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Strukturuntersuchung an einer Hornblende aus dem eklogitischen Gestein von Stramez, s�dliche Koralpe
Abstract
Zusammenfassung Eine Strukturuntersuchung auf Grund zweidimensionaler Fouriermethoden bestätigt für die Hornblende aus dem eklogitischen Gestein von Stramez die vermutete kristallchemische Formel, wobei sich die Position A in 10-Koordination als besetzt erweist. Außerdem ist für die 6-koordinierten Kationen eine nichtstatistische Besetzung der Atomlagen wahrscheinlich.
... All crystallographic calculations and indexing were done with the lattice parameters and equivalent positions reported for a hornblende by Trojer and Walitzi (1965). The lattice parameters are a:0.986 ...
Diffraction-contrast experiments compared with computer simulation of dislocation images confirm that the primary unit Burgers vector in clinoamphibole is [001]. This information, along with operative glide systems and calculated dislocation energies, is considered in order to propose a possible model for the [001] unit Burgers vector in the clinoamphibole structure. -Authors
Summary This document is part of Subvolume G ‘References for III/7’ of Volume 7 ‘Crystal Structure Data of Inorganic Compounds’ of Landolt-Börnstein - Group III Condensed Matter.
Summary This document is part of Subvolume D1b ‘Key Element: Si. Part 2’ of Volume 7 ‘Crystal Structure Data of Inorganic Compounds’ of Landolt-Börnstein - Group III Condensed Matter. Substances contained in this document (element systems and chemical formulae) Al-B-Ca-F-Fe-H-K-Li-Mg-Mn-Na-O-Si-Ti: (K,Na,Ca)(Li,Ca,Mg,Mn,FeII ,FeIII,Al,Ti)3(FeII,Al)6[(BO3)3(Si6O18) Ċ (O,OH,F)4]. Al-B-Ca-F-Fe-H-K-Li-Mg-Na-O-Si-V: (K,Na,Li)(Mg,Ca,Fe)3(Al,V)6 Ċ [(BO3)3(Si6O18)(OH,F)4]. Al-B-Ca-F-Fe-H-Mg-Na-O-Si-Ti: (Na,Ca)(Mg5Fe)3(Al,Ti)6KBO3)3 Ċ (Si6O18)(OH,F)4]. Al-B-Ca-Fe-H-K-Mg-Na-O-Si-Ti: (K,Na,Ca)(Mg,Fe)3(Al,Ti)6 Ċ [(BO3)3(Si6O18)(OH)4]. Al-B-Ca-Fe-H-O-R-Si-Y: (Ca,Y,R)12(Al,FeIII)2[Si8B8O40 Ċ (OH)8]. Al-B-Ca-H-O-Si-Y: (Ca,Y)2(Al,B,Si)3O8 Ċ H2O. Al-B-F-Fe-H-Mg-O-Si: