Relation between mantle shear zone deformation and metasomatism in spinel peridotite xenoliths of Jeju Island (South Korea): Evidence from olivine CPO and trace elements

Journal of Geodynamics

Volumn 50, Issue 5, 2010, Pages 424-440

  Yang, K ^a   Hidas, K ^b   Falus, G ^c   Szabo C ^a,b   Nam, B ^a   Kovacs I ^c   Hwang, B ^a  

^a Pusan National University   (South Korea)

^b EÖTVÖS LORÁND UNIVERSITY   (Hungary)

^c GEOLOGICAL AND GEOPHYSICAL INSTITUTE OF HUNGARY   (Hungary)

Author keywords

Coarse grained; CPO; Deformation; Jeju Island (South Korea); Mantle shear zone; Metasomatism; Mylonitic peridotites; Porphyroclastic

Indexed keywords

CHEMICAL ANALYSIS; DEFORMATION MECHANISM; ENRICHMENT; LITHOSPHERIC STRUCTURE; MANTLE STRUCTURE; METAIGNEOUS ROCK; METASOMATISM; MYLONITE; PERIDOTITE; PETROFABRIC; RARE EARTH ELEMENT; SHEAR ZONE; SPINEL; TRACE ELEMENT; XENOLITH;

CHEJU [SOUTH KOREA]; SOUTH KOREA;

EID: 77957919775     PISSN: 02643707     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.jog.2010.05.005     Document Type: Article

References (116)

