Clinoenstatite in Alpe Arami peridotite: Additional evidence of very high pressure

Science

Volumn 284, Issue 5411, 1999, Pages 128-132

  Bozhilov, K N ^a   Green II, H W ^a   Dobrzhinetskaya, L ^a  

^a UNIVERSITY OF CALIFORNIA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

MINERAL;

CLINOENSTATITE; CONTINENTAL COLLISION; EXHUMATION; PERIDOTITE; ULTRAHIGH PRESSURE METAMORPHISM;

ARTICLE; CHEMICAL COMPOSITION; GEOLOGY; MINERALIZATION; PRESSURE; PRIORITY JOURNAL; TRANSMISSION ELECTRON MICROSCOPY;

SWITZERLAND;

EID: 0033515829     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.284.5411.128     Document Type: Article

References (75)

1. L. Dobrzhinetskaya, H. W. Green II, S. Wang, Science 271, 1841 (1996).
2. D. Mosely, Am. Mineral. 66, 976 (1981); H. W. Green II and Y. Gueguen. Tectonophysics 92, 71 (1983); M. R. Drury and H. L. M. van Roermund, Geology 16, 1035 (1988); ibid. 17, 676 (1989).
3. D. Mosely, Am. Mineral. 66, 976 (1981); H. W. Green II and Y. Gueguen. Tectonophysics 92, 71 (1983); M. R. Drury and H. L. M. van Roermund, Geology 16, 1035 (1988); ibid. 17, 676 (1989).
4. D. Mosely, Am. Mineral. 66, 976 (1981); H. W. Green II and Y. Gueguen. Tectonophysics 92, 71 (1983); M. R. Drury and H. L. M. van Roermund, Geology 16, 1035 (1988); ibid. 17, 676 (1989).
5. D. Mosely, Am. Mineral. 66, 976 (1981); H. W. Green II and Y. Gueguen. Tectonophysics 92, 71 (1983); M. R. Drury and H. L. M. van Roermund, Geology 16, 1035 (1988); ibid. 17, 676 (1989).
6. R. L. Hervig, J. V. Smith, J. B. Dawson, Edinb. Trans. Earth Sci. 77, 181 (1986).
7. H. W. Green II, L. Dobrzhinetskaya, E. M. Riggs, Z.-M. Jin, Tectonophysics 279, 1 (1997).
8. J. R. Möckel, Leidse Geol. Med. 42, 61 (1969); J. M. A. Buiskool Toxopeus, ibid. 51, 1 (1976); Neues Jahrb. Miner. Abh. 129, 233 (1977a); Tectonophysics 39, 55 (1977b); E. Den Tex, Fortschr. Miner. 48, 69 (1971).
9. J. R. Möckel, Leidse Geol. Med. 42, 61 (1969); J. M. A. Buiskool Toxopeus, ibid. 51, 1 (1976); Neues Jahrb. Miner. Abh. 129, 233 (1977a); Tectonophysics 39, 55 (1977b); E. Den Tex, Fortschr. Miner. 48, 69 (1971).
10. J. R. Möckel, Leidse Geol. Med. 42, 61 (1969); J. M. A. Buiskool Toxopeus, ibid. 51, 1 (1976); Neues Jahrb. Miner. Abh. 129, 233 (1977a); Tectonophysics 39, 55 (1977b); E. Den Tex, Fortschr. Miner. 48, 69 (1971).
11. J. R. Möckel, Leidse Geol. Med. 42, 61 (1969); J. M. A. Buiskool Toxopeus, ibid. 51, 1 (1976); Neues Jahrb. Miner. Abh. 129, 233 (1977a); Tectonophysics 39, 55 (1977b); E. Den Tex, Fortschr. Miner. 48, 69 (1971).
12. J. R. Möckel, Leidse Geol. Med. 42, 61 (1969); J. M. A. Buiskool Toxopeus, ibid. 51, 1 (1976); Neues Jahrb. Miner. Abh. 129, 233 (1977a); Tectonophysics 39, 55 (1977b); E. Den Tex, Fortschr. Miner. 48, 69 (1971).