Mg(Mg,Fe,Al)3Al6[(BO3)3 Ċ (Si6O18)(O,OH,F)4]. Al-B-Fe-H-Mg-O-Si: Mg(Mg,Fe)3(Al,Fe)6[(BO3)3 Ċ (Si6O18)(O,OH)4]. Al-B-Fe-H-Na-O-Si: NaFe3 IIAl6[(BO3)3(Si6O18)(OH)4]. Al-Be-Ca-Cl-Fe-H-K-Mg-Mn-Na-O-Pb-Si: (Pb,Ca,Mn,Na,K)24(FeIII,Al,Mg)8 Ċ (Si,Al,Be)27O84(OH,Cl)8. Al-Ca-Ce-Fe-H-Mg-O-Si: Ca10(Mg,Fe)2(Al,Fe,Ce)4[(Si9O34)·(OH)4]. Al-Ca-Ce-Fe-H-O-P-Si: (Ca,Ce)2Al2(FeII,FeIII,Al) Ċ [(Si,P)3O12(OH)]. Al-Ca-Ce-Fe-H-O-Si: (Ca,Ce)2Al2(FeII,FeIII)[Si3O12·(OH)]. Al-Ca-Cl-Fe-H-K-Mg-Mn-Na-Nb-O-R-Si-Sr-Ti-Zr: [(K,Na,Ca,Sr,R)21···22(Zr,FeII,FeIII,Mn,Mg,Ti,Al,Nb)6Si25...26 Ċ O75...76(OH,C1)4]. Al-Ca-Cr-F-Fe-H-K-Na-O-Si: (K,Na,Ca)(Al,Cr,FeII,FeIII)2 Ċ [AlSi3O10(OH5F)2]. Al-Ca-F-Fe-H-K-Mg-Na-O-Si-Ti: (K,Na)Ca2(Mg,FeII,FeIII)4Ti Ċ [(Al2Si6O22)(O,OH,F)2]. Al-Ca-F-Fe-H-K-Mg-Na-O-Si: (K,Na)0,5...1,0Ca2(Mg,FeII)3...4 Ċ (FeIII,Al)2...1[Al2Si6O22 Ċ (O,OH,F)2]. Al-Ca-Fe-H-K-Mg-Mn-Na-O-Si-Ti: (K,Na,Ca)2(Mg,FeII,Ti,Mn)3 Ċ (Al,FeIII)2[Al2Si6O22(OH)2]. Al-Ca-Fe-H-K-Mg-Mn-Na-O-Si-Ti: (K,Na,Ca)3(Mg,FeII,FeIII,Al,Mn,Ti)5[(Al,Si)8(O,OH)24]. Al-Ca-Fe-H-K-Mg-Mn-Na-O-Si-Ti: (K,Na,Ca)>2(Mg,FeII,Mn)>3 Ċ (FeIII,Ti,Al) <2[(Al,Si)8O22·(O,OH)2]. Al-Ca-Fe-H-K-Mg-Na-O-Si-Ti: (K,Na)(Na,Ca)2(Mg,Fe,Al,Ti)5 Ċ [(Al,Si)8O22(O,OH)2]. Al-Ca-Fe-H-K-Mg-Na-O-Si-Ti: (K,Na,Ca)(Mg,Fe,Al)2[Al Ċ (Si,Ti)3O10(OH)2]. Al-Ca-Fe-H-K-Mg-Na-O-Si: (K,Na,Ca)2(Mg,FeII)3(Al,FeIII)2·[Al2Si6O22(OH)2]. Al-Ca-Fe-H-K-Mg-Na-O-Si: (K,Na,Ca)<1(Al,Fe,Mg)2·[Al0,35Si3,65O10(OH)2]. Al-Ca-Fe-H-Mg-Mn-Na-O-Si: (Na,Ca,Mn,Mg,Fe)6,09[(Al,Si)7,99 Ċ O22(OH)2]. Al-Ca-Fe-H-Mg-O-Si-Ti: (Ca,Mg)3(Fe,Al,Ti)2[(SiO4)3-x·(OH)4x. Al-Ca-Fe-H-Mg-O-Si: Ca2Mg3Fe1,5...2[(Al,Fe)Si7O22 Ċ (O,OH)2]. Al-Ca-Fe-K-Mg-Na-O-Si-Ti: (K,Na)Ca2(Mg,FeII,FeIII)4Ti Ċ [(Al2Si6O22)(O2$-$)2]. Al-Cr-Fe-H-Mg-O-Si: Mg5(Fe,Cr,Al)[AlSi3O10(OH)2] Ċ (OH)6. Al-Cr-H-Mg-O-Si: {(Mg,Al)<3[(Cr,Al)Si3O10(OH)2]} · [Mg3(OH)6]. Al-Fe-H-Mg-Mn-O-Si-Ti: (Mg,Mn,Fe)7[(Al,Ti,Si)8O22 Ċ (O,OH)2]. Al-Fe-H-Mn-O-Si: (Mn,Al,Fe)6[(Al,Si)Si3O10(OH)8]. B-Ca-H-O-Si-Y-Yb: Ca3(Y,Yb)4B4Si6O27 · 3H2O. Ba-Ca-Fe-H-Mg-O-Pb-Si: (Ba,Ca,Mg,Pb,FeII)7FeIII[Si3O6 Ċ (O,OH)6]2. Ba-Fe-H-Mg-O-Si-Ti: