Clasts of Variscan high-grade rocks within Upper Viséan conglomerates - Constraints on exhumation history from petrology and U-Pb chronology

Journal of Metamorphic Geology

Volumn 25, Issue 7, 2007, Pages 781-801

  Kotkova J ^a   Gerdes, A ^b,c   Parrish, R R ^b   Novak M ^a  

^a MASARYK UNIVERSITY   (Czech Republic)

^b NATURAL ENVIRONMENT RESEARCH COUNCIL   (United Kingdom)

^c GOETHE UNIVERSITY   (Germany)

Author keywords

Bohemian Massif; Conglomerate; Granulite; Monazite; U Pbdating; Variscan flysh; Zircon

Indexed keywords

CLAST; CONGLOMERATE; CRYSTALLINE ROCK; DENUDATION; EXHUMATION; GEOTHERMOMETRY; GRANULITE FACIES; HERCYNIAN OROGENY; MONAZITE; P-T CONDITIONS; PETROLOGY; TEXTURE; URANIUM-LEAD DATING; ZIRCON;

BOHEMIAN MASSIF; CENTRAL EUROPE; EURASIA; EUROPE;

EID: 34548300025     PISSN: 02634929     EISSN: 15251314     Source Type: Journal    
DOI: 10.1111/j.1525-1314.2007.00730.x     Document Type: Article

References (104)