13. A. Nicolas and J.-P. Poirier, Crystalline Plasticity and Solid State flow in Metamorphic Rocks (Wiley, New York, 1976); H .W. Green II and S. V. Radcliffe, Earth Planet. Sci. Lett. 15, 239 (1972); Geophys. Monogr. 16, 139 (1972); Y. Gueguen, Tectonophysics 39, 231 (1977); Z.-M. Jin, H. W. Green II, R. S. Borch, ibid. 169 23 (1989).
14. A. Nicolas and J.-P. Poirier, Crystalline Plasticity and Solid State flow in Metamorphic Rocks (Wiley, New York, 1976); H .W. Green II and S. V. Radcliffe, Earth Planet. Sci. Lett. 15, 239 (1972); Geophys. Monogr. 16, 139 (1972); Y. Gueguen, Tectonophysics 39, 231 (1977); Z.-M. Jin, H. W. Green II, R. S. Borch, ibid. 169 23 (1989).
15. A. Nicolas and J.-P. Poirier, Crystalline Plasticity and Solid State flow in Metamorphic Rocks (Wiley, New York, 1976); H .W. Green II and S. V. Radcliffe, Earth Planet. Sci. Lett. 15, 239 (1972); Geophys. Monogr. 16, 139 (1972); Y. Gueguen, Tectonophysics 39, 231 (1977); Z.-M. Jin, H. W. Green II, R. S. Borch, ibid. 169 23 (1989).
16. A. Nicolas and J.-P. Poirier, Crystalline Plasticity and Solid State flow in Metamorphic Rocks (Wiley, New York, 1976); H .W. Green II and S. V. Radcliffe, Earth Planet. Sci. Lett. 15, 239 (1972); Geophys. Monogr. 16, 139 (1972); Y. Gueguen, Tectonophysics 39, 231 (1977); Z.-M. Jin, H. W. Green II, R. S. Borch, ibid. 169 23 (1989).
17. A. Nicolas and J.-P. Poirier, Crystalline Plasticity and Solid State flow in Metamorphic Rocks (Wiley, New York, 1976); H .W. Green II and S. V. Radcliffe, Earth Planet. Sci. Lett. 15, 239 (1972); Geophys. Monogr. 16, 139 (1972); Y. Gueguen, Tectonophysics 39, 231 (1977); Z.-M. Jin, H. W. Green II, R. S. Borch, ibid. 169 23 (1989).
18. C. B. Raleigh, J. Geophys. Res. 73, 5391 (1968); N. L. Carter and H. G. Ave'Lallement, Geol. Soc. Am. Bull. 81, 2181 (1970); D. L. Kohlstedt and C. Goetze, J. Geophys. Res. 79, 2045 (1974); W. Durham, C. Goetze, B. Blake, ibid. 82, 5755 (1977); D. H. Zeuch and H. W. Green II, Tectonophysics 110, 263 (1984); H. W. Green II, in Electron Microscopy in Mineralogy, H.-R. Wenk et al., Eds. (Springer-Verlag Berlin, Heidelberg, 1976), pp. 443-464.
19. C. B. Raleigh, J. Geophys. Res. 73, 5391 (1968); N. L. Carter and H. G. Ave'Lallement, Geol. Soc. Am. Bull. 81, 2181 (1970); D. L. Kohlstedt and C. Goetze, J. Geophys. Res. 79, 2045 (1974); W. Durham, C. Goetze, B. Blake, ibid. 82, 5755 (1977); D. H. Zeuch and H. W. Green II, Tectonophysics 110, 263 (1984); H. W. Green II, in Electron Microscopy in Mineralogy, H.-R. Wenk et al., Eds. (Springer-Verlag Berlin, Heidelberg, 1976), pp. 443-464.
