B-type olivine fabric induced by grain boundary sliding

被引:51
作者
Precigout, Jacques [1 ]
Hirth, Greg [2 ]
机构
[1] Univ Orleans, UMR CNRS 7327, Inst Sci Terre Orleans, F-45067 Orleans, France
[2] Brown Univ, Dept Geol Sci, Providence, RI 02912 USA
关键词
Lattice Preferred Orientation; fabric strength; deformation mechanism; Ronda peridotite; LATTICE-PREFERRED ORIENTATION; RONDA PERIDOTITE; UPPER-MANTLE; MISORIENTATION INDEX; STRAIN LOCALIZATION; DEFORMATION EXPERIMENTS; SEISMIC ANISOTROPY; DIFFUSION CREEP; SIMPLE SHEAR; STRENGTH;
D O I
10.1016/j.epsl.2014.03.052
中图分类号
P3 [地球物理学]; P59 [地球化学];
学科分类号
0708 ; 070902 ;
摘要
Mineral Lattice Preferred Orientation (LPO) in naturally deformed peridotite is typically interpreted to result from the motion of intra-crystalline dislocations during dislocation creep. The degree of mineral alignment (fabric strength) is often assumed to increase with increasing finite strain. Here, we document olivine LPOs in peridotites in a kilometer-scale mantle shear zone in the Ronda massif (Spain) that demonstrate a transition from a flow-parallel [100]-axis LPO (A-type fabric) to a flow-normal [100]-axis LPO (B-type fabric). We conclude that the B-type fabric in the Ronda peridotite results from the enhancement of grain boundary sliding (GBS) with decreasing grain size, rather than a change in the dominant dislocation slip system because: (I) dislocation sub-structures remain consistent with the A-type slip system in all samples; (2) the fabric transition correlates with decreasing fabric strength despite increasing finite strain; (3) the analysis of deformation conditions in Ronda is inconsistent with the experimental conditions, including water content, inferred to promote the dominance of (010)[001] slip in laboratory samples, and (4) our observations are supported by experiments that document B-type fabric in olivine aggregates where deformation involves a component of GBS. Our results have important implications for interpreting the theological properties of shear zones and upper mantle structures via micro-structural and seismic observations. (C) 2014 Elsevier B.V. All rights reserved.
引用
收藏
页码:231 / 240
页数:10
相关论文
共 53 条
  • [21] Shearing Melt Out of the Earth: An Experimentalist's Perspective on the Influence of Deformation on Melt Extraction
    Kohlstedt, David L.
    Holtzman, Benjamin K.
    [J]. ANNUAL REVIEW OF EARTH AND PLANETARY SCIENCES, 2009, 37 : 561 - 593
  • [22] Dynamic recrystallization processes in plagioclase porphyroclasts
    Kruse, R
    Stünitz, H
    Kunze, K
    [J]. JOURNAL OF STRUCTURAL GEOLOGY, 2001, 23 (11) : 1781 - 1802
  • [23] Misorientation analysis and the formation and orientation of subgrain and grain boundaries
    Lloyd, GE
    Farmer, AB
    Mainprice, D
    [J]. TECTONOPHYSICS, 1997, 279 (1-4) : 55 - 78
  • [24] Arc-parallel flow within the mantle wedge: Evidence from the accreted Talkeetna arc, south central Alaska
    Mehl, L
    Hacker, BR
    Hirth, G
    Kelemen, PB
    [J]. JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH, 2003, 108 (B8)
  • [25] Olivine crystals align during diffusion creep of Earth's upper mantle
    Miyazaki, Tomonori
    Sueyoshi, Kenta
    Hiraga, Takehiko
    [J]. NATURE, 2013, 502 (7471) : 321 - +
  • [26] Natural examples of olivine lattice preferred orientation patterns with a flow normal a-axis maximum
    Mizukami, T
    Wallis, SR
    Yamamoto, J
    [J]. NATURE, 2004, 427 (6973) : 432 - 436
  • [27] High pressure and temperature fabric transitions in olivine and variations in upper mantle seismic anisotropy
    Ohuchi, Tomohiro
    Kawazoe, Takaaki
    Nishihara, Yu
    Nishiyama, Norimasa
    Irifune, Tetsuo
    [J]. EARTH AND PLANETARY SCIENCE LETTERS, 2011, 304 (1-2) : 55 - 63
  • [28] Lithospheric shear zones as constant stress experiments
    Platt, J. P.
    Behr, W. M.
    [J]. GEOLOGY, 2011, 39 (02) : 127 - 130
  • [29] Exhumation of the Ronda peridotite and its crustal envelope:: constraints from thermal modelling of a P-T-time array
    Platt, JP
    Argles, TW
    Carter, A
    Kelley, SP
    Whitehouse, MJ
    Lonergan, L
    [J]. JOURNAL OF THE GEOLOGICAL SOCIETY, 2003, 160 : 655 - 676
  • [30] Strain localisation in the subcontinental mantle - a ductile alternative to the brittle mantle
    Precigout, J.
    Gueydan, F.
    Gapais, D.
    Garrido, C. J.
    Essaifi, A.
    [J]. TECTONOPHYSICS, 2007, 445 (3-4) : 318 - 336