1. Aftalion, M., Bowes, D. R. & Vrána, S., 1989. Early Carboniferous U-Pb zircon age for garnetiferous perpotassic granulites, Blanský les massif, Czechoslovakia. Neues Jahrbuch für Mineralogie-Monatshefte, 4, 145-152.
2. Bábek, O., Mikuláš, R., Zapletal, J. & Lhotský, T., 2004. Combined tectonic-sediment supply-driven cycles in a Lower Carboniferous deep-marine foreland basin, Moravice Formation, Czech Republic. International Journal of Earth Science, 93, 241-261.
3. Bábek, O., Tomek, C., Melichar, R., Kalvoda, J. & Otava, J., 2006. Structure of unmetamorphosed Variscan tectonic units of the souther Moravo-Silesian zone, Bohemian Massif: A review. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen, 239, 37-75.
4. Barbey, P., Marignac, C., Montel, J. M., Macaudiere, J., Gasquet, D. & Jabbori, J., 1999. Cordierite growth textures and the conditions of genesis and emplacement of crustal granitic magmas: The Velay granite complex (Massif Central, France). Journal of Petrology, 40, 1425-1441.
5. Berman, R. G., 1991. Thermobarometry using multi-equilibrium calculations: A new technique, with petrological applications. Canadian Mineralogist, 29, 833-855.
6. 2. Contributions to Mineralogy and Petrology, 126, 1-24.
7. Bingen, B. & van Breemen, O., 1998. U-Pb monazite ages in amphibolite- to granulite-facies orthogneiss reflect hydrous mineral breakdown reactions: Sveconorwegian Province of SW Norway. Contributions to Mineralogy and Petrology, 132, 336-353.
8. Bohlen, S. R., Wall, V. J. & Boettcher, A. L., 1983. Geobarometry in granulites. In: Kinetics and Equilibrium in Mineral Reaction (ed. Saxena, S.K.), pp. 141-171. Springer-Verlag, New York.
9. van Breemen, O., Aftalion, M., Bowes, D. R. et al., 1982. Geochronological studies of the Bohemian Massif, Czechoslovakia, and their significance in the evolution of central Europe. Transactions of the Royal Society of Edinburgh, Earth Science Series, 73, 89-108.
10. Buriánek, D. & Novák, M., 2002. Contribution to the knowledge of provenance of pebbles from the Upper Viséan conglomerates in the Drahany Hights: III. Orbicular tourmaline-bearing granite (in Czech with English summary). Acta Musei Moraviae, Scientiae Geologicae, 87, 145-152.
11. Carswell, D.A. & O'Brien, P.J., 1993. Thermobarometry and geotectonic significance of high-pressure granulites: Examples from the Moldanubian Zone of the Bohemian Massif in Lower Austria. Journal of Petrology, 34, 427-459.
12. Čopjaková, R. & Novák, M., 2003. Contribution to knowledge of provenance of pebbles from the Upper Viséan conglomerates in the Drahany Uplands: IV. Garnet-bearing micaschist with tourmaline (in Czech with English summary). Acta Musei Moraviae, Scientiae Geologicae, 88, 167-175.
13. Čopjaková, R. & Novák, M., 2005. Provenance changes as reflected in the psephitic and psammitic fraction of the Myslejovice Formation sediments (in Czech). Abstract. Moravsko-slezsképaleozoikum, sborník abstrakt̊, Olomouc, 7-8.
14. Čopjaková, R., Sulovský, P. & Otava, J., 2001. Use of detrital garnet geochemistry for determination of provenance and lithostratigraphy of the Drahany Upland Kulm. Mineralia Slovaca, 33, 509-511.
15. Čopjaková, R., Sulovský, P. & Peterson, B., 2005. Major and trace elements in pyrope-almandine garnets as sediment provenance indicators of the Lower Carboniferous Culm sediments, Drahany Uplands, Bohemian Massif. Lithos, 82, 51-70.
16. Corfu, F., Hanchar, J. M., Hoskin, P. W. O. & Kinny, P., 2003. Atlas of zircon textures. In: Zircon (eds Hanchar, J. M. & Hoskin, P. W. O.), Reviews in Mineralogy & Geochemistry, 53, 468-500.
17. 39Ar mineral age controls. Tectonophysics, 210, 135-153.
18. Dallmeyer, R. D., Franke, W. & Weber, K., 1995. Pre-Permian Geology of Central and Eastern Europe. VIII Moravo-Silesian Zone. Springer-Verlag, Berlin, Heidelberg, New York, pp. 469-490.
19. Ding, L., Zhong, D. L., Yin, A., Kapp, P. & Harrison, T. M., 2001. Cenozoic structural and metamorphic evolution of the eastern Himalayan syntaxis (Namche Barwa). Earth and Planetary Science Letters, 192, 423-438.
