Bằng chứng cho sự biến chất siêu cao áp đạt chất lượng kim cương và sự tương tác với chất lỏng trong cơ thể garnet peridotite–websterite Fe–Ti Svartberget, Khu vực Gneiss Tây, Na Uy

J. C. Vrijmoed1, H. L. M. Van Roermund2, G. R. Davies1
1Petrology Department, Faculty of Earth and Life Science, Free University Amsterdam, Amsterdam, Netherlands
2Structural Geology Group, Faculty of Earth Sciences, Utrecht University, Utrecht, Netherlands

Tóm tắt

Dựa trên những bằng chứng khoáng vật-hóa học, chúng tôi đề xuất rằng miền biến chất siêu cao áp (UHP) Scandian ở phía bắc trong Khu vực Gneiss Tây của Na Uy có thể được mở rộng 25 km về phía đông bắc. Một cơ thể garnet peridotite loại Fe–Ti mới được phát hiện, bảo tồn tốt và có kết cấu mịn tại Svartberget, nằm trong Ulla Gneiss của khu vực ‘Møre og Romsdal’ phía bắc Molde, bị cắt bởi một mạng lưới các tĩnh mạch garnet-websterite và garnetite dạng hạt thô được định hướng một cách hệ thống. Các kỹ thuật nhiệt áp tiêu chuẩn dựa trên phân tích vi quang điện tử cho ra ước lượng áp suất (P) và nhiệt độ (T) khoảng 3,4 GPa và 800 °C cho cơ thể peridotite và 5,5 GPa và 800 °C cho các tĩnh mạch websterite, phù hợp với điều kiện UHP. Ngoài ra, các tạp chất rắn đa pha, bao gồm silicat, carbonate, sulfate và carbon nguyên tố (bao gồm microdiamond), được định vị ngẫu nhiên trong garnet và clinopyroxene của hợp phần tĩnh mạch websterite. Các cặp khoáng vật garnet-clinopyroxene cho thấy tuổi lạnh Sm–Nd là 393 ± 3 Ma cho peridotite và 381 ± 6 Ma cho hợp phần tĩnh mạch, cho thấy rằng cơ thể Svartberget đã bị ảnh hưởng trong quá trình biến hình UHP của Orogeny Scandian. Tỷ lệ ban đầu của isochron khoáng vật và tuổi mô hình Nd gợi ý nguồn gốc giữa kỷ Proterozoic cho cơ thể peridotite. Các tạp chất đa pha, cùng với tỷ lệ 87Sr/86Sr cao có thể chỉ ra rằng cơ thể peridotite đã bị xâm nhập bởi các dòng/ chất lỏng C–O–H có nguồn gốc từ vỏ trái đất dưới điều kiện UHPM để hình thành các tĩnh mạch websterite trong khu vực có kim cương. Chúng tôi đề xuất rằng việc nứt và sự xuất hiện của tĩnh mạch là kết quả của áp lực chất lỏng cục bộ cao trong quá trình đắm chìm của mảng Baltic.

