Noncoaxial K-feldspar and AMS subfabrics in the Land's End granite, Cornwall: Evidence of magmatic fabric decoupling during late deformation and matrix crystallization

Journal of Geophysical Research: Solid Earth

Volumn 115, Issue 9, 2010, Pages

  Kratinová, Zuzana ^a,b   Ježek, Josef ^c   Schulmann, Karel ^d,e   Hrouda, František ^c,f   Shail, Robin K ^g   Lexa, Ondrej ^c  

^a INSTITUTE OF MATHEMATICS   (Czech Republic)

^b UNIVERSITY OF LISBON   (Portugal)

^c CHARLES UNIVERSITY   (Czech Republic)

^d UNIVERSITÉ DE STRASBOURG EOST   (France)

^e UNIVERSITÉ DE STRASBOURG   (France)

^f Advanced Geoscience Instruments Company   (Czech Republic)

^g UNIVERSITY OF EXETER   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

CRYSTALLIZATION; DEFORMATION; EMPLACEMENT; FELDSPAR; GRAIN SIZE; GRANITE; MAGMA; MAGNETIC ANISOTROPY; MICROSTRUCTURE; NUMERICAL MODEL; PHENOCRYST; PLUTON; QUANTITATIVE ANALYSIS;

CORNWALL [ENGLAND]; ENGLAND; UNITED KINGDOM;

EID: 77957549516     PISSN: 21699313     EISSN: 21699356     Source Type: Journal    
DOI: 10.1029/2009JB006714     Document Type: Article

References (95)