20. Franke, W., 1995. Rhenohercynian foldbelt; autochthon and non-metamorphic nappe units: Stratigraphy. In: Pre-Permian Geology of Central and Eastern Europe (eds Dallmeyer, R. D., Franke, W. & Weber, K.), pp. 33-49. Springer-Verlag, Berlin, Heidelberg, New York.
21. Friedl, G., 1997. U/Pb Datierungen an Zirkonen und Monaziten aus Gesteinen vom Österrechischen Anteil der Böhmischen Masse. Doktoral Thesis. Paris-Lodron Universität, Salzburg, Austria.
22. Friedl, G., Cooke, R. A., Finger, F., McNaughton, N. J. & Fletcher, I. R., 2003. U-Pb SHRIMP dating and trace element investigations on multiple zoned zircons from a South-Bohemian granulite. Journal of the Czech Geological Society, 48, 51.
23. Fritz, H., Dallmeyer, R. D. & Neubauer, F., 1996. Thick-skinned versus thin-skinned thrusting: Rheology-controlled thrust propagation in the Variscan collisional belt (the southeastern Bohemian Massif, Czech Republic-Austria). Tectonics, 15, 1389-1413.
24. Fuhrman, M. L. & Lindsley, D. H., 1988. Ternary-feldspar modeling and thermometry. American Mineralogist, 73, 201-215.
25. Gerdes, A., 2001. Magma homogenisation during anatexis, ascent and/or emplacement? Constraints from the Variscan Weinsberg Granites. Terra Nova, 13/4, 305-312.
26. Gerdes, A., Wörner, G. & Henk, A., 2000. Post-collisional granite generation and HT-LP metamorphism by radiogenic heating: The example from the Varsican South Bohemian Batholith. Journal of the Geological Society London, 157, 577-587.
27. Gerdes, A., Friedl, G., Parrish, R. R., von Quadt, A. & Finger, F., 2002. U-Pb dating of South Bohemian granites: Constraints for the longevity of melting Cadomian crust. Pangeo Austria Abstracts, 56-57.
28. Gradstein, F. M. & Ogg, J., 1996. A Phanerozoic time scale. Episodes, 19, 3-5.
29. Green, D. H. & Lambert, I. B., 1965. Experimental crystallization of anhydrous granite at high pressures and temperatures. Journal of Geophysical Research, 70, 5259-5268.
30. Green, D. H. & Ringwood, A. E., 1967. An experimental investigation of gabbro to eclogite transformation and its petrological applications. Geochimica et Cosmochimica Acta, 31, 767-833.
31. Guan, H., Sun, M., Wilde, S. A., Zhou, X. H. & Zhai, M. G., 2002. SHRIMP U-Pb zircon geochronology of the Fuping Complex: Implications for formation and assembly of the North China Craton. Precambrian Research, 113, 1-18.
32. 2. Journal of Petrology, 25, 665-696.
33. Harley, S. L., 1984b. An experimental study of the partitioning of Fe and Mg between garnet and orthopyroxene. Contributions to Mineralogy and Petrology, 86, 359-373.
34. Hartley, A. J. & Otava, J., 2001. Sediment provenance and dispersal in a deep marine foreland basin: The Lower Carboniferous Culm Basin, Czech Republic. Journal of the Geological Society of London, 158, 137-150.
35. Havíř, J., 1999. The fabric of the Culm conglomerates in the eastern parts of the Nízký Jeseník and Drahany Uplands, eastern margin of the Bohemian Massif, the Czech Republic. Geologica Sudetica, 32, 1-11.
36. Hawkins, D. P. & Bowring, S. A., 1997. U-Pb systematics of monazite and xenotime: Case studies from the Paleoproterozoic of the Grand Canyon, Arizona. Contributions to Mineralogy and Petrology, 127, 87-103.
37. Holland, T. J. B., 1980. The reaction albite = jadeite + quartz determined experimentally in the range 600-1200 °C. American Mineralogist, 65, 129-134.
38. Holub, F. V., 1997. Ultrapotassic plutonic rocks of the durbachite series in the Bohemian Massif: Petrology, geochemistry and petrogenetic interpretation. Sborník Geologických Věd, Ložiskova Geologie Mineralogie, 31, 5-26.
39. Holub, F. V., Cocherie, A. & Rossi, P., 1997. Radiometric dating of granitic rocks from the Central Bohemian Plutonic Complex (Czech Republic): Constraints on the chronology of thermal and tectonic events along the Moldanubian-Barrandian boundary. Comptes Rendus de l'Academie des Sciences, Serie I Fascicule A- Sciences de la Terre et des Planetes, 325, 19-26.
40. Hoskin, P. W. O. & Black, L. P., 2000. Metamorphic zircon formation by solid-state recrystallization of protolith igneous zircon. Journal of Metamorphic Geology, 18, 423-439.
41. Houzar, S. & Novák, M., 2001. Contribution to knowledge of provenance of pebbles from the Upper Viséan conglomerates in the Drahany Uplands: I. Graphitic quartzite with vanadium-bearing muscovite (in Czech with English summary). Acta Musei Moraviae, Scientiae Geologicae, 86, 103-109.