Ba2(Fe,Ti,Mg)2H2[O2(Si4O12)]. Ba-Fe-H-Mg-O-Si-Ti: Ba2(Mg,FeII,FeIII,Ti)2[Si4O12 Ċ (OH)2]. Ba-Fe-H-Mg-O-Si-Ti: Ba2(Mg,FeII,FeIII,Ti)2[Si4O13] Ċ H2O. Ba-Fe-H-Mn-O-Si: BaMn2FeIII[(Si2O7)O(OH)] (I). Ba-Fe-H-Mn-O-Si: BaMn2FeIII[(Si2O7)O(OH)] (II). Bi-Fe-H-O-Si: Fe2Bi[(SiO4)2(OH)]. Ca-Cl-Fe-H-Mg-Mn-Na-Nb-O-R-Si-Zr: Na12(Ca,R)6(FeII,FeIII,Mn,Mg)3 Ċ Zr3(Zr,Nb)x[Si9O27-y(OH)y]2 Ċ [Si3O9]2Clz. Ca-Cl-Fe-H-Mg-Mn-Na-O-R-Si-Zr: Na4(Ca,R)2(Mg,Mn,Fe)Zr[Si8O22 Ċ (OH,Cl)2]. Ca-Cl-Fe-H-Mn-O-Si-Zn: (Fe,Mn,Ca,Zn)8[Si6O15(OH,Cl)10]. Ca-Cl-Fe-H-Na-O-Si-Zr: (Na,Ca,Fe)6Zr[(Si6O18)(OH,Cl)]. Ca-Cr-Fe-H-O-Si: Ca3(FeIII,CrIII)2[(SiO4)2(OH)4]. Ca-F-Fe-H-Mg-Mn-Ni-O-Si-Ti: (Ca,Mg,Mn,Fe,Ni,Ti)9[(SiO4)4 Ċ (O,OH,F)2]. Ca-F-Fe-H-Mg-Mn-O-Si-Zn: (Zn,Ca,Mg,Mn,Fe)7[Si4O11 · (OH,F)]2. Ca-Fe-H-K-Na-O-Si-Ti: K2Na(Ca,FeII)2(Ti,FeIII)[Si7019 Ċ (OH)]. Ca-Fe-H-Mg-Mn-Na-O-Si: (Na,Ca,Mn,Mg,Fe)7[Si4O11(OH)]2. Ca-Fe-H-Mg-O-Sb-Si: Ca2(Mg,Fe)4Sb[(Si4O12)(OH)8]. Ca-Fe-H-Na-O-Si-Zr: Na12Ca6Fe3Zr3[Si3O9]2[Si9O24 Ċ (OH)3]2. Ca-Fe-H-Na-O-Si-Zr: Na4Ca2FeZr[Si8O22(OH)2]. Ca-Fe-H-O-Si-Ti: Ca3(TiFe)[(FeO4)(SiO4)2-x(OH)4x]. Ca-Fe-H-O-Si-Zr: Ca3(Zr,Fe)[(FeO4)(SiO4)2-x Ċ (OH)4x]. Ca-H-K-Na-O-Si-Ti: K2NaCa2Ti[Si7O19(OH)]. Cl-Fe-H-Mg-Mn-O-Si: (Mn6,2Fe1,5Mg0,3)[Si6O15 Ċ (OH,Cl)10]. Cl-Fe-H-Mn-O-Si: (Mn,Fe)8[Si6O15(OH,Cl)10] (I). Cl-Fe-H-Mn-O-Si: (Mn,Fe)8[Si6O15(OH,Cl)10] (II). Cl-Fe-H-O-Pb-Si: Pb8Fe3 IIIKSi3O9)(OH,Cl)]3. F-Fe-H-Mg-O-Si-Ti: (Mg.Fe,Ti)9[(SiO4)4(O,OH,F)2]. Fe-Gd-H-O-Si: Fe2Gd7[Si6O23(OH)3]. Fe-Gd-H-O-Si: Fe2Gd8Si7O28 Ċ 3H2O. Fe-H-La-O-Si: Fe2La7[Si6O23(OH)3]. Fe-H-La-O-Si: Fe2La8Si7O28· 3H2O. Fe-H-Mg-Mn-Ni-O-Si-Ti: (Mg,Mn,Fe,Ni,Ti)5[(SiO4)2 Ċ (O,OH)2]. Fe-H-Mg-Mn-O-Si-Zn: (Zn,Mg,Mn,Fe)7[Si4O11(OH)]2. Fe-H-Mg-Mn-O-Si: (Mg,Mn,Fe)6[(Si,FeIII)Si3O10 Ċ (0,OH)8]. Fe-H-Mg-Mn-O-Si: (Mg,Mn,Fe)7[Si4O11(OH)]2. Fe-H-Mg-O-Si-Ti: (Mg,Fe,Ti)5[(SiO4)2(O,OH)2]. Fe-H-Nd-O-Si: Fe2Nd7[Si6O23(OH)3]. Fe-H-Nd-O-Si: Fe2Nd8Si7O28· 3H2O. Fe-H-O-Sb-Si: Fe2Sb[(SiO4)2(OH)]. Fe-H-O-Si-Sm: Fe2Sm7[Si6O23(OH)3]. Fe-H-O-Si-Sm: Fe2Sm8Si7O28 · 3H2O.