1. Abramson E.H., Brown J.M., Slutsky L.J., Zaug J. The elastic constants of San Carlos olivine to 17GPa. Journal of Geophysical Research-Solid Earth 1997, 102:12253-12263.
2. Arai S. Compositional variation of olivine-chromian spinel in Mg-rich magmas as a guide to their residual spinel peridotites. Journal of Volcanology and Geothermal Research 1994, 59:279-293.
3. Avé Lallemant H., Carter N. Syntectonic recrystallization of olivine and modes of flow in the upper mantle. Bulletin of the Geological Society of America 1970, 81:2203-2220.
4. Bali E., Falus G., Szabó C., Peate D.W., Hidas K., Torok K., Ntaflos T. Remnants of boninitic melts in the upper mantle beneath the central Pannonian Basin?. Mineralogy and Petrology 2007, 90:51-72.
5. Ben Ismail W., Mainprice D. An olivine fabric database: an overview of upper mantle fabrics and seismic anisotropy. Tectonophysics 1998, 296:145-157.
6. Bodinier J.L., Vasseur G., Vernieres J., Dupuy C., Fabries J. Mechanisms of mantle metasomatism: geochemical evidence from the Lherz orogenic peridotite. Journal of Petrology 1990, 31:597-628.
7. Brey G.P., Köhler T.P. Geothermobarometry in four phase lherzolites. II. New thermobarometers and practical assessment of existing thermobarometers. Journal of Petrology 1990, 31:1353-1378.
8. Bunge H.J. Texture Analysis in Materials Sciences 1982, Buttleworth, London.
9. Bussod G., Christie J. Textural development and melt topology in spinel lherzolite experimentally deformed at hypersolidus conditions. Journal of Petrology Special Lherzolite Issue 1991, 17-39.
10. Castle J.C., Creager K.C. NW Pacific slab rheology, the seismicity cutoff, and the olivine to spinel phase change. Earth Planets Space 1998, 50:977-985.
11. Castle J.C., Creager K.C. Topography of the 660-km seismic discontinuity beneath Izu-Bonin: implications for tectonic history slab deformation. Journal of Geophysical Research-Solid Earth 1998, 103:12511-12527.
12. Chai M., Brown J.M., Slutsky L.J. The elastic constants of an aluminous orthopyroxene to 12.5GPa. Journal of Geophysical Research-Solid Earth 1997, 102:14779-14785.
13. Chalot-Prat F., Boullier A.M. Metasomatism in the subcontinental mantle beneath the Eastern Carpathians (Romania): new evidence from trace element geochemistry. Contributions to Mineralogy and Petrology 1997, 129:284-307.
14. Chang L.J., Wang C.Y., Ding Z.F. Seismic anisotropy of upper mantle in eastern China. Science in China Series D-Earth Sciences 2009, 52:774-783.
15. Chen B., Jahn B.M., Zhai M. Sr-Nd isotopic characteristics of the Mesozoic magmatism in the Taihang-Yanshan orogen, North China craton, and implications for Archaean lithosphere thinning. Journal of the Geological Society 2003, 160:963-970.
16. Choi S.H. Geochemical Study of Ultramafic Xenoliths in Basalts from Cheju Island, Korea 1998, Seoul National University, Seoul, p. 216.
17. Choi S.H. Oxidation state of mantle xenoliths from Jeju-do, South Korea. Geosciences Journal 2000, 4:211-220.
18. Choi S.H., Jwa Y.J., Lee H.Y. Geothermal gradient of the upper mantle beneath Jeju Island, Korea: evidence from mantle xenoliths. Island Arc 2001, 10:175-193.
19. Choi S.H., Lee J.I., Park C.H., Moutte J. Geochemistry of peridotite xenoliths in alkali basalts from Jeju Island, Korea. Island Arc 2002, 11:221-235.
20. Chough S.K., Kwon S.T., Ree J.H., Choi D.K. Tectonic and sedimentary evolution of the Korean peninsula: a review and new view. Earth-Science Reviews 2000, 52:175-235.
21. Collins M.D., Brown J.M. Elasticity of an upper mantle clinopyroxene. Physics and Chemistry of Minerals 1998, 26:7-13.
22. Downes H. Deformation and geochemical enrichment in spinel peridotites - evidence for mantle shear zones. Chemical Geology 1988, 70:48-148.
23. Downes H. Shear zones in the upper mantle - relation between geochemical enrichment and deformation in mantle peridotites. Geology 1990, 18:374-377.
24. Downes H. Formation and modification of the shallow sub-continental lithospheric mantle: a review of geochemical evidence from ultramafic xenolith suites and tectonically emplaced ultramafic massifs of western and central Europe. Journal of Petrology 2001, 42:233-250.