20. C. B. Raleigh, J. Geophys. Res. 73, 5391 (1968); N. L. Carter and H. G. Ave'Lallement, Geol. Soc. Am. Bull. 81, 2181 (1970); D. L. Kohlstedt and C. Goetze, J. Geophys. Res. 79, 2045 (1974); W. Durham, C. Goetze, B. Blake, ibid. 82, 5755 (1977); D. H. Zeuch and H. W. Green II, Tectonophysics 110, 263 (1984); H. W. Green II, in Electron Microscopy in Mineralogy, H.-R. Wenk et al., Eds. (Springer-Verlag Berlin, Heidelberg, 1976), pp. 443-464.
21. C. B. Raleigh, J. Geophys. Res. 73, 5391 (1968); N. L. Carter and H. G. Ave'Lallement, Geol. Soc. Am. Bull. 81, 2181 (1970); D. L. Kohlstedt and C. Goetze, J. Geophys. Res. 79, 2045 (1974); W. Durham, C. Goetze, B. Blake, ibid. 82, 5755 (1977); D. H. Zeuch and H. W. Green II, Tectonophysics 110, 263 (1984); H. W. Green II, in Electron Microscopy in Mineralogy, H.-R. Wenk et al., Eds. (Springer-Verlag Berlin, Heidelberg, 1976), pp. 443-464.
22. C. B. Raleigh, J. Geophys. Res. 73, 5391 (1968); N. L. Carter and H. G. Ave'Lallement, Geol. Soc. Am. Bull. 81, 2181 (1970); D. L. Kohlstedt and C. Goetze, J. Geophys. Res. 79, 2045 (1974); W. Durham, C. Goetze, B. Blake, ibid. 82, 5755 (1977); D. H. Zeuch and H. W. Green II, Tectonophysics 110, 263 (1984); H. W. Green II, in Electron Microscopy in Mineralogy, H.-R. Wenk et al., Eds. (Springer-Verlag Berlin, Heidelberg, 1976), pp. 443-464.
23. C. B. Raleigh, J. Geophys. Res. 73, 5391 (1968); N. L. Carter and H. G. Ave'Lallement, Geol. Soc. Am. Bull. 81, 2181 (1970); D. L. Kohlstedt and C. Goetze, J. Geophys. Res. 79, 2045 (1974); W. Durham, C. Goetze, B. Blake, ibid. 82, 5755 (1977); D. H. Zeuch and H. W. Green II, Tectonophysics 110, 263 (1984); H. W. Green II, in Electron Microscopy in Mineralogy, H.-R. Wenk et al., Eds. (Springer-Verlag Berlin, Heidelberg, 1976), pp. 443-464.
24. A. C. Risold, V. Trommsdorff, E. Reusser, P. Ulmer, B. Grobety, Trans. AGU 77, F761 (1996); A. C. Risold, V. Trommsdorff, E. Reusser, P. Ulmer, M. Pfiffner, Eur. Geophys. Union 9, 93 (1997); B. Hacker, T. Sharp, R. Y. Zhang, J. G. Liou, R. L. Hervig, Science 278, 702 (1997); H. W. Green II, L. Dobrzhinetskaya, K. Bozhilov, ibid., p. 704.
25. A. C. Risold, V. Trommsdorff, E. Reusser, P. Ulmer, B. Grobety, Trans. AGU 77, F761 (1996); A. C. Risold, V. Trommsdorff, E. Reusser, P. Ulmer, M. Pfiffner, Eur. Geophys. Union 9, 93 (1997); B. Hacker, T. Sharp, R. Y. Zhang, J. G. Liou, R. L. Hervig, Science 278, 702 (1997); H. W. Green II, L. Dobrzhinetskaya, K. Bozhilov, ibid., p. 704.
26. A. C. Risold, V. Trommsdorff, E. Reusser, P. Ulmer, B. Grobety, Trans. AGU 77, F761 (1996); A. C. Risold, V. Trommsdorff, E. Reusser, P. Ulmer, M. Pfiffner, Eur. Geophys. Union 9, 93 (1997); B. Hacker, T. Sharp, R. Y. Zhang, J. G. Liou, R. L. Hervig, Science 278, 702 (1997); H. W. Green II, L. Dobrzhinetskaya, K. Bozhilov, ibid., p. 704.