The crystal structure of the basaltic clino-amphibole magnesio-hastingsite was refined from three-dimensional photographic X-ray data by a full matrix least-squares method in the space group C2/m. The final conventional R-factor for 1191 observed non-equivalent reflections was 4.7%. Besides chemical composition and cell parameters optical data were determined. The A-site is positionally disordered in two sites, one on the mirror plane and the other on the 2-fold axis. Coordination numbers round A and cation distributions in M(1), M(2), M(3), T(1), T(2) are discussed.
The crystal structures of magnesiosadanagaite (MS) from Mogok, Myanmar, monoclinic, a 9.857(2), b 17.899(4), c 5.318(1) Å, β 105.36(1)°, V 904.74(8) Å3, C2/m, Z = 2, and potassic-ferrisadanagaite (FS) from the Ilmen alkaline massif, South Urals, Russia, a 9.9257(4), b 18.0917(7), c 5.3709(2) Å, β 105.19(1)°, V 930.75(2) Å3, C2/m, Z = 2, have been refined to R values of ~3% using single-crystal MoKα X-ray data. The crystals used in the collection of the intensity data were subsequently analyzed by electron-microprobe
techniques, leading to the following compositions: MS: (Na0.82 K0.17) (Ca1.95 Na0.05) (Mg3.36 Fe2+0.23 Al1.20 Cr3+0.07 Ti4+0.16) (Si5.47 Al2.53) O22 [(OH)1.58 F0.42]; FS: (Na0.31 K0.62) (Ca1.72 Na0.28) (Mg0.56 Fe2+2.12 Mn2+0.26 Zn0.02 Al0.72 Fe3+1.07 Ti4+0.21) (Si5.24 Al2.76) O22 [(OH)1.70 F0.30]. Site populations were assigned from the results of site-scattering refinement and stereochemical analysis, taking into
account the unit formula determined for each crystal. The <T–O> distances, 1.678 and 1.684 Å, indicate that [4]Al is strongly ordered at the T(1) site in each crystal, but the <T(2)–O> distances, 1.648 and 1.655 Å, indicate significant Al at the T(2) site. The Fe2+ and Fe3+ contents in each crystal were assigned from the <M–O> distances. The A(2) and A(m) sites are occupied by Na and (Na,K), respectively, in crystal MS, and by Na and K, respectively, in crystal FS. Both amphiboles
show SRO (short-range order) of species at the M(4), O(3), A(m) and A(2) sites, and the relative abundances of these arrangements were assigned.
