Wstępne wyniki badań petrograficznych archaicznych gnejsów Uivak (Prowincja Nain, Labrador)

• Autorzy: Sałacińska A. , Kusiak M. A.

Warianty tytułu

EN

Preliminary petrographic studies of the Archaean Uivak gneisses, Nain Province, Labrador

• Języki publikacji: PL

Abstrakty

EN

The Saglek Block of the Nain Complex in Northern Labrador forms the westernmost part of the North Atlantic Craton. It is one of the few regions on Earth where early Archaean crust is preserved. It consists of regionally metamorphosed gneisses to either granulite-facies from 2.74 to 2.71 Ga or amphibolite-facies at ca. 2.70 Ga. The Saglek Block is dominated by two suites of metaigneous gneisses: the Uivak I TTG suite (>3.6 Ga) and the Uivak II augen gneisses (ca. 3.4 Ga). Four samples offelsic Uivak I orthogneiss were selected to petrographi- cal and mineralogical studies: Johannes Point Cove (L1419), TigigakyukInlet (L1434; L1440) and Big Island (L1443). Sample composition (granodiorite-tonalite) and mineralogy (mostly plagioclase and quartz, with minor K-feldspar and biotite, and accessory zircon and apatite) for three of the four samples are consistent with published data of the Uivak I gneiss. Sample L1434 contains ferroean diopside and hornblende, which are absent in the other samples. Based on detailed mineralogical analyses, authors concluded that more mafic sample, can not belong to the suite of the Uivak I gneisses. Most probably it represents the younger Uivak II. Further, geochronological study is going to be conducted to characterise both, Uivak I and Uivak II gneisses isotopically.

Słowa kluczowe

PL

Ziemia; gnejs; archaik; blok Saglek; Labrador

EN

early Earth; gneisses; Archean; Saglek Block; Labrador

• Wydawca: Państwowy Instytut Geologiczny - Państwowy Instytut Badawczy
• Czasopismo: Przegląd Geologiczny
• Rocznik: 2017
• Tom: Vol. 65, nr 6
• Strony: 383--391
• Opis fizyczny: Bibliogr. 31 poz., rys., tab.

Twórcy

autor

Sałacińska A.

• Instytut Nauk Geologicznych Polskiej Akademii Nauk, ul. Twarda 51/55, 00-818 Warszawa

autor

Kusiak M. A.

• Instytut Nauk Geologicznych Polskiej Akademii Nauk, ul. Twarda 51/55, 00-818 Warszawa