27. A. C. Risold, V. Trommsdorff, E. Reusser, P. Ulmer, B. Grobety, Trans. AGU 77, F761 (1996); A. C. Risold, V. Trommsdorff, E. Reusser, P. Ulmer, M. Pfiffner, Eur. Geophys. Union 9, 93 (1997); B. Hacker, T. Sharp, R. Y. Zhang, J. G. Liou, R. L. Hervig, Science 278, 702 (1997); H. W. Green II, L. Dobrzhinetskaya, K. Bozhilov, ibid., p. 704.
28. Y. Yamaguchi, J. Akai, K. Tomita, Contrib. Mineral. Petrol. 66, 263 (1978).
29. Doubly polished 30-μm-thick sections were prepared, portions of which were mounted on single-hole diamond grids and ion milled at 5 kV with argon plasma beams until the sample was perforated. TEM was performed at the University of California, Riverside, on a Philips CM300 transmission electron microscope operating at an accelerating voltage of 300 kV and equipped with an EDAX energy dispersive spectrometer with Si detector and super-ultrathin window, which allows detection and quantification of Light elements such as oxygen. The parametertess method of E. Van Cappellen [Microsc. Microanal. Microstruct. 1. 1 (1990)] was used to determine experimental k factors, and the quantification procedure included a thickness correction assuming stoichiometry of oxygen [E. Van Cappellen and J.-C. Doukhan, Ultramicroscopy 53, 343 (1994)].
30. Doubly polished 30-μm-thick sections were prepared, portions of which were mounted on single-hole diamond grids and ion milled at 5 kV with argon plasma beams until the sample was perforated. TEM was performed at the University of California, Riverside, on a Philips CM300 transmission electron microscope operating at an accelerating voltage of 300 kV and equipped with an EDAX energy dispersive spectrometer with Si detector and super-ultrathin window, which allows detection and quantification of Light elements such as oxygen. The parametertess method of E. Van Cappellen [Microsc. Microanal. Microstruct. 1. 1 (1990)] was used to determine experimental k factors, and the quantification procedure included a thickness correction assuming stoichiometry of oxygen [E. Van Cappellen and J.-C. Doukhan, Ultramicroscopy 53, 343 (1994)].
31. K. N. Bozhilov, H. W. Green II, L. Dobrzhinetskaya, data not shown.
32. The amphibole structure was confirmed by electron diffraction and HRTEM imaging. The amphibole slabs are typically one to two unit cells thick parallel to b; in rare cases they reach a thickness of about 10 unit cells. In some cases, generally near the dinoenstatite lamellae tips, the amphibole slabs traverse the lamellae. Mostly, however, they run up to the lamellae boundaries and go around them, as typically observed during the hydration of complex exsolved pyroxenes [D. R. Veblen and P. R. Buseck, Am. Mineral. 65, 599 (1980), D. R. Veblen and D. L. Bish, ibid. 73, 677 (1988), K. J. T. Livi and D. R. Veblen, ibid. 74, 1070 (1989)].
33. The amphibole structure was confirmed by electron diffraction and HRTEM imaging. The amphibole slabs are typically one to two unit cells thick parallel to b; in rare cases they reach a thickness of about 10 unit cells. In some cases, generally near the dinoenstatite lamellae tips, the amphibole slabs traverse the lamellae. Mostly, however, they run up to the lamellae boundaries and go around them, as typically observed during the hydration of complex exsolved pyroxenes [D. R. Veblen and P. R. Buseck, Am. Mineral. 65, 599 (1980), D. R. Veblen and D. L. Bish, ibid. 73, 677 (1988), K. J. T. Livi and D. R. Veblen, ibid. 74, 1070 (1989)].
34. The amphibole structure was confirmed by electron diffraction and HRTEM imaging. The amphibole slabs are typically one to two unit cells thick parallel to b; in rare cases they reach a thickness of about 10 unit cells. In some cases, generally near the dinoenstatite lamellae tips, the amphibole slabs traverse the lamellae. Mostly, however, they run up to the lamellae boundaries and go around them, as typically observed during the hydration of complex exsolved pyroxenes [D. R. Veblen and P. R. Buseck, Am. Mineral. 65, 599 (1980), D. R. Veblen and D. L. Bish, ibid. 73, 677 (1988), K. J. T. Livi and D. R. Veblen, ibid. 74, 1070 (1989)].