42. Houzar, S. & Novák, M., 2002. Contribution to knowledge of provenance of pebbles from the Upper Viséan conglomerates in the Drahany Uplands: II. Calcitic marbles. (in Czech with English summary). Acta Musei Moraviae, Scientiae Geologicae, 87, 137-144.
43. Janoušek, V. & Gerdes, A., 2003. Timing the magmatic activity within the Central Bohemian Pluton, Czech Republic: Geochronology of the Sázava and Tábor intrusions and their geotectonic significance. Journal of the Czech Geological Society, 48, 70-71.
44. Janoušek, V., Gerdes, A., Vrana, S. et al., 2006. Low-pressure granulites of the Lišov Massif, Southern Bohemia: Viséan metamorphism of Late Devonian plutonic arc rocks. Journal of Petrology, 47, 705-745.
45. Jung, S. & Mezger, K., 2001. Geochronology in migmatites - A Sm-Nd, U-Pb and Rb-Sr study from the Proterozoic Damara belt (Namibia): implications for polyphase development of migmatites in high-grade terranes. Journal of Metamorphic Geology, 19, 77-97.
46. Klötzli, U. S. & Parrish, R. R., 1996. Zircon U/Pb and Pb/Pb geochronology of the Rastenberg granodiorite, South Bohemian Massif, Austria. Mineralogy and Petrology, 58, 197-214.
47. Kotková, J., 1998a. Garnet-bearing mafic granulites from the Lišov granulite massif. Geolines, 6, 37.
48. Kotková, J., 1998b. Pyroxene-garnet-bearing granulites from the Lišov granulite massif. MS, Czech Geological Survey, 24 p. (in Czech).
49. Kotková, J. & Harley, S. L., 1999. Formation and evolution of HP leucogranulites: Experimental constraints and unresolved issues. Physics and Chemistry of the Earth Part A-Solid Earth and Geodesy, 24, 299-304.
50. Kotková, J., Kröner, A., Todt, W. & Fiala, J., 1996. Lower Carboniferous high-pressure event in the Bohemian Massif: Evidence from North Bohemian granulites. Geologische Rundschau, 85, 154-161.
51. Kotková, J., Harley, S. L. & Fišera, M., 1997. A vestige of very high - pressure (ca. 28 kbar) metamorphism in the Variscan Bohemian Massif, Czech Republic. European Journal of Mineralogy, 9, 1017-1033.
52. Kotková, J., Novák, M., Leichmann, J. & Houzar, S., 2001. Nature and provenance of exotic rock types from Lower Carboniferous Conglomerates (Eastern Bohemian Massif). Geolines, 13, 81-82.
53. Kotková, J., Leichmann, J. & Novák, M., 2002. HT rocks from the Viséan conglomerates - further evidence for an external heat source in the internal zone of European Variscides. IMA Abstracts, Edinburgh.
54. Kotková, J., Schaltegger, U. & Leichmann, J., 2003. 338-335 Ma old intrusions in the E Bohemian Massif - a relic of the orogen-wide durbachitic magmatism in European Variscides. Journal of the Czech Geological Society, 48, 80-81.
55. Kretz, R., 1983. Symbols for rock-forming minerals. American Mineralogist, 68, 277-279.
56. Krogh, T. E., 1982. Improved accuracy of U-Pb ages by the creation of more concordant systems using an air abrasion technique. Geochimica et Cosmochimica Acta, 46, 637-649.
57. Kröner, A., O'Brien, P. J., Nemchin, A. A. & Pidgeon, R. T., 2000. Zircon ages for high pressure granulites from South Bohemia, Czech Republic, and their connection to Carboniferous high temperature processes. Contributions to Mineralogy and Petrology, 138, 127-142.
58. Kumpera, O., 1977. A review of the fauna of the Moravo-Silesian Kulm. In: Proceedings of the Symposium of Carboniferous Stratigraphy (eds Wagner, R. H. & Holub, V. H.), pp. 235-264. UUG, Praha.
59. Kumpera, O. & Lang, V., 1975. Goniatites of the Drahany Culm (Bohemian Massif, Moravo-Silesian Zone) (in Czech). Časopis slezského muzea, Ser A, 24, 11-34.
60. Ludwig, K. R., 1989. Pb.Dat: A computer program for processing raw Pb-U-Th isotope data. US Geological Survey Open File Report, 88, 557.
61. Ludwig, K. R., 2001. User's manual for Isoplot/Ex Version 2.49, A Geochronological Toolkit for Microsoft Excel. Berkley Geochronology Center, Special Publication 1a, Berkley, CA.
62. Matte, P., Maluski, H. & Echtler, H., 1985. Variscan eastward ductile shearing in the Waldviertel Nappes (South Eastern Bohemian Massif, Austria). Comptes Rendus des Sciences, Serie II, 301, 721-729.
