉石的变形机制进行了初步探讨,认为其变形机制以位错蠕变为主. 相似文献
16.
大别山双河地区超高压变质岩矿物超微构造的HRTEM研究 总被引：3，自引：1，他引：2
报道了大别山双河地区超高压榴辉岩和硬玉石英岩矿物超微构造及缺陷结构的高分辨透射电镜研究结果。在天然变形绿辉石晶内的自由位错、位错倾斜壁、位错环、位错网、亚晶界、堆垛层错等亚构造中 ,发现了纳米级水分子团 ,这种球形状水分子团包体的存在是导致绿辉石晶体水解弱化和塑性变形的重要因素。在榴辉岩矿物中广泛发育的层错、(10 0 )变形双晶、晶畴结构、界面与晶面的交叉滑移、晶格畸变等变形构造及缺陷结构 ,指示超高压岩石经历了快速折返。在硬玉单晶大约 5 0 0nm的微晶畴内 ,发现了C2 /c和P2 1/n两种结构 ,C2 /c结构的晶体学参数对应于硬玉 ,而P2 1/n结构的晶体学参数对应于绿辉石 ,纳米级P2 1/n出溶结构的存在 ,表明在退变质过程中 ,硬玉在纳米尺度上部分转变为绿辉石 ,并且未能达到平衡。也说明在主体岩石的抬升过程中 ,硬玉晶体伴随有复杂的非平衡退变质作用。对于大别山超高压变质岩的p T轨迹描述及其构造解释具有重要意义。 相似文献
17.
THE ALTUN—NORTH QAIDAM ECLOGITE BELT IN WESTERN CHINA—ANOTHER HP-UHP METAMORPHIC BELT TRUNCATED BY LARGE SCALE STRIKE-SLIP FAULT IN CHINA 总被引：1，自引：0，他引：1
THE ALTUN—NORTH QAIDAM ECLOGITE BELT IN WESTERN CHINA—ANOTHER HP-UHP METAMORPHIC BELT TRUNCATED BY LARGE SCALE STRIKE-SLIP FAULT IN CHINA 相似文献
18.
大别山北部榴辉岩的退变质特征及其地质意义 总被引：3，自引：2，他引：3
研究了大别山北部榴辉岩的变质岩岩石学。结果表明，该区榴辉岩相变质作用可分为早期(超高压)和晚期(高压)两个阶段，并在折返过程中形成了一系列特征性的退变质显微构造。其中，退变质结构主要包括：(1)由于压力降低而出溶形成的一些定向针状或叶片状矿物包裹体，如钠质单斜辉石中石英及石榴子石中的金红石、单斜辉石和磷灰石等；(2)冠状体或后成合晶，特别是石榴子石外围发育两期(“双层”)后成合晶；(3)反应边或退变边，如绿辉石的透辉石退变边、透辉石的角闪石退变边和金红石的钛铁矿退变边等。这些退变质结构为本区榴辉岩高级变质岩的快速折返过程和抬升历史提供了强有力的岩石学依据；石榴子石中针状矿物出溶体进一步证明研究区榴辉岩早期经历了超高压变质作用，峰期变质压力应大干4．0GPa，甚至可能达到5～7GPa或更高。 相似文献
19.
MENG Dawei WU Xiuling FAN Xiaoyu ZHANG Zhengjie CHEN Hong MENG Xin ZHENG Jianping 《《地质学报》英文版》2008,82(2):371-376
α-PbO2-type TiO2 （TiO2-Ⅱ） is an important index mineral for ultrahigh-pressure metamorphism. After the discovery of a natural high-pressure phase of titanium oxide with α-PbO2- structure in omphacite from coesite-bearing eclogite at Shima in the Dabie Mountains, China, a nanoscale （〈2 nm） α-PbO2-type TiO2 has been identified through electron diffraction and high-resolution transmission electron microscopy in coesite-bearing jadeite quartzite at Shuanghe in the Dabie Mountains. The crystal structure is orthorhombic with lattice parameters a = 4.58×10-1 nm, b = 5.42×10-1 nm, c = 4.96×10-1 nm and space group Pbcn. The analysis results reveal that ruffle {011}R twin interface is a basic structural unit of α-PbO2-type TiO2. Nucleation of α-PbO2-type TiO2 lamellae is caused by the displacement of one half of the titanium cations within the {011}R twin slab. This displacement reduces the Ti-O-Ti distance and is favored by high pressure. The identification of α- PbO2-type TiO2 in coesite-bearing jadeite quartzite from Shuanghe, Dabie Mountains, provides a new and powerful evidence of ultrahigh-pressure metamorphism at 4--7 GPa, 850℃-900℃, and implies a burial of continental crustal rocks to 130-200 kilometers depth or deeper. The α-PbO2-type TiO2 may be a useful indicator of the pressure and temperature in the diamond stability field. 相似文献
20.
JIAO Shuqiang JIN Zhenmin JIN Shuyan TAN Zishan Department of Environmental Resource Engineering Fuzhou University Fujian Faculty of Earth Sciences China University of Geosciences Wuhan 《《地质学报》英文版》1999,73(4):411-417
The rheological characters of omphacites in Dabie ultra-high-pressure eclogite have been studied interms of fabric, dislocation and micro-structures. 1. The eclogite has undergone high-temperature deformation, thus forming omphacite lattice preferred orientation. In addition to creep dislocation, the omphacite ductile deformation may have other mechanisms, such as diffusion creep and grain boundary migration. 2. The main-phase deformation of eclogite is coaxial, but asymmetry strain also exists due to strain partitioning in the Dabie erogenic belt. 3.The twin measured by the universal stage is (100), indicating that omphacite high-T deformation was superimposed by low-T deformation. 4. Subgrain structure is common in omphacite, but the deformation features of the omphacites in the Shuanghe area and Bixiling area are different, the latter being dominated by dynamic recrystallization. 5. The Flinn plots show that the strain of omphacite belongs to the constriction ellipsoid and stretching strain, which is 相似文献