35. Viewed down b, brightfield images and darkfield images with h + k = even show very similar mottling of contrast within clinoenstatite lamellae; the size, shape, and orientation of contrast domains are the same. Figure 3 shows that this mottling is primarily due to inhomogeneous elastic distortion. For example, the (100) fringes in the brightest region of Fig. 3 are rotated clockwise relative to the domains on either side of it. There are no crystal defects associated with the boundaries of the bright region. In addition, the fringe terminations do not show long-range strain fields; they do not represent dislocations. Therefore, the fringe offsets are growth features; symmetry rules forbid them to be a consequence of elastic strain.
36. M. Cameron and J. J. Papike, Am. Mineral. 66, 1 (1981); R. E. G. Pacalo and T. Gasparik, J. Geophys. Res. 95, 15853 (1990); R. J. Angel, A. Chopelas, N. L. Ross, Nature 358, 322 (1992); R. J. Angel and D. A. Hugh-Jones, J. Geophys. Res. 99, 19777 (1994); D. Hugh-Jones, A. B. Woodland, R. J. Angel, Am. Mineral. 79, 1032 (1994); D. Hugh-Jones, T. Sharp, R. Angel, A. Woodland, Eur. J. Mineral. 8, 1337 (1996).
37. M. Cameron and J. J. Papike, Am. Mineral. 66, 1 (1981); R. E. G. Pacalo and T. Gasparik, J. Geophys. Res. 95, 15853 (1990); R. J. Angel, A. Chopelas, N. L. Ross, Nature 358, 322 (1992); R. J. Angel and D. A. Hugh-Jones, J. Geophys. Res. 99, 19777 (1994); D. Hugh-Jones, A. B. Woodland, R. J. Angel, Am. Mineral. 79, 1032 (1994); D. Hugh-Jones, T. Sharp, R. Angel, A. Woodland, Eur. J. Mineral. 8, 1337 (1996).
38. M. Cameron and J. J. Papike, Am. Mineral. 66, 1 (1981); R. E. G. Pacalo and T. Gasparik, J. Geophys. Res. 95, 15853 (1990); R. J. Angel, A. Chopelas, N. L. Ross, Nature 358, 322 (1992); R. J. Angel and D. A. Hugh-Jones, J. Geophys. Res. 99, 19777 (1994); D. Hugh-Jones, A. B. Woodland, R. J. Angel, Am. Mineral. 79, 1032 (1994); D. Hugh-Jones, T. Sharp, R. Angel, A. Woodland, Eur. J. Mineral. 8, 1337 (1996).
39. M. Cameron and J. J. Papike, Am. Mineral. 66, 1 (1981); R. E. G. Pacalo and T. Gasparik, J. Geophys. Res. 95, 15853 (1990); R. J. Angel, A. Chopelas, N. L. Ross, Nature 358, 322 (1992); R. J. Angel and D. A. Hugh-Jones, J. Geophys. Res. 99, 19777 (1994); D. Hugh-Jones, A. B. Woodland, R. J. Angel, Am. Mineral. 79, 1032 (1994); D. Hugh-Jones, T. Sharp, R. Angel, A. Woodland, Eur. J. Mineral. 8, 1337 (1996).
40. M. Cameron and J. J. Papike, Am. Mineral. 66, 1 (1981); R. E. G. Pacalo and T. Gasparik, J. Geophys. Res. 95, 15853 (1990); R. J. Angel, A. Chopelas, N. L. Ross, Nature 358, 322 (1992); R. J. Angel and D. A. Hugh-Jones, J. Geophys. Res. 99, 19777 (1994); D. Hugh-Jones, A. B. Woodland, R. J. Angel, Am. Mineral. 79, 1032 (1994); D. Hugh-Jones, T. Sharp, R. Angel, A. Woodland, Eur. J. Mineral. 8, 1337 (1996).