1. Alexander, A. C., and R. K. Shail (1995), Late Variscan structures on the coast between Perranporth and St. Ives, south Cornwall, Proceedings of the Ussher Society, 8, 398-404.
2. Alexander, A. C., and R. K. Shail (1996), Late- to post-Variscan structures on the coast between Penzance and Pentewan, south Cornwall, Proceedings of the Ussher Society, 9, 72-78.
3. Arthaud, F., and P. Matte (1977), Late-Palaeozoic strike-slip faulting in southern Europe and northern Africa: Result of a right lateral shear zone between the Appalachians and the Urals, Bull. Geol. Soc. Am., 88, 1305-1320.
4. Auréjac, J. B., G. Gleizes, H. Diot, and J. L. Bouchez (2004), The Quérigut Complex (Pyrennes, France) revised by the AMS technique: A syntec-tonic pluton of the Variscan dextral transpression, Bull. Soc. Geol. Fr., 175, 157-174.
5. Aydin, A., E. C. Ferré, and Z. Aslan (2007), The magnetic susceptibility of granitic rocks as a proxy for geochemical differentiation: Example from the Saruhan granitoids, NE Turkey, Tectonophysics, 44, 85-95.
6. Benn, K., 1994. Overprinting of magnetic fabrics in granites by small strains: Numerical modeling, Tectonophysics, 233, 153-162.
7. Booth, B. (1968), Petrogenetic significance of alkali feldspar megacrysts and their inclusions in Cornubian granites, Nature, 217, 1036-1038, doi:10.1038/2171036a0.
8. Booth, B., and C. S. Exley (1987), Petrological features of the Land's End granites, Proceedings of the Ussher Society, 6, 439-446.
9. Bouchez, J. L. (1997), Granite is never isotropic: An introduction to AMS studies of granitic rocks, in Granite: from segregation of melt to emplacement fabrics, edited by J. L. Bouchez, pp. 95-112, Kluwer Academic Publishers, Dordrecht.
10. Bouchez, J. L. (2000), Anistropie de susceptibilité magnétique et fabrique des granites, C. R. Acad. Sci., 330, 1-14.
11. Bouchez, J. L., T. Mintsa Mi Nguema, L. Esteban, R. Siqueira, and R. Scrivener (2006), The tourmaline-bearing granite pluton of Bodmin (Cornwall, UK): Magnetic fabric study and regional inference, J. Geol. Soc. London, 163, 607-616.
12. Borradaile, G. J., and D. Gauthier (2003), Emplacement of an Archean gneiss dome, northern Ontario, Canada: Inflation inferred from magnetic fabrics, Tectonics, 22(2), 1011, doi:10.1029/2002TC001443.
13. Borradaile, G. J., and B. Henry (1997), Tectonic applications of magnetic susceptibility and its anisotropy. Earth-Sci Rev, 42, 49-93.
14. Borradaile, G. J., and M. Jackson (2004), Anisotropy of magnetic susceptibility (AMS): Magnetic petrofabrics of deformed rocks, In Magnetic Fabric: Methods and Applications, edited by F. Martin-Hernandez et al., Geological Society London, Special Publication, vol. 238, pp. 299-360.
15. Borradaile, G. J., and M. M. Kehlenbeck (1996), Possible Crypto tectonic magnetic fabrics in "Posttectonic" granitoid plutons of the Canadian Shield, Earth and Planetary Science Letters, 137, 119-127.
16. Chadima, M., and V. Jelínek (2008), Anisoft 4.2. - Anisotropy data browser, 11th Castle Meeting, Bojnice, Slovakia, 22-28 June.
17. Chappell, B. J., and R. Hine (2006), The Cornubian Batholith: An example of magmatic fractionation on a crustal scale, Resour. Geol, 56, 203-244.
18. Chen, Y., A. H. Clark, E. Farrar, H. A. H. P. Wasteneys, M. J. Hodgson, and A. V. Bromley (1993), Diachronous and independent histories of plu-tonism and mineralization in the Cornubian Batholith, southwest England, J. Geol. Soc. London, 150, 1183-1191.
19. Chesley, J. T., A. N. Halliday, L. W. Snee, K. Mezger, T. J. Shepherd, and R. C. Scrivener (1993), Thermochronology of the Cornubian batholith in southwest England: Implications for pluton emplacement and protracted hydrothermal mineralization, Geochim. Cosmochim. Ac, 57, 1817-1835.
20. Clark, A.H., Y. Chen, E. Farrar, and B. Northcote (1994), Refinement of the time/space relationships of intrusion and hydrothermal activity in the Cornubian batholith, Abstracts Volume, Ussher Society Annual Meeting, Minehead, January 1994.
21. Dangerfield, J., and J. R. Hawkes (1978), Variscan granites of South-west England, Proceedings of the Ussher Society, 4(2), 158-171.
22. Dearman, W. R. (1971), A general view of the structure of Cornubia, Proceedings of the Ussher Society, 2, 220-236.
23. Fisher, N. I., T. Lewis, and B. J. J. Embleton (1993), Statistical analysis of spherical data, 343 pp., Cambridge University Press, Cambridge, UK.
24. Flood, R. H., and R. H. Vernon (1988), Microstructural evidence of orders of crystallization in granitoid rocks, Lithos, 21, 237-245.