25. Downes H., Embey-Isztin A., Thirlwall M.F. Petrology and geochemistry of spinel peridotite xenoliths from the western Pannonian Basin (Hungary) - evidence for an association between enrichment and texture in the upper mantle. Contributions to Mineralogy and Petrology 1992, 109:340-354.
26. Engebretson, D., Cox, A., Gordon, R., 1985. Relative motions between oceanic and continental plates in the Pacific Basin. Geological Society of America Special Issue Papers, 206.
27. Fabries J., Lorand J.P., Bodinier J.L. Petrogenetic evolution of orogenic lherzolite massifs in the central and western Pyrenees. Tectonophysics 1998, 292:145-167.
28. Falus G., Tommasi A., Ingrin J., Szabó C. Deformation and seismic anisotropy of the lithospheric mantle in the southeastern Carpathians inferred from the study of mantle xenoliths. Earth and Planetary Science Letters 2008, 272:50-64.
29. Fischer K.M., Fouch M.J., Wiens D.A., Boettcher M.S. Anisotropy and flow in Pacific subduction zone back-arcs. Pure and Applied Geophysics 1998, 151:463-475.
30. Fouch M.J., Fischer K.M. Mantle anisotropy beneath northwest Pacific subduction zones. Journal of Geophysical Research-Solid Earth 1996, 101:15987-16002.
31. Frey F.A., Prinz M. Ultramafic inclusions from San Carlos, Arizona: petrologic and geochemical data bearing on their petrogenesis. Earth and Planetary Science Letters 1978, 38:129-176.
32. Gao S., Rudnick R.L., Yuan H.L., Liu X.M., Liu Y.S., Xu W.L., Ling W.L., Ayers J., Wang X.C., Wang Q.H. Recycling lower continental crust in the North China craton. Nature 2004, 432:892-897.
33. Garrido C.J., Bodinier J.L. Diversity of mafic rocks in the Ronda peridotite: evidence for pervasive melt-rock reaction during heating of subcontinental lithosphere by upwelling asthenosphere. Journal of Petrology 1999, 40:729-754.
34. Griffin W., O'Reilly S., Ryan C. The composition and origin of subcontinental lithospheric mantle. Mantle Petrology: Field Observation and High-Pressure Experimentation: A Tribute to Francis R. (Joe) Boyd 1999, 13-45. The Geochemical Society, Houston. Y. Fei, C. Bertka, B. Mysen (Eds.).
35. Harte B., Cox K., Gurney J. Petrography and geological history of upper mantle xenoliths from the Matsoku kimberlite pipe. Physics and Chemistry of the Earth, First International Conference on Kimberlites 1975, 477-506. Pergamon Press, Oxford.
36. Hidas, K., 2009. Deformation and metasomatism in the sub-continental lithospheric mantle of the Carpathian-Pannonian region (Hungary) and Jeju Island (South Korea). PhD Thesis. Department of Petrology and Geochemistry. Eotvos University Budapest, Hungary, Budapest, p. 172.
37. Hidas K., Falus G., Szabó C., Szabo P.J., Kovács I., Foldes T. Geodynamic implications of flattened tabular equigranular textured peridotites from the Bakony-Balaton Highland Volcanic Field (Western Hungary). Journal of Geodynamics 2007, 43:484-503.
38. Hirth G., Kohlstedt D. Rheology of the upper mantle and the mantle wedge: a view from the experimentalists. Inside the Subduction Factory 2003, 83-105. Geophysical Monograph, American Geophysical Union. J.M. Eiler (Ed.).
39. James D.E., Boyd F.R., Schutt D., Bell D., Carlson R. Xenolith constraints in seismic velocities in the upper mantle beneath southern Africa. Geochemistry Geophysics Geosystems 2004, 5:1-32.
40. Jung H., Karato S.-I. Water-induced fabric transitions in olivine. Science 2001, 293:1460-1463.
41. Kang T.S., Shin J.S. Shear-wave splitting beneath southern Korea and its tectonic implication. Tectonophysics 2009, 471:232-239.
42. Karato S., Jung H., Katayama I., Skemer P. Geodynamic significance of seismic anisotropy of the upper mantle: new insights from laboratory studies. Annual Review of Earth and Planetary Sciences 2008, 36:59-95.
43. Karato S., Zhang S., Zimmerman M.E., Daines M.J., Kohlstedt D.L. Experimental studies of shear deformation of mantle materials: towards structural geology of the mantle. Pure and Applied Geophysics 1998, 150:589-603.
44. Katayama I., Jung H., Karato S.-I. New type of olivine fabric from deformation experiments at modest water content and low stress. Geology 2004, 32:1045-1048.
45. Kelemen P.B., Dick H.J.B. Focused melt flow and localized deformation in the upper mantle - juxtaposition of replacive dunite and ductile shear zones in the Josephine Peridotite, SW Oregon. Journal of Geophysical Research-Solid Earth 1995, 100:423-438.