63. Matte, P., Maluski, H., Rajlich, P. & Franke, W., 1990. Terrane boundaries in the Bohemian Massif: Result of large-scale Variscan shearing. Tectonophysics, 177, 151-170.
64. Medaris, L. G., Beard, B. L., Johnson, C. M. et al., 1995. Garnet pyroxenite and eclogite in the Bohemian Massif -geochemical evidence for Variscan recycling of subducted lithosphere. Geologische Rundschau, 84, 489-505.
65. Melichar, R., Kotková, J., 2003. Introduction to regional geology of the eastern margin of the Bohemian Massif. In: Geology without Frontiers: Magmatic and Metamorphic Evolution of Central European Variscides (ed. Kotková, J.), pp. 5-10. Excursion Guide, Czech Geological Society, Prague.
66. Menning, M., Weyer, D., Drozdzewski, G., van Ameron, H. W. J. & Wendt, I., 2000. A Carboniferous time scale 2000: Discussion and use of geological parameters as time indicators from Central and Western Europe. Geologische Jahrbuch, A156, 3-44.
67. Mezger, K. & Krogstad, E. J., 1997. Interpretation of discordant U-Pb zircon ages: An evaluation. Journal of Metamorphic Geology, 15, 127-140.
68. Mezger, K., Hanson, G.N. & Bohlen, S.R., 1989. High-precision U-Pb ages of metamorphic rutile - application to the cooling history of high-grade terranes. Earth and Planetary Science Letters, 96, 106-118.
69. Nehyba, S. & Mastalerz, K., 1995. Sedimentological contribution to the study of the Račice and Luleč conglomerates (in Czech). Geologickévýzkumy na Moravěa ve Slezsku v r. 1994, 66-68.
70. 5-quartz geobarometer. In: Thermodynamics of Minerals and Melts. (eds Newton, R. C., Navrotsky, A. & Wood, B. J.), pp. 131-147. Springer-Verlag, New York.
71. Newton, R. C. & Perkins, D., 1982. Thermodynamic calibration of geobarometers based on the assemblages garnet-plagioclase-orthopyroxene (clinopyroxene)-quartz. American Mineralogist, 67, 203-222.
72. Noble, S. R., Tucker, R. D. & Pharaoh, T. C., 1993. Lower Palaeozoic and Precambrian igneous rocks from eastern England, and their bearing on late Ordovician closure of the Tornquist Sea: Constraints from U-Pb and Nd isotopes. Geological Magazine, 130, 835-846.
73. Novák, M, 2001. Are granitic pegmatites a toy for descriptive mineralogists or a useful tool for geologists? MinPet2001 Symposium. Mitteilungen der Österreichischen Mineralogischen Gesellschaft, 146, 217-219.
74. O'Brien, P.J., 1997. Garnet zoning and reaction textures in overprinted eclogites, Bohemian Massif, European Variscides: A record of their thermal history during exhumation. Lithos, 41, 119-133.
75. O'Brien, P. J. & Rötzler, J., 2003. High-pressure granulites: formation, recovery of peak conditions and implications for tectonics. Journal of Metamorphic Geology, 21, 3-20.
76. O'Hara, M. J., Richardson, S. W. & Wilson, G., 1971. Garnet-peridotite stability and occurrence in crust and mantle. Contributions to Mineralogy and Petrology, 32, 48-68.
77. Otava, J. & Gilíková, H., 1999. Correlation of lithological markers within the Moravian-Silesian Culm. Geolines, 8, 53-55.
78. Parrish, R. R., 1987. An improved micro-capsule for zircon dissolution in U-Pb geochronology. Chemical Geology, 66, 99-102.
79. Pidgeon, R. T., 1992. Recrystallization of oscillatory zoned zircon - some geochronological and petrological implications. Contributions to Mineralogy and Petrology, 110, 463-472.
80. Pin, C. & Vielzeuf, D., 1983. Granulites and related rocks in Variscan Median Europe: A dualistic interpretation. Tectonophysics, 93, 47-74.
81. Roberts, M. P. & Finger, F., 1997. Do U-Pb zircon ages from granulites reflect peak metamorphic conditions? Geology, 25, 319-322.
82. Roddick, J. C., 1987. Generalized numerical error analyses with applications to geochronology and thermodynamics. Geochimica et Cosmochimica Acta, 51, 2129-2135.
83. Romer, R. L. & Rötzler, J., 2001. P-T-t evolution of ultrahigh-temperature granulites from the Saxon Granulite Massif, Germany. Part II: Geochronology. Journal of Petrology, 42, 2015-2032.
84. Rubatto, D., 2002. Zircon trace element geochemistry: Partitioning with garnet and the link between U-Pb ages and metamorphism. Chemical Geology, 184, 123-138.