25. Ghosh, P. K. (1934), The Carnmenellis granite: its petrology metamor-phism and tectonics, J. Geol. Soc. London, 241-276.
26. Gleizes, G., G. Drevon, A. Asrat, and P. Barbey (2006), Structure, age and mode of emplacement of the Hercynian Borderes-Louron pluton (Central Pyrenees, France), Int. J. Earth. Sci., 95(6), 1039-1052.
27. Goode, A. J. J., and R. T. Taylor (1988), Geology of the country around Penzance, in Memoir of the British Geological Survey, Sheets 351 and 358 (England and Wales), 51 pp., HMSO, London.
28. Hawkes, J. R. (1981), A tectonic 'watershed' of fundamental consequence in the post-Westphalian evolution of Cornubia, Proceedings of the Ussher Society, 5, 128-131.
29. Henry, B. (1997), The magnetic zone axis: a new element of magnetic fabric for the interpretation of the magnetic lineation, Tectonophysics, 271, 325-329.
30. Higgins, M. D (1999), Origin of megacrysts in granitoids by textural coarsening: A crystal size distribution (CSD) study of microcline in the Cathedral Peak Granodiorite, Sierra Nevada, California, In Understanding granites: integrating new and classical techniques, edited by A. Castro et al., pp. 207-219, Geological Society of London Special Publication, vol. 168.
31. Housen, B. A., C. Richter, and B. A. van der Pluijm (1993), Composite magnetic anisotropy fabrics: Experiments, numerical models, and implications for the quantification of rock fabrics, Tectonophysics, 220, 1-12.
32. Hrouda, F. (1993), Theoretical models of magnetic anisotropy to strain relationship revisited, Phys. Earth Planet. Inter., 77, 237-249.
33. Hrouda, F. (1994), A technique for the measurement of thermal-changes of magnetic-susceptibility of weakly magnetic rocks by the Cs-2 apparatus and Kly-2 kappabridge, Geophys. J. Int., 118(3), 604-612.
34. Hrouda, F. (2002), Low-field variation of magnetic susceptibility and its effect on the anisotropy of magnetic susceptibility of rocks, Geophys. J. Int., 150, 715-723.
35. Hrouda, F. (2010), Modelling relationship between bulk susceptibility and AMS in rocks consisting of two magnetic fractions represented by ferromagnetic and paramagnetic minerals - Implications for understanding magnetic fabrics in deformed rocks, Journal of the Geological Society of India, 75(1), 254-266.
36. Hrouda, F., and J. Ježek (1999), Theoretical models for the relationship between magnetic anisotropy and strain: Effect of triaxial magnetic grains, Tectonophysics, 301, 183-190.
37. Hrouda, F., and K. Schulmann (1990), Conversion of the magnetic-susceptibility tensor into the orientation tensor in some rocks, Phys. Earth Planet. Inter., 63(1-2), 71-77.
38. Hrouda, F., V. Jelínek, and L. Hrušková (1990), A package of programs for statistical evaluation of magnetic data using IBM-PC computers, EOS Trans., AGU, San Francisco, pp.1289.
39. Hughes, S. P., R. J. Stickland, R. K. Shail, N. G. LeBoutillier, A. C. Alexander, and M. Thomas, (2009), The chronology and kinematics of late Palaeozoic deformation in the NW contact metamorphic aureole of the Land's End granite, Geoscience in South - West England, 12, 140-152.
40. Ildefonse, B., D. Sokoutis, and N. S., Mancktelow (1992), Mechanical Interactions between Rigid Particles in a Deforming Ductile Matrix - Analog Experiments in Simple Shear-Flow, J. Struct. Geol, 14(10), 1253-1266.
41. Jeffrey, G. B. (1922), The motion of ellipsoidal particles immersed in a viscous fluid, Proc. R. Soc. London, 102, 161-179.
42. Jelínek, V. (1978), Statistical processing of anisotropy of magnetic susceptibility measured on groups of specimens, Studia geophysica et geodetica, 22, 50-62.
43. Jelínek, V. (1981), Characterization of the magnetic fabric of rocks, Tectonophysics, 79, T63-T67.
44. Jelínek, V., and J. Pokorný (1997), Some new concepts in technology of transformer bridges for measuring susceptibility anisotropy of rocks, Phys. Earth Planet. Inter., 22, 179-181.
45. Jelínek, V., F. Hrouda, and D. H. Tarling (1994), New parameters for characterization of linear and planar elements using orientation tensor, in Textures of geological materials, edited by H. J. Bunge et al., pp. 393-399, DGM Verlag, Oberusel.
46. Ježek, J. (1994), Software for modeling the motion of rigid triaxial ellipsoidal particles in viscous flow, Computers and Geosciences, 20(3), 409-424.
47. Ježek, J., and F. Hrouda (2000), The relationship between the Lisle orientation tensor and the susceptibility tensor, Phys. Chem. Earth., 25(5), 469-474.