41. M. Cameron and J. J. Papike, Am. Mineral. 66, 1 (1981); R. E. G. Pacalo and T. Gasparik, J. Geophys. Res. 95, 15853 (1990); R. J. Angel, A. Chopelas, N. L. Ross, Nature 358, 322 (1992); R. J. Angel and D. A. Hugh-Jones, J. Geophys. Res. 99, 19777 (1994); D. Hugh-Jones, A. B. Woodland, R. J. Angel, Am. Mineral. 79, 1032 (1994); D. Hugh-Jones, T. Sharp, R. Angel, A. Woodland, Eur. J. Mineral. 8, 1337 (1996).
42. N. Morimoto and M. Tokonami, Am. Mineral. 54, 725 (1969); J. C. Bailey et al., Proc. Apollo 11 Lunar Sci. Conf. 1, 169 (1970); G. L. Nord, A. H. Heuer, J. S. Lally, in Electron Microscopy in Mineralogy, H.-R. Wenk, Ed. (Springer-Verlag, New York, 1976), pp. 220-227; M. A. Carpenter, Phys. Chem. Miner. 5, 119 (1979); P. R. Buseck, G. L. Nord, D. R. Veblen, in Pyroxenes, Reviews in Mineralogy, C. T. Prewitt Ed. (Mineralogical Society of America, Washington, DC, 1980), pp. 117-211; K. T. J. Livi and D. R. Veblen, Am. Mineral. 74. 1070 (1989).
43. N. Morimoto and M. Tokonami, Am. Mineral. 54, 725 (1969); J. C. Bailey et al., Proc. Apollo 11 Lunar Sci. Conf. 1, 169 (1970); G. L. Nord, A. H. Heuer, J. S. Lally, in Electron Microscopy in Mineralogy, H.-R. Wenk, Ed. (Springer-Verlag, New York, 1976), pp. 220-227; M. A. Carpenter, Phys. Chem. Miner. 5, 119 (1979); P. R. Buseck, G. L. Nord, D. R. Veblen, in Pyroxenes, Reviews in Mineralogy, C. T. Prewitt Ed. (Mineralogical Society of America, Washington, DC, 1980), pp. 117-211; K. T. J. Livi and D. R. Veblen, Am. Mineral. 74. 1070 (1989).
44. N. Morimoto and M. Tokonami, Am. Mineral. 54, 725 (1969); J. C. Bailey et al., Proc. Apollo 11 Lunar Sci. Conf. 1, 169 (1970); G. L. Nord, A. H. Heuer, J. S. Lally, in Electron Microscopy in Mineralogy, H.-R. Wenk, Ed. (Springer-Verlag, New York, 1976), pp. 220-227; M. A. Carpenter, Phys. Chem. Miner. 5, 119 (1979); P. R. Buseck, G. L. Nord, D. R. Veblen, in Pyroxenes, Reviews in Mineralogy, C. T. Prewitt Ed. (Mineralogical Society of America, Washington, DC, 1980), pp. 117-211; K. T. J. Livi and D. R. Veblen, Am. Mineral. 74. 1070 (1989).
45. N. Morimoto and M. Tokonami, Am. Mineral. 54, 725 (1969); J. C. Bailey et al., Proc. Apollo 11 Lunar Sci. Conf. 1, 169 (1970); G. L. Nord, A. H. Heuer, J. S. Lally, in Electron Microscopy in Mineralogy, H.-R. Wenk, Ed. (Springer-Verlag, New York, 1976), pp. 220-227; M. A. Carpenter, Phys. Chem. Miner. 5, 119 (1979); P. R. Buseck, G. L. Nord, D. R. Veblen, in Pyroxenes, Reviews in Mineralogy, C. T. Prewitt Ed. (Mineralogical Society of America, Washington, DC, 1980), pp. 117-211; K. T. J. Livi and D. R. Veblen, Am. Mineral. 74. 1070 (1989).