85. Schneider, D., Handler, R., Neubauer, F., Kalvoda, J. & Tomek, Č., 1999. Ar-Ar single and multi-grain ages of detrital white mica from the Silesian Culm basin (Czech Republic). Geolines, 8, 59-60.
86. Schulmann, K., Melka, R., Lobkowicz, M., Ledru, P., Lardeaux, J.-M. & Autran, A., 1994. Contrasting styles of deformation during progressive nappe stacking at the southeastern margin of the Bohemain Massif (Thaya dome). Journal of Structural Geology, 16, 355-370.
87. Schulmann, K., Kröner, A., Hegner, E. et al., 2005. Chronological constraints on the pre-orogenic history of deep-seated rocks along the eastern margin of the Variscan orogen, Bohemian Massif, Czech Republic. American Journal of Sciences, 305, 407-448.
88. Špaček, P. & Kalvoda, J., 2000. Reconstruction of syn- and postsedimentary tectonic events in flysch basin from limestone pebbles variation: Drahany Kulm of the Moravian Rhenohercynian Zone Vol 51, pg 41, 2000. Geologica Carpathica, 51, 37-47.
89. Spear, F.S., 1993. Metamorphic phase equilibria and pressure-temperature-time paths. Mineralogical Society of America, Washington, D.C., MI, 779 p.
90. Spear, F. S. & Parrish, R. R., 1996. Petrology and cooling rates of the Valhalla complex, British Columbia, Canada. Journal of Petrology, 37, 733-765.
91. Stacey, J. S. & Kramers, J. D., 1975. Approximation of terrestrial lead isotope evolution by a two-stage model. Earth and Planetary Science Letters, 26, 207-221.
92. Štelcl, J., 1960. Petrography of Culm conglomerates of the souther part of the Drahany Upland (in Czech). Folia Universitatis Purkynianae Brunensis, Geologia, 1, 1-103.
93. Tollmann, A., 1982. Grossraumiger variszischer Deckenbau im Moldanubikum und neue Gedanken zum Variszikum Europas. Geotektonische Forschungen, 64, 1-91.
94. Urban, M., 1992. Kinematics of the Variscan thrusting in the Eastern Moldanubicum (Bohemian Massif, Czechoslovakia): Evidence from the Náměšt' granulite massif. Tectonophysics, 201, 371-391.
95. Vavra, G., Gebauer, D., Schmid, R. & Compston, W., 1996. Multiple zircon growth and recrystallization during polyphase Late Carboniferous to Triassic metamorphism in granulites of the Ivrea Zone (Southern Alps): An ion microprobe (SHRIMP) study. Contributions to Mineralogy and Petrology, 122, 337-358.
96. Vrána, S., 1989. Perpotassic granulites from southern Bohemia - a new rock type derived from partial melting of crustal rocks under upper mantle conditions. Contributions to Mineralogy and Petrology, 103, 510-522.
97. Vrána, S., 1992. The Moldanubian Zone in southern Bohemia: polyphase evolution of imbricated crustal and upper mantle segments. In: Proceedings of the 1st International Conference on the Bohemian Massif (ed. Kukal, Z.), 26 September to 3 October 1988, pp. 331-335. Prague, Czech Republic.
98. Vrána, S. & Frýda, J., 2003. Ultrahigh-pressure grossular-rich garnetite from the Moldanubian Zone, Czech Republic. European Journal of Mineralogy, 15, 43-54.
99. Vrána, S. & Novák, M., 2000. Petrology and geochemistry of granulite clasts in the Viséan Luleč conglomerate, Kulm in central Moravia, Czech Republic. Věstník Českého geologického ústavu, 75, 405-413.
100. Watson, E.B., Vicenzi, E.P. & Rapp, R.P., 1989. Inclusion Host Relations Involving Accessory Minerals in High- Grade Metamorphic and Anatectic Rocks. Contributions to Mineralogy and Petrology, 101, 220-231.
101. Wendt, J. I., Kröner, A., Fiala, J. & Todt, W., 1994. U-Pb zircon and Sm-Nd dating of Moldanubian HP/HT granulites from South Bohemia. Journal of the Geological Society of London, 151, 83-90.
102. York, D., 1969. Least squares fitting of a straight line with correlated errors. Earth and Planetary Science Letters, 5, 320-324.
103. Zachovalová, K. & Leichmann, J., 2004. Contribution to knowledge of provenance of pebbles from the Upper Viséan conglomerates in the Drahany Uplands: V. Durbachites (in sCzech with English summary). Acta Musei Moraviae, Scientiae Geologicae, 89, 161-171.
104. Zhu, X. K. & O'Nions, R. K., 1999. Zonation of monazite in metamorphic rocks and its implications for high temperature thermochronology: A case study from the Lewisian terrain. Earth and Planetary Science Letters, 171, 209-220.