Bibliografia

• 1. BAADSGAARD H., COLLERSON K.D. & BRIDGWATER, D. 1979 - The Archaean gneiss complex of northern Labrador. 1. Preliminary U-Th-Pb geochronology. Can. J. Earth Sci., 16 (4): 951-961.
• 2. BRIDGWATER D. & COLLERSON K.D. 1976 - Major petrological and geochemical characters of 3,600 my Uivak gneisses from Labrador. Contrib. Mineral. Petrol., 54: 43-59.
• 3. BRIDGWATER D., COLLERSON K.D., HURST R.W. & JESSEAU C.W. 1975 - Field characters of the early Precambrian rocks from Saglek, coast of Labrador. Geol. Sum. Can., Pap. 75-1, Part A: 287-296.
• 4. BRIDGWATER D., MENGEL F., SCHIOTTE L. & WINTER J. 1990 - Research on the Archean rocks of northern Labrador, progress report 1989: Current Research. New foundland Department of Mines and Energy, Report 90-1: 227-236.
• 5. BRIDGWATER D. & SCHIOTTE L. 1991 - The Archaean gneiss complex of Northern Labrador - A review of current results, ideas and problems. Bull. Geol. Soc., Denmark: 39: 153-166.
• 6. BRIDGWATER D., WATSON J. & WINDLEYB.F. 1973 - The Archaean craton of the North Atlantic region. Phil. Trans. Roy Soc. London, Ser. A, 273: 493-512.
• 7. COLLERSON K.D. 1983 - Ion microprobe zircon geochronology of the Uivak gneisses: implications for the evolution of early terrestrial crust in the North Atlantic Craton, Houston, Texas. Lunar and Planetary Institute Technical, Report 83-03: 28-33.
• 8. COLLERSON K.D. & BRIDGWATER D. 1979 - Metamorphic development of early Archean tonalitic and trondhjemitic gneisses, Saglek area, Labrador. [W:] Baker F. (red.), Trondhjemites, dacites and related rocks. Amsterdam, Elsevier, 205-273.
• 9. COLLERSON K.D., KERR A., VOCKE R.D. & HANSON G.N. 1982 - Reworking of sialic crust as represented in late Archaean-age gneisses, northern Labrador. Geology, 10: 202-208.
• 10. COLLERSON K.D., MEROZ Y. & GIL C. 1992 - Early Archean lithosphere: Constraints from the North Atlantic Craton (abstr.). Eos, 73: 330.
• 11. CONDIE K.C. 1981 - Archaean Greenstone Belts. Amsterdam, Elsevier, s. 434.
• 12. DROOP G.T.R. 1987 - A general equation for estimating Fe3+ concentrations in ferromagnesian silicates and oxides from microprobe analyses using stoichiometric criteria. Mineral. Mag., 51 (361): 431-435.
• 13. ERMANOVICS I.F., VAN KRANENDONK M.J., CORRIVEAU L., MENGEL F., BRIDGWATER D. & SHERLOCK R. 1988 - Geology of North River-Nutak map areas, Nain-Churchill provinces, Labrador. In Current Res., Part C. Geol. Surv. Can., 88-1C: 19-26.
• 14. ERMANOVICS I.F., VAN KRANENDONK M.J., CORRIVEAU L., MENGEL F., BRIDGWATER D. & SHERLOCK R. 1989 - The boundary zone of the Nain-Churchill provinces in the North River-Nutak map areas, Labrador. Geol. Surv. Can., Report 89-1C: 385-394.
• 15. HAWTHORNE F.C., OBERTI R., HARLOW G.E., MARESCH W.V., MARTIN R.F., SCHUMACHER J.C. & WELCH M.D. 2012 - IMA report, nomenclature of the amphibole supergroup. Am. Mineral., 97: 2031-2048.
• 16. HURST R.W., BRIDGWATER D., COLLERSON K.D. & WETHERILL G.W. 1975 - 3600 m.y. Rb-Sr ages from very early Archaean gneisses from Saglek Bay, Labrador. Earth Planet. Sci. Lett., 27: 393-403.
• 17. KROGH T.E. & KAMO S.L. 2006 - Precise U-Pb zircon ID-TIMS ages provide an alternative interpretation to early ion microprobe ages and new insights into Archean crustal processes, northern Labrador. Geol. Soc. Amer. Spec. Pap., 405: 91-103.
• 18. KOMIYA T., YAMAMOTO S., AOKIA S., SAWAKI Y., ISHIKAWA A., TASHIRO T., KOSHIDA K., SHIMOJO M., AOKIK. & COLLERSON K.D. 2015 - Geology of the Eoarchean, > 3.95 Ga, Nulliak supracrustal rocks in the Saglek Block, northern Labrador, Canada: The oldest geological evidence for plate tectonics. Tectonophysics, 622: 4-66.
• 19. KOMIYA T., YAMAMOTO S., AOKI S., KOSHIDA K., SHIMOJO M., SAWAKI Y., AOKI K., SAKATA S., YOKOYAMA T.D., MAKI K., ISHIKAWA A., HIRATA T. & COLLERSON K.D. 2016 - A prolonged granitoid formation in Saglek Block, Labrador: Zonal growth and crustal reworking of continental crust in the Eoarchean. Geoscience Frontiers. Doi: 10.1016/j.gsf.2016.06.013.
• 20. KUSIAK M.A. & SAŁACIŃSKA A. 2016 - W poszukiwaniu fragmentów najstarszej skorupy kontynentalnej na Labradorze. Prz. Geol., 64 (11): 896-901.
• 21. LOCOCK A.J. 2014 - An Excel spreadsheet to classify chemical analyses of amphiboles following the IMA2012 recommendations. Computers & Geosciences, 62: 1-11.
• 22. MORGAN W.C. 1975 - Geology of the Precambrian Ramah Group and basement rocks in the Nachvak Fiord-Saglek Fiord area, north Labrador. Geol. Surv. Can., 74-54: 42.
• 23. MORIMOTO N. 1989 - Nomenclature of pyroxenes. Can. Mineral., 27: 143-156.
• 24. REGELOUS M. & COLLERSON K.D. 1996 - Sm-147-Nd-143, Sm-146-Nd-142 systematics of Early Archaean rocks and implications for crust-mantle evolution. Geochim. Cosmochim. Acta, 60: 3513-3520.
• 25. RIEDER M., CAVAZZINI G., D’YAKONOV Y.S., FRANK-KAMENETSKII V.A., GOTTARDI G., GUGGENHEIM S., KOVAL P.V., MULLER G., NEIVA A.M.R., RADOSLOVICH E.W., ROBERT J.L., SASSI F.P., TAKEDA H., WEISS Z. & WONES D.R. 1998 - Nomenclature of the micas. Can. Mineral., 36: 41-48.
• 26. RYAN B. 1990 - Basement-cover relationships and metamorphic patterns in the foreland of the Torngat Orogen in the Saglek Hebron area, Labrador. Geoscience Canada, 17: 276-279.
• 27. RYAN A.R., MARTINEAU Y., KORSTGAARD J. & LEE D. 1984 - The Archean - Proterozoic boundary in northern Labrador, report 2. Current Research. Report, 84-1: 12-20.
• 28. SCHIOTTE L., COMPSTON W. & BRIDGWATER D. 1989 - Ion-probe U-Th-Pb zircon dating of polymetamorphic orthogneisses from northern Labrador, Canada. Can. J. Earth Sci., 26: 1533-1556.
• 29. SHIMOJO M., YAMAMOTO S., SAKATA S., YOKOYAMA T.D., MAKI K., SAWAKI Y., ISHIKAWA A., AOKI K., AOKI S., KOSHIDA K., TASHIRO T., HIRATA T., COLLERSON K.D. & KOMIYA T. 2016 - Occurrence and geochronology of the Eoarchean, ~3.9 Ga, Iqaluk Gneiss in the Saglek Block, northern Labrador, Canada: Evidence for the oldest supracrustal rocks in the world. Precambrian Res., 278: 218-243.
• 30. WANLESS R.K., BRIDGWATER D. & COLLERSON K.D. 1979 - Zircon age measurements for Uivak-II gneisses from the Saglek area, Labrador. Can. J. Earth Sci., 16: 962-965.
• 31. YAVUZ F. 2001 - PYROX: A computer program for the IMA pyroxene classification and calculation scheme. Computers & Geosciences, 27: 97-107.

Uwagi

Opracowanie ze środków MNiSW w ramach umowy 812/P-DUN/2016 na działalność upowszechniającą naukę (zadania 2017).