48. Ježek, J., and F. Hrouda (2002), Software for modeling the magnetic anisotropy of strained rocks, Computers and Geosciences, 28, 1061-1068.
49. Ježek, J., R. Melka, K. Schulmann, and Z. Venera (1994), The behaviour of rigid triaxial particles in viscous flows-modeling of fabric evolution in a multiparticle system, Tectonophysics, 229, 165-180.
50. Ježek, J., K. Schulmann, and K. Segeth, (1996), Fabric evolution of rigid inclusions during mixed coaxial and simple shear flows, Tectonophysics, 257, 203-221.
51. Johannes, W., and F. Holtz (1996), Petrogenesis and Experimental Petrology of Granitic Rocks, 335 pp., Springer-Verlag, Berlin Heidelberg.
52. Johnson, B. R., A. F. Glazner, and D. S. Coleman (2006), Potassium feldspar megacrysts in granites: Passive markers of magma dynamics or products of textural coarsening?, EOS Transaction of the American Geophysical Union, 87(52), V51B-1670.
53. Kratinová, Z., K. Schulmann, F. Hrouda, and R. K. Shail (2003), The role of regional tectonics and magma flow coupling versus magmatic processes in generating contrasting magmatic fabrics within the Land's End granite, Cornwall, Geoscience in south - west England, 10, 442-448.
54. Kratinová, Z., K. Schulmann, J. B. Edel, J. Ježek, and U. Schaltegger (2007), Model of successive granite sheet emplacement in transtensional setting: Integrated microstructural and anisotropy of magnetic susceptibility study, Tectonics, 26, TC6003, doi:10.1029/2006TC002035.
55. Launeau, P., and A. R. Cruden (1998), Magmatic fabric acquisition mechanisms in syenite: Results of combined anisotropy of magnetic susceptibility and image analysis study, J. Geophys. Res., 103(B3), 5067-5089, doi:10.1029/97JB02670.
56. Launeau, P., and P.-Y. F. Robin (1996), Fabric analysis using the intercept method, Tectonophysics, 267, 91-211.
57. Leveridge, B. E., M. T. Holder, and A. J. J. Goode (1990), Geology of the country around Falmouth, Memoir for 1:50000 geological sheet 352 (England and Wales), British Geological Survey. HMSO, London.
58. Lexa, O. (2003), Numerical approaches in structural and microstructural analyses, PhD Thesis, Charles University, Prague.
59. Lexa, O., P. Štípská, and K. Schulmann (2005), Contrasting textural record of two distinct metamorphic events of similar P-T conditions and different durations, J. Metamorph. Geol, 23(8), 649-666.
60. March, A. (1932), Mathematische Theorie der Regelung nach der Kornges-talt bei Affiner Deformation, Z. Kristallogr., 81, 285-298.
61. Martín-Hernández, F., and A. M. Hirt (2003), The anisotropy of magnetic susceptibility in biotite, muscovite and chlorite single crystals, Tectonophysics, 367(1-2), 13-28.
62. Miller, R. B., and S. R. Paterson (1999), In defense of magmatic diapirs, J. Struct. Geol, 21, 1161-1173.
63. Miller, R. B., and S. R. Paterson (2001), Construction of mid-crustal sheeted plutons: Examples from the North Cascades, Washington, Geol. Soc. Am. Bull, 113(11), 1423-1442.
64. Mintsa Mi Nguema, T., R. I. F. Trindade, J. L. Bouchez, and P. Launeau (2002), Selective thermal enhancement of magnetic fabrics from the Carnmenellis granite (British Cornwall), Phys. Chem. Earth, 27,1281-1287.
65. Müller, A., R. Seltmann, C. Halls, W. Siebel, P. Dulski, T. Jeffries, J. Spratt, and A. Kronz (2006), The magmatic evolution of the Land's End pluton, Cornwall, and associated pre-enrichment of metals, Ore Geol. Rev., 28(3), 329-367.
66. Parma, J., and K. Zapletal(1991), CS-1 apparatus for measuring the temperature dependence of low-field susceptibility of minerals and rocks (in cooperation with KLT-2 Kappabridge), Geofyzika Brno, Unpublished Report.
67. Paterson, S. R., and R. B. Miller (1998), Stoped blocks in plutons: Paleo-plumb bobs, viscometers, or chronometers?, J. Struct. Geol, 20(9/10), 1261-1272.
68. Paterson, S. R., R. H. Vernon, and O. T. Tobisch (1989), A review of criteria for identification of magmatic and tectonic foliations in granitoids, J. Struct. Geol, 11(3), 349-363.
69. Paterson, S. R., K. Fowler Jr., K. Schmidt, A. Yoshinobu, and S. Yuan (1998), Interpreting magmatic fabric patterns in plutons, Lithos, 44,53-82.
70. Rathore, J. S. (1980), A study of secondary fabrics in rocks from the lizard peninsula and adjacent areas in southwest cornwall, England, Tectonophysics, 68, 147-160.
71. Rattey, P. R., and D. J. Sanderson (1984), The structure of SW Cornwall and its bearing on the emplacement of the Lizard Complex, J. Geol. Soc. London, 141, 87-95.