46. N. Morimoto and M. Tokonami, Am. Mineral. 54, 725 (1969); J. C. Bailey et al., Proc. Apollo 11 Lunar Sci. Conf. 1, 169 (1970); G. L. Nord, A. H. Heuer, J. S. Lally, in Electron Microscopy in Mineralogy, H.-R. Wenk, Ed. (Springer-Verlag, New York, 1976), pp. 220-227; M. A. Carpenter, Phys. Chem. Miner. 5, 119 (1979); P. R. Buseck, G. L. Nord, D. R. Veblen, in Pyroxenes, Reviews in Mineralogy, C. T. Prewitt Ed. (Mineralogical Society of America, Washington, DC, 1980), pp. 117-211; K. T. J. Livi and D. R. Veblen, Am. Mineral. 74. 1070 (1989).
47. N. Morimoto and M. Tokonami, Am. Mineral. 54, 725 (1969); J. C. Bailey et al., Proc. Apollo 11 Lunar Sci. Conf. 1, 169 (1970); G. L. Nord, A. H. Heuer, J. S. Lally, in Electron Microscopy in Mineralogy, H.-R. Wenk, Ed. (Springer-Verlag, New York, 1976), pp. 220-227; M. A. Carpenter, Phys. Chem. Miner. 5, 119 (1979); P. R. Buseck, G. L. Nord, D. R. Veblen, in Pyroxenes, Reviews in Mineralogy, C. T. Prewitt Ed. (Mineralogical Society of America, Washington, DC, 1980), pp. 117-211; K. T. J. Livi and D. R. Veblen, Am. Mineral. 74. 1070 (1989).
48. 1/c transformation with an overstepping of the phase boundary by ∼1 GPa (14). The most striking differences between HTclen and HPclen are in density (Δp ∼ 3%) and in the different degree of kinking of the silicate tetrahedral chains [expressed macroscopically as different angles of monoclinicity (β) ∼110° in HTclen and ∼101° in Hpclen].
49. P. Robinson, M. Ross, G. L. Nord Jr., J. R. Smyth, H. W. Jaffe, Am. Mineral. 62, 857 (1977).
50. T. Gasparik, ibid. 75, 1080 (1990).
51. S. Iijima and P. R. Buseck, ibid. 60, 758 (1975); P. E. Champness and P. A. Copley, in Electron Microscopy in Mineralogy, H.-R. Wenk, Ed. (Springer-Verlag, New York, 1976), pp. 228-233.; H. Boysen, F. Frey, H. Schrader, G. Eckold, Eur. J. Mineral. 17, 629, (1991).
52. S. Iijima and P. R. Buseck, ibid. 60, 758 (1975); P. E. Champness and P. A. Copley, in Electron Microscopy in Mineralogy, H.-R. Wenk, Ed. (Springer-Verlag, New York, 1976), pp. 228-233.; H. Boysen, F. Frey, H. Schrader, G. Eckold, Eur. J. Mineral. 17, 629, (1991).
53. S. Iijima and P. R. Buseck, ibid. 60, 758 (1975); P. E. Champness and P. A. Copley, in Electron Microscopy in Mineralogy, H.-R. Wenk, Ed. (Springer-Verlag, New York, 1976), pp. 228-233.; H. Boysen, F. Frey, H. Schrader, G. Eckold, Eur. J. Mineral. 17, 629, (1991).
54. R. S. Coe and S. H. Kirby. Contrib. Mineral. Petrol. 52, 29 (1975).
55. G. L. Nord Jr., Rev. Mineral. 27, 455 (1992).
56. H. Feuer, L. Schöpfer, H. Fuess, D. A. Jefferson, Eur. J. Mineral. 1, 507 (1989).
57. H. W. Jaffe, P. Robinson, R. J. Tracy, Am. Mineral. 60, 9 (1975); F. J. Rietmeijer and P. E. Champness, Min. Mag. 45, 11, (1982).
58. H. W. Jaffe, P. Robinson, R. J. Tracy, Am. Mineral. 60, 9 (1975); F. J. Rietmeijer and P. E. Champness, Min. Mag. 45, 11, (1982).