Từ khóa

#biến chất siêu cao áp #đá peridotite #tĩnh mạch garnet-websterite #áp lực chất lỏng #tỷ lệ 87Sr/86Sr #diamen #Orogeny Scandian

Tài liệu tham khảo

TB Andersen (1998) ArticleTitleExtensional tectonics in the Caledonides of southern Norway, an overview Tectonophysics 285 333–351 Occurrence Handle10.1016/S0040-1951(97)00277-1 H Austrheim F Corfu I Bryhni TB Andersen (2003) ArticleTitleThe Proterozoic Hustad igneous complex: a low strain enclave with a key to the history of the Western Gneiss Region of Norway Precambrian Res 120 149–175 Occurrence Handle10.1016/S0301-9268(02)00167-5 GP Brey T Köhler (1990) ArticleTitleGeothermobarometry in Four-phase Lherzolites. II. New Thermobarometers, and Practical Assessment of Existing Thermobarometers J Petrol 31 1353–1378 Brueckner HK, Van Roermund HLM (2004) Dunk tectonics: a multiple subduction/education model for the evolution of the Scandinavian Caledonides. Tectonics 23, DOI: TC2004, 10.1029/2003TC001502 Bryhni I (1989) Status of the supracrustal rocks in the Western Gneiss Region, S. Norway. In: Gayer RA (ed) The Caledonide Geology of Scandinavia. Graham & Trotman, pp 221–228 Bryhni I, Austrheim H, Solli A (1989) HUSTAD berggrunnskart 1220 1 Norges Geologiske Undersøkelse, Trondheim, foreløpig utgave I Bryhni BA Sturt (1985) Caledonides of southwestern Norway DG Gee BA Sturt (Eds) The Caledonide Orogen; Scandinavia and related areas NumberInSeries1 John Wiley & Sons Chichester, United Kingdom 89–107 FP Bundy (1980) ArticleTitleThe P, T phase and reaction diagram for elemental carbon J Geophys Res 85 6930–6936 Occurrence Handle10.1029/JB085iB12p06930 DA Carswell HK Brueckner SJ Cuthbert K Mehta PJ O’Brien (2003a) ArticleTitleThe timing of stabilisation and the exhumation rate for ultra-high pressure rocks in the Western Gneiss Region of Norway J Metamorph Geol 21 601–612 Occurrence Handle10.1046/j.1525-1314.2003.00467.x DA Carswell SL Harley (1990) Mineral barometry and thermometry DA Carswell (Eds) Eclogite facies rocks Blackie Glasgow 83–110 DA Carswell MA Harvey (1982) ArticleTitleThe intrusive history and tectono-metamorphic evolution of the Basal Gneiss Complex in the Moldefjord region, W. Norway J Geol Soc London 139 368–368 DA Carswell MA Harvey A Al-Samman (1983) ArticleTitleThe petrogenesis of contrasting Fe–Ti and Mg–Cr garnet peridotite types in the high-grade gneiss complex of Western Norway B Mineral 106 727–750 DA Carswell RD Tucker PJ O’Brien TE Krogh (2003b) ArticleTitleCoesite micro-inclusions and the U/Pb age of zircons from the Hareidland eclogite in the Western Gneiss Region of Norway Lithos 67 181–190 Occurrence Handle10.1016/S0024-4937(03)00014-8 DA Carswell HLM Van Roermund (2005) ArticleTitleOn multi-phase mineral inclusions associated with microdiamond formation in mantle-derived peridotite lens at Bardane on Fjortoft, west Norway Eur J Mineral 17 31–42 Occurrence Handle10.1127/0935-1221/2005/0017-0031 Carswell DA, Van Roermund HLM, Wiggers de Vries D (2006) Scandian ultra-high pressure metamorphism of Proterozoic Basement rocks on Fjørtoft and Otrøy in the Western Gneiss Region of Norway. Int Geol Rev Accepted AI Chemenda M Mattauer J Malavieille AN Bokun (1995) ArticleTitleA mechanism for syn-collisional rock exhumation and associated normal faulting – results from physical modeling Earth Planet Sc Lett 132 225–232 Occurrence Handle10.1016/0012-821X(95)00042-B SJ Cuthbert DA Carswell EJ Krogh-Ravna A Wain (2000) ArticleTitleEclogites and eclogites in the Western Gneiss Region, Norwegian Caledonides Lithos 52 165–195 Occurrence Handle10.1016/S0024-4937(99)00090-0 LF Dobrzhinetskaya EA Eide RB Larsen BA Sturt RG Tronnes DC Smith WR Taylor TV Posukhova (1995) ArticleTitleMicrodiamond in high-grade metamorphic rocks of the Western Gneiss Region, Norway