Neutron texture analyses of quartz-bearing and quartz-free amphibolite mylonites from the Windy Pass thrust, Cascades Crystalline Core (Washington/USA) reveal pronounced textures of plagioclase and clino-amphiboles (hornblende, cummingtonite) but no preferred orientation of quartz. A reliable strategy for amphibolite fabric analysis is presented by a systematic analytical approach to the experimental diffraction data processing. Clino-amphiboles show transitional textures between ideal single crystal orientations and axial symmetric great circle distributions. Plagioclase reveals a-axes distributions scattering along a great circle approximating the foliation plane as well as a-axes maxima close to the macroscopic lineation. Correlation of the textures with grain shape anisotropies of hornblende and plagioclase and comparison with data from the literature suggest that the texture variations are due to different strain regimes rather than due to different crystallographic reorientation mechanisms. The kinematic directions deduced from the microfabric correlate well with the regional tectonic interpretations. In contrast, individual deformation paths are not yet established for the different tectonic units, as the significance of the separating Windy Pass thrust requires further structural analysis and fabric studies.
The microstructure in hornblende of a dynamically recrystallized amphibolite from a high temperature shear zone is investigated by conventional and high resolution transmission electron microscopy in order to get information on the mechanical behaviour of this lower crustal rock. The microstructure is typical for dislocation creep consisting of subgrain boundaries and free dislocations. The primary slip system is (100) [001], secondary slip systems are (010) [100] and {110} 1/2 <110>. Dislocations with [001] Burgers vector are dissociated on (100). Dissociation of [100] and 1/2 <110> dislocations produces planar faults on (010) representing chain multiplicity faults with pyroxene or sheet silicate character. They are obstacles for dislocation motion on the primary slip plane. Helix formation indicates cross slip of [001] screw dislocations. Climb of [100] and 1/2 <110> edge dislocations leads to low-angle tilt boundaries with [001] tilt axis. Paleostress and strain rate estimates for lower crustal shear zones in amphibolites based on dynamically recrystallized grain size are in the order of 100 MPa and 10(-10) S-1, respectively.
Inhalt Auf Grund einer chemischen Analyse und einer Strukturuntersuchung mit Hilfe einer Fourieranalyse kann die spezielle kristallchemische Formel der basaltischen Hornblende vom Kuruzzenkogel geschrieben werden:
Die basaltische Hornblende von Černošin, ČSR, wird optisch, chemisch und röntgenographisch untersucht.
Die Besetzung einzelner Positionen mehrerer Hornblenden wird durch Auszählen der Elektronen aus den Fourierprojektionen kontrolliert.
Inhalt Hornblenden aus Eklogiten und Amphiboliten der südlichen Koralpe werden chemisch und optisch untersucht; außerdem sind die Gitterkonstanten der Hornblenden bestimmt worden.
Bolivian crocidolite, a fibrous amphibole, is shown to contain fibres approximating to single crystals. The structure, which is determined by standard methods leading to a Fourier projection on (001), is shown to be generally similar to that of tremolite. The more precise determination reveals certain departures from that structure however. The silicate chain is found to bend away from the plane of the metal ions in a lateral direction. The Si—O bond length when the oxygen atom is bonded to one silicon atom only is found to be less than that when the oxygen atom is bonded to two silicon atoms. The distribution of the magnesium and iron atoms among the available atomic sites is found to be non-uniform and is discussed with reference to the charge distribution.