46. Kelemen P.B., Dick H.J.B., Quick J.E. Formation of harzburgite by pervasive melt/rock reaction in the upper mantle. Nature 1992, 358:635-641.
47. Kennett J.P., McBirney A.R., Thunell R.C. Episodes of Cenozoic volcanism in Circum-Pacific region. Journal of Volcanology and Geothermal Research 1977, 2:145-163.
48. Kim H.C. Interpretation of Geothermal Anomaly Using Heat Flow and Geologic Data in South Korea 2004, Chungnam National University, Daejeon, South Korea, p. 179.
49. Kim J.H. Mesozoic tectonics in Korea. Journal of Southeast Asian Earth Sciences 1996, 13:251-265.
50. Kim K., Nagao K., Suzuki K., Tanaka T., Park E. Evidences of the presence of old continental basement in Jeju volcanic island, South Korea, revealed by radiometric ages and Nd-Sr isotopes of granitic rocks. Journal of Geochemical Exploration 2003, 36:421-441.
51. Kovács I. Water in Nominally Anhydrous Minerals of the Upper Mantle: Experimental and Analytical Developments 2008, Research School of Earth Sciences, The Australian National University, Canberra, p. 224.
52. Le Roux V., Bodinier J.L., Tommasi A., Alard O., Dautria J.M., Vauchez A., Riches A.J.V. The Lherz spinel lherzolite: refertilized rather than pristine mantle. Earth and Planetary Science Letters 2007, 259:599-612.
53. Le Roux V., Tommasi A., Vauchez A. Feedback between melt percolation and deformation in an exhumed lithosphere-asthenosphere boundary. Earth and Planetary Science Letters 2008, 274:401-413.
54. Lee M.W. Petrology and geochemistry of Judu volcanic island, Korea. Science Reports of the Research Institutes Tohoku University Series A 1982, 3:177-256.
55. Lenoir X., Garrido C.J., Bodinier J.L., Dautria J.M., Gervilla F. The recrystallization front of the Ronda peridotite: evidence for melting and thermal erosion of subcontinental lithospheric mantle beneath the Alboran basin. Journal of Petrology 2001, 1:141-158.
56. Li C.F., Chen B., Zhou Z.Y. Deep crustal structures of eastern China and adjacent seas revealed by magnetic data. Science in China Series D-Earth Sciences 2009, 52:984-993.
57. Liu G.D. The Geological and Geophysical Map of China's Seas and Adjacent Areas 1993, Geological Publishing House, Beijing.
58. Liu G.D. Geodynamical evolution and tectonic framework of China. Earth Science Frontiers 2007, 14:39-46.
59. Lloyd G.E., Farmer A.B., Mainprice D. Misorientation analysis and the formation and orientation of subgrain and grain boundaries. Tectonophysics 1997, 279:55-78.
60. Long M.D., van der Hilst R.D. Shear wave splitting from local events beneath the Ryukyu arc: trench-parallel anisotropy in the mantle wedge. Physics of the Earth and Planetary Interiors 2006, 155:300-312.
61. Mainprice, D., 2003. " SuperJ7" and " SuperJctf" - incremental evaluation of J index and J at total grain or orientation count, 28/01/2003 ed.
62. Mainprice, D., 2005a. " ANISch5" - calculating seismic properties from Channel5.
63. Mainprice, D., 2005b. " PFch5" - plotting pole figures from HKLtechnology Channel5 export file, 27/07/2005 ed.
64. Mainprice, D., 2005c. " ROTctf" - rotates Euler angles of ctf files from Channel5.
65. Mainprice, D., 2005d. " VpG" - plotting seismic properties as postscript files from VpG file from ANIS2k, ANISch4 or ANISch5.
66. Mainprice, D., 2007. " PF_PC" - plotting pole figures as postcript files from files of Bunge or Roe Euler angles.
67. Mainprice D., Silver P.G. Interpretation of SkS-waves using samples from the subcontinental lithosphere. Physics of the Earth and Planetary Interiors 1993, 78:257-280.
68. McDonough W.F., Sun S.S. The composition of the Earth. Chemical Geology 1995, 120:223-253.
69. Mercier J.C.C., Nicolas A. Textures and fabrics of upper-mantle peridotites as illustrated by xenoliths from basalts. Journal of Petrology 1975, 16:454-487.
70. Mukasa S.B., Shervais J.W. Growth of subcontinental lithosphere: evidence from repeated dike injections in the Balmuccia lherzolite massif Italian Alps. Lithos 1999, 48:287-316.
71. Mutchler S.R., Fedele L., Bodnar R.J. Analysis Management System (AMS) for reduction of laser ablation ICPMS data. Laser-Ablation-ICPMS in the Earth Sciences: Current Practices and Outstanding Issues 2008, 318-327. Mineralogical Association of Canada Short Course Series. P. Sylvester (Ed.).