Geology 23 597–600 Occurrence Handle10.1130/0091-7613(1995)023<0597:MIHGMR>2.3.CO;2 MH Dodson (1973) ArticleTitleClosure Temperature in Cooling Geochronological and Petrological Systems Contrib Mineral Petrol 40 259–274 Occurrence Handle10.1007/BF00373790 GTR Droop (1987) ArticleTitleA general equation for estimating Fe3+ concentrations in ferromagnesian silicates and oxides from microprobe analyses, using stoichiometric criteria Mineralog Mag 51 431–435 DJ Ellis DH Green (1979) ArticleTitleExperimental-study of the effect of Ca upon garnet-clinopyroxene Fe–Mg exchange equilibria Contrib Mineral Petrol 71 13–22 Occurrence Handle10.1007/BF00371878 WG Ernst (1973) ArticleTitleInterpretative synthesis of metamorphism in Alps Geol Soc Am Bull 84 2053–2078 Occurrence Handle10.1130/0016-7606(1973)84<2053:ISOMIT>2.0.CO;2 J Ganguly M Tirone (1999) ArticleTitleDiffusion closure temperature and age of a mineral with arbitrary extent of diffusion: theoretical formulation and applications Earth Planet Sc Lett 170 131–140 Occurrence Handle10.1016/S0012-821X(99)00089-8 J Ganguly M Tirone RL Hervig (1998) ArticleTitleDiffusion kinetics of samarium and neodymium in garnet, and a method for determining cooling rates of rocks Science 281 805–807 Occurrence Handle10.1126/science.281.5378.805 WL Griffin H Austrheim K Brastad I Bryhni AG Krill EJ Krogh MBE Mørk H Qvale B Torudbakken (1985) High-pressure metamorphism in the Scandinavian Caledonides DG Gee BA Sturt (Eds) The Caledonide Orogen; Scandinavia and related areas NumberInSeries2 John Wiley & Sons Chichester, United Kingdom 783–801 WL Griffin HK Brueckner (1985) ArticleTitleRee, Rb–Sr and Sm–Nd Studies of Norwegian Eclogites Chem Geol 52 249–271 Griselin M (2001) Geochemical and isotopic study of the Xigaze and Luabusa ophiolite massifs (Yarlung Zangbo Suture Zone, Southern Tibet): implications for partial melting and dynamic evolution of the Neo-Tethys Ocean Unpubl. Ph.D. Thesis Vrije Universiteit, Amsterdam, 216 p M Griselin JC van Belle C Pomies PZ Vroon MC van Soest GR Davies (2001) ArticleTitleAn improved chromatographic separation technique of Nd with application to NdO+ isotope analysis Chem Geol 172 347–359 Occurrence Handle10.1016/S0009-2541(00)00256-4 Hacker B, Root D, Walsh E, Young D, Mattinson J (2001) Recent progress on the Norwegian HP-UHP eclogites. Abstract to UHPM Workshop at Waseda University, Japan 4B06: 174 SL Harley (1984a) ArticleTitleAn experimental study of the partitioning of Fe and Mg between garnet and orthopyroxene Contrib Mineral Petrol 86 359–373 Occurrence Handle10.1007/BF01187140 SL Harley (1984b) ArticleTitleThe Solubility of Alumina in Orthopyroxene Coexisting with Garnet in FeO–MgO–Al2O3–SiO2 and CaO–FeO–MgO–Al2O3–SiO2 J Petrol 25 665–696 SL Harley DH Green (1982) ArticleTitleGarnet orthopyroxene barometry for granulites and peridotites Nature 300 697–701 Occurrence Handle10.1038/300697a0 MA Harvey (1983) ArticleTitleA geochemical and Rb–Sr study of the Proterozoic augen orthogneisses on the Molde peninsula, west Norway Lithos 16 325–338 Occurrence Handle10.1016/0024-4937(83)90020-8 BS Hemingway SR Bohlen WB Hankins EF Westrum OL Kuskov (1998) ArticleTitleHeat capacity and thermodynamic properties for coesite and jadeite, reexamination of the quartz-coesite equilibrium boundary Am Mineral 83 409–418 J Hermann (2003) ArticleTitleExperimental evidence for diamond-facies metamorphism in the Dora-Maira massif Lithos 70 163–182 Occurrence Handle10.1016/S0024-4937(03)00097-5 B Jamtveit (1987a) ArticleTitleMagmatic and metamorphic controls on chemical variations within the Eiksunddal eclogite complex, Sunnmore, Western Norway Lithos 20 369–389 Occurrence Handle10.1016/0024-4937(87)90017-X B Jamtveit (1987b) ArticleTitleMetamorphic evolution of the