59. W. C. Ernst, J. Petrol. 19, 341 (1978); W. G. Ernst, Am. Mineral. 66, 443 (1981).
60. W. C. Ernst, J. Petrol. 19, 341 (1978); W. G. Ernst, Am. Mineral. 66, 443 (1981).
61. L. G. Medaris and D. A. Carswell, in Eclogite Facies Rocks, D. A. Carswell, Ed. (Blackie, Glasgow, UK, 1990), pp. 250-290; H. Becker, Geology 21, 599 (1993).
62. L. G. Medaris and D. A. Carswell, in Eclogite Facies Rocks, D. A. Carswell, Ed. (Blackie, Glasgow, UK, 1990), pp. 250-290; H. Becker, Geology 21, 599 (1993).
63. F. E. Brenker and G. P. Brey, J. Metamorph. Geol. 15, 581 (1997).
64. The generally close association between the boundaries of strain domains and arrays of lattice fringe offsets within clinoenstatite lamellae suggests a relationship between them. Figure 1, B and C, and Fig. 2A show that the scale of strain inhomogeneity in the lamellae is grossly different from that in the host and that the latter is related to the presence of the lamellae. There are no similar strain effects in diopside crystals that lack clinoenstatite lamellae, nor are such effects present within or around amphibole lamellae. A natural explanation for these correlations and the strain itself is the possibility that the strain pattern is a consequence of the 3% volume expansion that accompanies the HPclen→Lclen inversion. Multiple nucleation sites of the stable phase along the host-daughter interface would lead to "puckering" of the lattice due to local anisotropic expansion in a lamella contained within an essentially rigid framework (its coherent boundaries with the host). The regions of greatest curvature could, in turn, prejudice nucleation of additional antiphase domains. This scenario, although not a proven process, is consistent with the available evidence and provides a reasonable explanation for the pattern of strain and its relationship to the antiphase boundaries.
65. C. Herzberg and T. Gasparik, J. Geophys. Res. 96, 16263 (1991); A. B. Woodland and H. St. C. O'Neill, Contrib. Mineral. Petrol. 121, 87 (1995).
66. C. Herzberg and T. Gasparik, J. Geophys. Res. 96, 16263 (1991); A. B. Woodland and H. St. C. O'Neill, Contrib. Mineral. Petrol. 121, 87 (1995).
67. A. B. Woodland and R. J. Angel, Eur. J. Mineral, 9, 245 (1997); A. B. Woodland, Geophys. Res. Lett. 25, 1241 (1998).
68. A. B. Woodland and R. J. Angel, Eur. J. Mineral, 9, 245 (1997); A. B. Woodland, Geophys. Res. Lett. 25, 1241 (1998).
69. 2 concentrations of 0.6 weight % or more in olivine were measured for temperature >1650 K at 10 GPa and temperature ≥1500 K at 12 GPa.
70. S. E. Haggerty, Eos Trans. AGU 75, 192 (1994).
71. D. Gebauer, M. Grunenfelder, G. R. Tilton, V. Trommsdorff, Terra Abstr. 6, 5 (1993); D. Gebauer, 1st Workshop on UHP Metamorphism and Tectonics, abstract A-67 (Stanford University, Stanford, CA, 1994).
72. D. Gebauer, M. Grunenfelder, G. R. Tilton, V. Trommsdorff, Terra Abstr. 6, 5 (1993); D. Gebauer, 1st Workshop on UHP Metamorphism and Tectonics, abstract A-67 (Stanford University, Stanford, CA, 1994).
73. H. L M. van Roermund and M. R. Drury, Eos Trans. AGU 79, F971 (1998); H. L M. van Roermund, M. R. Drury, A. Barnhoorn, A. De Ronde, Terra Nova, in press.
74. H. L M. van Roermund and M. R. Drury, Eos Trans. AGU 79, F971 (1998); H. L M. van Roermund, M. R. Drury, A. Barnhoorn, A. De Ronde, Terra Nova, in press.
75. This work was partially supported by NSF grants EAR94-13517 and EAR96-283432. We thank R. J. Angel, F. E. Brenker, W. G. Ernst, B. Hacker, G. Nord, C. Prewitt, P. Robinson, N. L. Ross, T. Sharp, H. L. M. van Roermund, A. B. Woodland, and two anonymous reviewers for helpful discussions and suggestions.