72. Salmon, S. (1994), Mingling between coexisting granite magmas within the Land's End granite - preliminary observations, Proceedings of the Ussher Society, 8, 219-223.
73. Scheidegger, A. E. (1965), On the statistics of the orientation of bedding planes, grain axes, and similar sedimentological data, U.S. Geological Survey Professional Paper, 525-C, 164-167.
74. Schulmann, K., J-B. Edel, P. Hasalová, J. W. Cosgrove, J. Ježek, and O. Lexa, (2009), Influence of melt induced mechanical anisotropy on AMS fabrics and rheology of deforming migmatites, Central Vosges, France, J. Struct. Geol, doi:10.1016/j.jsg.2009.07.004,31(10),1223-1237.
75. Schulmann, K., J. Ježek, and Z. Venera (1997), Perpendicular linear fabrics in granite. Markers of combined simple shear and pure shear flow?, in From segregation of melt to emplacement fabrics, edited by J. L. Bouchez et al., pp.159-176, Kluwer Academic Publishers, Dordrecht.
76. Shail, R. K., and A. C. Alexander (1997), Late Carboniferous to Triassic reactivation of Variscan basement in the western English Channel: Evidence from onshore exposures in south Cornwall, J. Geol. Soc. London, 154, 163-168.
77. Shail, R. K., and B. E. Leveridge (2009), The Rhenohercynian passive margin of SW England: Development, inversion and extensional reactivation, CRACAD SCI II A, 341, 140-155.
78. Shail, R. K., and J. J. Wilkinson, (1994), Late- to post-Variscan extensional tectonics in south Cornwall, Proceedings of the Ussher Society, 66, 263-272.
79. Stimac, J. A., A. H. Clark, Y. Chen, and S. Garcia (1995), Enclaves and their bearing on the origin of the Cornubian batholith, southwest England, Mineral Mag, 59, 273-296.
80. Stone, M., and W. G. C. Austin (1961), The Metasomatic origin of the Potash feldspar MegaCrysts in the granites of southwest England, J Geol, 69(4), 464-472.
81. Tarling, D. H., and F. Hrouda (1993), The Magnetic Anisotropy of Rocks, 232 pp., Chapman and Hall, London.
82. Taylor, G. K. (2007), Pluton shapes in the Cornubian batholith: New perspectives from gravity modelling, J. Geol. Soc. London, 164, 525-528.
83. Tullis, J., and R. A. Yund (1977), Experimental deformation of dry westerly granite, J. Geophys. Res., 82(36), 5705-5718, doi:10.1029/ JB082i036p05705.
84. Venera, Z., K. Schulmann, R. Melka, and J. Ježek (1996), Fabric of por-phyric magmatites inferred from the preferred orientation of feldspar phe-nocrysts, Journal of Czech Geological Society, 41(3-4), 183-190.
85. Vernon, R. H. (1986), K-feldspar megacrysts in granites - Phenocrysts, not porphyroblasts, Earth-Science Reviews, 23, 1-63.
86. Vernon, R. H., and S. R. Paterson (2008), How late are K-feldspar megacrysts in granites?, Lithos, 104, 327-336.
87. Vigneresse, J. L., and B. Tikoff (1999), Strain partitioning during partial melting and crystallizing felsic magmas, Tectonophysics, 312, 117-132.
88. Vollmer, F. W. (1990), An application of eigenvalue methods to structural domain analysis, Geol. Soc. Am. Bull, 102, 786-791.
89. Warr, L. N., T. J. Primmer, and D. Robinson (1991), Variscan very low-grade metamoirphism in southwest England: A distathermal and thrust-related origin, J. Metamorph. Geol, 9, 751-764.
90. Willis, D. G. (1977), A kinematic model of preferred orientation, Geol. Soc. Am. Bull, 88, 883-894.
91. Žák, J., K. Schulmann, and F. Hrouda (2005), Multiple magmatic fabrics in the Sázava pluton (Bohemian Massif, Czech Republic): A result of superposition of wrench-dominated regional transpression on final emplacement, J. Struct. Geol, 27(5), 805-822.
92. Žák, J., S. R. Paterson, and V. Memeti (2007), Four magmatic fabrics in the Tuolumne batholith, central Sierra Nevada, California (USA): Implications for interpreting fabrics patterns in plutons and evolution of magma chambers in the upper crust, Geol. Soc. Am. Bull, 119, 184-201.
93. Žák, J., K. Verner, and P. Týcová (2008), Multiple magmatic fabrics in plutons: An overlooked tool for exploring interactions between magmatic processes and regional deformation?, Geol. Mag., 145, 537-551, doi: 10.1007/S0016756808004573.
94. Zapletal, K. (1990), Low-field susceptibility anisotropy of some biotite crystals, Phys. Earth Planet. Inter, 63, 85-97.
95. Ziegler, P. A., and P. Dèzes (2006), Crustal evolution of western and central Europe, in European lithosphere dynamics, edited by D.G. Gee and A.A. Stephenson, pp. 43-56, Geological Society of London Memoirs 32.