Eiksunddal eclogite complex – Western Norway, and some tectonic implications Contrib Mineral Petrol 95 82–99 Occurrence Handle10.1007/BF00518032 M Krabbendam JF Dewey (1998) ArticleTitleExhumation of UHP rocks by transtension in the Western Gneiss Region, Scandinavian Caledonides Geol Soc Spec Publ 135 159–181 Occurrence Handle10.1144/GSL.SP.1998.135.01.11 AG Krill (1985) Relationships between the Western Gneiss Region and the Trondheim region; stockwerk-tectonics reconsidered DG Gee BA Sturt (Eds) The Caledonide Orogen; Scandinavia and related areas NumberInSeries1 John Wiley & Sons Chichester, United Kingdom 475–483 EJ Krogh (1977) ArticleTitleEvidence of Precambrian continent–continent collision in Western Norway Nature 267 17–19 Occurrence Handle10.1038/267017a0 EJ Krogh (1988) ArticleTitleThe garnet-clinopyroxene Fe–Mg geothermometer – a reinterpretation of existing experimental data Contrib Mineral Petrol 99 44–48 Occurrence Handle10.1007/BF00399364 Krogh EJ, Carswell DA (1995) HP and UHP Eclogites and Garnet Peridotites in the Scandinavian Caledonides. In: Coleman RG, Wang X (eds) Ultrahigh Pressure Metamorphism. Cambridge University Press, pp 244–298 Krogh T, Robinson P, Terry MP (2003) Precise U–Pb zircon ages define 18 and 19 m.y. Subduction to uplift intervals in the Averøya-Nordøyane area, Western Gneiss Region. NGU-report 2003-055: 71–72 HY Lee J Ganguly (1988) ArticleTitleEquilibrium compositions of coexisting garnet and orthopyroxene – experimental determinations in the system FeO–MgO–Al2O3–SiO2, and Applications J Petrol 29 93–113 MBE Mørk (1985a) ArticleTitleA gabbro to eclogite transition on Flemsøy, Sunnmore, Western Norway Chem Geol 50 283–310 Occurrence Handle10.1016/0009-2541(85)90125-1 MBE Mørk (1985b) ArticleTitleIncomplete high P–T metamorphic transitions within the Kvamsøy pyroxenite complex, West Norway – a case-study of disequilibrium J Metamorph Geol 3 245–264 KG Nickel DH Green (1985) ArticleTitleEmpirical geothermobarometry for garnet peridotites and implications for the nature of the lithosphere, kimberlites and diamonds Earth Planet Sc Lett 73 158–170 Occurrence Handle10.1016/0012-821X(85)90043-3 HSC O’Neill (1980) ArticleTitleCorrection Contrib Mineral Petrol 72 337–337 Occurrence Handle10.1007/BF00376154 HSC O’Neill BJ Wood (1979) ArticleTitleExperimental-Study of Fe–Mg Partitioning between garnet and olivine and its calibration as a geothermometer Contrib Mineral Petrol 70 59–70 Occurrence Handle10.1007/BF00371872 R Powell (1985) ArticleTitleRegression diagnostics and robust regression in geothermometer geobarometer calibration – the garnet clinopyroxene geothermometer revisited J Metamorph Geol 3 231–243 A Råheim DH Green (1974) ArticleTitleExperimental determination of the temperature and pressure dependence of the Fe–Mg partition coefficient for coexisting garnet and clinopyroxene Contrib Mineral Petrol 48 179–203 Occurrence Handle10.1007/BF00383355 EJK Ravna (2000) ArticleTitleThe garnet-clinopyroxene Fe2+–Mg geothermometer: an updated calibration J Metamorph Geol 18 211–219 Occurrence Handle10.1046/j.1525-1314.2000.00247.x Ravna EJK, Paquin J (2003) Thermobarometric methodologies applicable to eclogites and garnet ultrabasites. In: Carswell DA, Compagnoni R (eds) Ultrahigh pressure metamorphism, vol. EMU Notes in Mineralogy 5, pp 229–259 D Roberts (2003) ArticleTitleThe Scandinavian Caledonides: event chronology, palaeogeographic settings and likely, modern analogues Tectonophysics 365 283–299 Occurrence Handle10.1016/S0040-1951(03)00026-X P Robinson (1995) ArticleTitleExtension of Trollheimen tectono-stratigraphic sequence in deep synclines near Molde and Brattvåg, Western Gneiss Region, Southern Norway Norsk Geol Tidsskr 75 181–197 DB Root BR Hacker PB Gans MN Ducea EA Eide JL Mosenfelder (2005) ArticleTitleDiscrete ultrahigh-pressure domains in the Western Gneiss Region, Norway: implications for formation and exhumation J Metamorph Geol 23 45–61 Occurrence Handle10.1111/j.1525-1314.2005.00561.x M Sambridge DD Lambert (1997) ArticleTitlePropagating errors in decay equations: examples from the Re–Os isotopic system Geochim Cosmochim Acta 61 3019–3024 Occurrence Handle10.1016/S0016-7037(97)00130-0 Schmidt HH (1963) Petrology and structure of the Eiksundal Eclogite Complex, Hareidlandet, Sunnmore, Norway Unpubl. Ph.D. Thesis Harvard University, U.S.A., 323 p M Seranne (1992) ArticleTitleLate Paleozoic Kinematics of the More-Trondelag Fault Zone and adjacent areas, central Norway Norsk Geol Tidsskr 72 141–158 DC Smith (1984) ArticleTitleCoesite in clinopyroxene in the Caledonides and its implications for geodynamics Nature 310 641–644 Occurrence Handle10.1038/310641a0 P Stalder P Ulmer AB Thompson D Gunther (2000) ArticleTitleExperimental approach to constrain second critical end points in fluid/silicate systems: near-solidus fluids and melts in the system albite-H2O Am Mineral 85 68–77 Terry MP, Robinson P (2003) Evolution of amphibolite-facies structural features and boundary conditions for deformation during exhumation of high- and ultrahigh-pressure rocks, Nordoyane, Western Gneiss Region, Norway. Tectonics 22: 1036, DOI: 10.1029/2001 TC001349 Terry MP, Robinson P (2004) Geometry of eclogite-facies structural features: implications for production and exhumation of ultrahigh-pressure and high-pressure rocks, Western Gneiss Region, Norway. Tectonics 23: TC2001, DOI: 10.1029/2002TC001401 MP Terry P Robinson EJK Ravna (2000) ArticleTitleKyanite eclogite thermobarometry and evidence for thrusting of UHP over HP metamorphic rocks, Nordøyane, Western Gneiss Region, Norway Am Mineral 85 1637–1650 M Thöni (2002) ArticleTitleSm–Nd isotope systematics in garnet from different lithologies (Eastern Alps): age results, and an evaluation of potential problems for garnet Sm–Nd chronometry Chem Geol 185 255–281 Occurrence Handle10.1016/S0009-2541(01)00410-7 TH Torsvik MA Smethurst JG Meert R Van der Voo WS McKerrow MD Brasier BA Sturt HJ Walderhaug (1996) ArticleTitleContinental break-up and collision in the Neoproterozoic and Palaeozoic – a tale of Baltica and Laurentia Earth-Sci Rev 40 229–258 Occurrence Handle10.1016/0012-8252(96)00008-6 Tveten E, Lutro O, Thornes T (1998) Geologisk kart over Norge, berggrunnskart, ÅLESUND 1:250.000 Norges geologiske undersøkelse, Geological map JA Van Orman TL Grove N Shimizu GD Layne (2002) ArticleTitleRare earth element diffusion in a natural pyrope single crystal at 2.8 GPa Contrib Mineral Petrol 142 416–424 HLM Van Roermund DA Carswell MR Drury TC Heijboer (2002) ArticleTitleMicrodiamonds in a megacrystic garnet websterite pod from Bardane on the island of Fjørtoft, western Norway: evidence for diamond formation in mantle rocks during deep continental subduction Geology 30 959–962 Occurrence Handle10.1130/0091-7613(2002)030<0959:MIAMGW>2.0.CO;2 HLM Van Roermund D Spengler D Wiggers de Vries (2005) ArticleTitleEvidence for ultra-high pressure (UHP) metamorphism within Proterozoic basement rocks on Otrøy, Western Gneiss Region, Norway Mitt Osterr Miner Ges 150 159 Van Straaten B, Wiggers de Vries D, Van Roermund HLM, Drury M (2003) A structural, metamorphic and geochronological study of eclogites and country rock gneisses from Otrøy (Moldefjord), WGR, Norway. Norg Geol Unders Report 2003.055: 155–156 Vrijmoed JC, Smith DC, Van Roermund HLM (In preparation) A new in-situ microdiamond locality in the Scandinavian Caledonides: Svartberget PRA Wells (1977) ArticleTitlePyroxene thermometry in simple and complex systems Contrib Mineral Petrol 62 129–139 Occurrence Handle10.1007/BF00372872