To determine the nature of the Mg-Fe distribution in the four different metal positions in ferromagnesian amphiboles, the crystal structure of a grunerite, with about 30 mole per cent of the Mg component, has been determined and refined by the least-squares method. It is found that Mg and Fe are randomly distributed in three metal positions, while the fourth metal position is mainly occupied by Fe atoms.
In a crystal without symmetry elements and containing a sufficiently large number of atoms the probability of the hkl reflexion having an intensity between I and I + dI is P(I) dI, where P(I) = Σ−1 exp{−I/Σ}, and Σ is the sum of the squares of the scattering factors of the atoms. In a centrosymmetric crystal the probability of the structure amplitude of the hkl reflexion lying between F and F + dF is P(F) dF, where P(F) = (2πΣ)½ exp{−F2/2Σ}, a result noticed empirically. In a centred crystal (k−1)/k of the reflexions are zero, and the remaining 1/k of them are distributed like those of an uncentred crystal with parameterkΣ, where k is 4 for face-centring and 2 for end- or body-centring. Other symmetry elements do not produce important effects on the general reflexions, but may make a zone or line of intensities behave as if centred or centrosymmetric. The mean value of I is Σ, a fact that can be used to put relative intensities on an absolute basis. The mean values of |F| or I2 can also be used, but the mean value of I is the only one independent of the symmetry. The difference between the ratios of 〈|F|〉2 or 〈I〉 for centrosymmetric and noncentrosymmetric crystals may serve for the purely X-ray determination of a centre of symmetry.
The basic problem of structure determination in x ray crystallography is described together with the methods available up to 1948 - primarily the Patterson, isomorphous replacement and heavy-atom methods. In 1948 inequality relationships were derived by Harker and Kasper but these could only give a solution for very simple structures. A breakthrough came in 1952 with the introduction of the triple-product sign relationship, which could only be applied to centrosymmetric structures. In 1955 Cochran showed that the general-valued phases for non-centrosymmetric structures were also related. After several years, during which a number of more-or-less involved methods were proposed for applying sign relationships, it was shown by Karle and Karle that a comparatively simple approach, the symbolic addition method, could be applied even to complex structures. A variant of the method is also applicable to non-centrosymmetric structures. A different technique of applying phase relationships, developed by Germain, Main and Woolfson has been fully automated and quite complex structures can now be solved with computer programmes which require as input only unprocessed observed data. Some future trends in the development of direct methods may be seen in present work in the use of inequalities involving determinants of high rank and also in methods which attempt to derive values of certain types of structure-invariant quantities.
Es werden Kluftkarinthine von der Saualpe in Krnten kristallo-graphisch, optisch, chemisch und rntgenographisch untersucht.In der Literatur unterscheidet man zwischen Gesteinskarinthin und Kluftkarinthin. Whrend der Gesteinskarinthin schon eingehend untersucht worden ist (S. Koritnig, 1940,H. Heritsch, P. Paulitsch, undE.-M. Walitzi, 1957), war es das Ziel der vorliegenden Arbeit, dasselbe am Kluftkarinthin durchzufhren.Nach den jetzt vorliegenden Daten liegt der Gesteinskarintin innerhalb des Bereiches der Hornblende sowohl optisch wie auch chemisch (durch Eisenarmut und Magnesiumreichtum) am weitesten von der gemeinen grnen Hornblende ab. Die beiden untersuchten Kluftkarinthine bilden in denselben Eigenschaften bergnge zur gemeinen grnen Hornblende.Unter Bercksichtigung der rntgenographischen Untersuchung lauten die speziellen kristallchemischen Formeln frKluftkarinthin Saualpe
Kluftkarinthin Kupplerbrunn
Koralpenkristallin der Geol. Spezialkarte der Republik �sterreich
- A Kieslinger
- A. J. C. Wilson