72. Nakamura E., Campbell I.H., McCulloch M.T., Sun S.S. Chemical geodynamics in a back arc region around the Sea of Japan - implications for the genesis of alkaline basalts in Japan, Korea, and China. Journal of Geophysical Research-Solid Earth and Planets 1989, 94:4634-4654.
73. Nakamura N. Determination of REE, Ba, Fe, Mg, Na and K in carbonaceous and ordinary chondrites. Geochimica et Cosmochimica Acta 1974, 38:757-775.
74. 2O-deficient, continuous net transfer reaction. Tectonophysics 1999, 303:193-222.
75. Nicolas, A., Christensen, N., 1987. Formation of anisotropy in upper mantle peridotites-a review. In: Fuchs, K., Froidevaux, C. (Eds.), Composition, Structure and Dynamics of the Lithosphere-Asthenosphere System (Geodynamics Series), pp. 111-123.
76. Nicolas A., Lucazeau F., Bayer R. Peridotite xenoliths in Massif Central basalts: textural and geophysical evidence for asthenospheric diapirism. Mantle Xenoliths 1987, 563-574. Wiley and Sons, Chichester, England. P.H. Nixon (Ed.).
77. Otofuji Y., Matsuda T., Nohda S. Paleomagnetic evidence for the Miocene counter-clockwise rotation of northeast Japan - rifting process of the Japan arc. Earth and Planetary Science Letters 1985, 75:265-277.
78. Otsuki K. Plate tectonics of eastern Eurasia in the light of fault systems. Tohoku University Science Report, 2nd Series (Geology) 1985, 55:141-251.
79. Park J., Kwon S.T. Geochemical evolution of the Cheju volcanic island (II): trace element chemistry of volcanic rocks from the northern part of Cheju Island. Journal of Geological Society of Korea 1993, 29:477-492.
80. Park J., Kwon S.T. Mineral chemistry of the volcanic rocks from the northern part of Cheju Island. Journal of Petrological Society of Korea 1993, 2:139-155.
81. Park J., Park K.H., Cheong C.S. Sr-Nd-Pb isotopic compositions of lavas from Cheju Island, Korea. Journal of Petrological Society of Korea 1996, 5:89-107.
82. Passchier C., Trouw R. Micro-Tectonics 1996, Springer-Verlag, Berlin.
83. Prior D.J., Boyle A.P., Brenker F., Cheadle M.C., Day A., Lopez G., Peruzzo L., Potts G.J., Reddy S., Spiess R., Timms N.E., Trimby P., Wheeler J., Zetterstrom L. The application of electron backscatter diffraction and orientation contrast imaging in the SEM to textural problems in rocks. American Mineralogist 1999, 84:1741-1759.
84. Rampone E., Bottazzi P., Ottolini L. Complementary Ti and Zr anomalies in orthopyroxene and clinopyroxene from mantle peridotites. Nature 1991, 354:518-520.
85. Roden M.F., Shimizu N. Ion microprobe analyses bearing on the composition of the upper mantle beneath the Basin and Range and Colorado plateau provinces. Journal of Geophysical Research-Solid Earth 1993, 98:14091-14108.
86. Sager W.W., Handschumacher D.W., Hilde T.W.C., Bracey D.R. Tectonic evolution of the northern Pacific plate and Pacific-Farallon-Izanagi triple junction in the late Jurassic and early Cretaceous. Tectonophysics 1988, 155:345-364.
87. Salah M.K., Seno T., Iidaka T. Upper mantle anisotropy beneath central and southwest Japan: an insight into subduction-induced mantle flow. Journal of Geodynamics 2008, 46:21-37.
88. Salah M.K., Seno T., Iidaka T. Seismic anisotropy in the wedge above the Philippine Sea slab beneath Kanto and southwest Japan derived from shear wave splitting. Journal of Asian Earth Sciences 2009, 34:61-75.
89. Savage M.K. Seismic anisotropy and mantle deformation: what have we learned from shear wave splitting?. Reviews of Geophysics 1999, 37:65-106.
90. Sibuet J.C., Letouzey J., Barbier F., Charvet J., Foucher J.P., Hilde T.W.C., Kimura M., Chiao L.Y., Marsset B., Muller C., Stephan J.F. Back arc extension in the Okinawa Trough. Journal of Geophysical Research-Solid Earth and Planets 1987, 92. 14041+.
91. Steinberger B., Gaina C. Plate-tectonic reconstructions predict part of the Hawaiian hotspot track to be preserved in the Bering Sea. Geology 2007, 35:407-410.
92. Streckeisen A. To each plutonic rock its proper name. Earth-Science Reviews 1976, 12:1-33.
93. Szabó C., Falus G., Zajacz Z., Kovács I., Bali E. Composition and evolution of lithosphere beneath the Carpathian-Pannonian Region: a review. Tectonophysics 2004, 393:119-137.
94. Szabó C., Harangi S., Vaselli O., Downes H. Temperature and oxygen fugacity in peridotite xenoliths from the Carpathian-Pannonian Region. Acta Vulcanologica 1995, 7:231-239.
95. Tatsumi Y., Shukuno H., Yoshikawa M., Chang Q., Sato K., Lee M.W. The petrology and geochemistry of volcanic rocks on Jeju Island: plume magmatism along the Asian continental margin. Journal of Petrology 2005, 46:523-553.
96. Tommasi A., Mainprice D., Canova G., Chastel Y. Viscoplastic self-consistent and equilibrium-based modeling of olivine lattice preferred orientations: implications for the upper mantle seismic anisotropy. Journal of Geophysical Research-Solid Earth 2000, 105:7893-7908.
97. Tommasi A., Tikoff B., Vauchez A. Upper mantle tectonics: three-dimensional deformation, olivine crystallographic fabrics and seismic properties. Earth and Planetary Science Letters 1999, 168:173-186.
98. Tommasi A., Vauchez A., Fernandes L.A.D., Porcher C.C. Magma assisted strain localization in an orogen-parallel transcurrent shear zone of southern Brazil. Tectonics 1994, 13:421-437.
99. Tommasi A., Vauchez A., Ionov D.A. Deformation, static recrystallization, and reactive melt transport in shallow subcontinental mantle xenoliths (Tok Cenozoic volcanic field, SE Siberia). Earth and Planetary Science Letters 2008, 272:65-77.
100. Toramaru A., Fujii N. Connectivity of melt phase in a partially molten peridotite. Journal of Geophysical Research-Solid Earth and Planets 1986, 91:9239-9252.
101. Van Der Wal D., Bodinier J.L. Origin of the recrystallisation front in the Ronda peridotite by km-scale pervasive porous melt flow. Contributions to Mineralogy and Petrology 1996, 122:387-405.
102. Vauchez A., Garrido C.J. Seismic properties of an asthenospherized lithospheric mantle: constraints from lattice preferred orientations in peridotite from the Ronda massif. Earth and Planetary Science Letters 2001, 192:235-249.
103. Vauchez A., Tommasi A. Plume-lithosphere interaction: effects on the seismic anisotropy of the lithospheric mantle. Geophysical Research and Abstract 2003, 5:11450.
104. Vissers R.L.M., Drury M.R., Newman J., Fliervoet T.F. Mylonitic deformation in upper mantle peridotites of the North Pyrenean Zone (France): implications for strength and strain localization in the lithosphere. Tectonophysics 1997, 279:303-325.
105. Waff H.S., Faul U.H. Effects of crystalline anisotropy on fluid distribution in ultramafic partial melts. Journal of Geophysical Research 1992, 97:9003-9014.
106. Walter M.J., Sisson T.W., Presnall D.C. A mass proportion method for calculating melting reactions and application to melting of model upper-mantle lherzolite. Earth and Planetary Science Letters 1995, 135:77-90.
107. Warren J.M., Hirth G. Grain size sensitive deformation mechanisms in naturally deformed peridotites. Earth and Planetary Science Letters 2006, 248:438-450.
108. Wirth E., Long M.D. Frequency dependent shear wave splitting beneath Japan and implications for the mantle wedge. EOS Transaction AGU Fall Meet Suppl 2008, 89:V31A-2115.
109. Witt-Eickschen G., Seck H.A. Solubility of Ca and Al in orthopyroxene from spinel peridotite - an improved version of an empirical geothermometer. Contributions to Mineralogy and Petrology 1991, 106:431-439.
110. Won C., Kil Y.W., Lee M.W. The petrology of volcanic rocks on the northeastern slope Cheju Island. Journal of Korean Earth Science Society 1998, 19:329-342.
111. Yanai S., Park B., Otoh S. The Honam shear zone (South Korea): deformation and tectonic implication in the Far East. Scientific Papers of College of Arts and Science, University of Tokyo 1985, 35:181-210.
112. Yun S., Koh J., Anh J. A study on the spinel-lherzolite xenolith in the alkali basalt from Eastern Cheju Island, Korea. Economics of Environmental Geology 1998, 31:447-458.
113. Yun S., Koh J., Park J. Petrology of the Taeheung-ri Lava in southeastern Jeju Island. Journal of Petrological Society of Korea 2002, 11:17-29.
114. Zanetti A., Mazzucchelli M., Rivalenti G., Vannucci R. The Finero phlogopite-peridotite massif: an example of subduction-related metasomatism. Contributions to Mineralogy and Petrology 1999, 134:107-122.
115. Zhang S., Karato S.-I., Fitz Gerald J., Faul U.H., Zhou Y. Simple shear deformation of olivine aggregates. Tectonophysics 2000, 316:133-152.
116. Zhang S.Q., Karato S. Lattice preferred orientation of olivine aggregates deformed in simple shear. Nature 1995, 375:774-777.