Economic and Environmental Geology (자원환경지질)

The Korean Society of Economic and Environmental Geology (대한자원환경지질학회)
권호 표지

Relation between Metamorphic P-T Conditions and Boron Concentrations of Metasedimentary Rocks and Biotite Granitic Gneisses from NE Yeongnam Massif around Samcheok Area, South Korea

영남 육괴 북동부 변성퇴적암과 흑운모 화강편마암의 변성 온도-압력 조건과 전압 붕소 함량사이의 상관관계

  • Cheong, Won-Seok (Korea Basic Science Institute, Geochronology Team) ;
  • Sun, Gwang-Min (Korea Atomic Energy Research Institute) ;
  • Na, Ki-Chang (Department of Earth & Environmental Science, College of natural Science, Chungbuk National University)
  • 정원석 (한국기초과학지원연구원 연대측정팀) ;
  • 선광민 (한국원자력연구원 원자로시스템기술개발본부) ;
  • 나기창 (충북대학교 자연과학대학 지구환경과학과)
  • Published : 2009.06.28
Download PDF
⟨ Previous Next ⟩

Abstract

This study is focused on the relationship between whole rock boron contents and metamorphic P-T conditions of metasedimentary rocks from northeastern Yeongnam massif around Samcheok area, Korea. Metamorphic P-T conditions of sillimanite and garnet zones based on the Ti-biotite geothermometer is 553-687$^{\circ}C$ and 582-722$^{\circ}C$ at 4-6 kbar, respectively. In the metasedimentary rocks, boron contents in whole rock decrease with increasing metamorphic grade, from sillimanite zone (9.60-189 ppm B) to garnet zone (2.63-15.97 ppm B), except one sample (90.9 ppm B) from garnet zone containing graphites. Boron depletion in garnet zone has relation with mode of tourmaline which are broken down with increasing metamorphic temperature. Boron contents are indirectly proportional to major and trace elements such as $Al_2O_3$, MgO, $Fe_2O_3$, $K_2O$, Li, Ba, Sc, Co, Cr, Rb and Cs that are abundant in tourmalines. In conclustion, tourmalines and graphite are modulator of boron contents in metasedimentary rocks. In the biotite granitic gneisses, boron contents (2.62-12.2 ppm B) are similar or lower than those of metasedimentary rocks and have no relation with metamorphic P-T conditions.

영남육괴의 북동부에 분포하는 변성퇴적암류의 전암 붕소를 분석했다. 연구지역의 변성퇴적암류는 광물 조합에 따라 규선석대와 석류석대로 나누어지며, Ti-흑운모 지온계를 이용한 4-6 kbar 사이의 변성온도는 각각 553-687$^{\circ}C$와 582-722$^{\circ}C$이다. 붕소의 전함량은 흑연이 다량 포함된 석류석대의 한개 시료(89.95 ppm B)를 제외하고 규선석대(9.60- 189.18 ppm B)에서 석류석대(2.63-15.97 ppm B)로 높은 온도를 지시하는 지역에서 상대적으로 적은 함량을 갖는다. 붕소와 양의 상관관계를 이루는 $Al_2O_3$, MgO, $Fe_2O_3$, $Fe_2O_3$, $K_2O$, Li, Ba, Sc, Co, Cr, Rb, Cs는 전기석을 구성하는 주원소로 전기석의 비율이 증가할수록 붕소의 함량이 증가한다는 것을 부분적으로 지시한다. 광물의 모드비와 붕소의 전함량 비교는 붕소를 조절하는 주된 광물이 전기석 및 흑연임을 지시한다. 흑운모 화강편마암의 전암 붕소 함량(2.62-12.2 ppm B)은 전반적으로 변성퇴적암보다 붕소함량이 낮거나 비슷하며 변성 압력-온도 조건과는 관련성이 없다.

Keywords

References

  1. Anovitz, L.M. and Grew, E.S. (1996) Mineraolgy, petrology and geochemistry of boron: an introduction. In Grew, E.S. and Anovitz, L.M.(ed.) Boron-Mineralogy, Petrology and Geochemistry, Reviews in Mineralogy. v.33, Mineralogical society of America, p.1-40
  2. Byun, S.H., Sun, G.M. and Choi, H.D., (2002) Development of a prompt gamma activation analysis facility using diffracted polychromatic neutron beam. Nuclear Instruments and Methods in Physics Research A. v.487, p.521-529 https://doi.org/10.1016/S0168-9002(02)00394-7
  3. Byun, S.H., Sun, G.M. and Choi, H.D. (2004) Prompt gamma activation analysis of boron in reference materials using diffracted polychromatic neutron beam. Nuclear Instruments and Methods in Physics Research B. v.213, p.535-539 https://doi.org/10.1016/S0168-583X(03)01626-4
  4. Cheong, W.S., Cheong, S.W. and Na, K.C. (2006) Petrocheomistry and geologic structure of Icheong granitic gneiss aroun Samcheonk area, Korea. Journal of Petrology Society of Korea, v.15, p.25-38
  5. Cheong, W.S. and Na, K.C. (2007) Tourmaline reaction and metamorphism in the metasedimentary rocks of northeastern Yeongnam massif. Proceedings of the Annual Joint Conference, Mineralogical and Petrological Society of Korea, p.47-49
  6. Cheong, W.S. and Na, K.C. (2008) Origin and evolution of leucogranite of NE Yeongnam massif from Samcheok area, Korea. Journal of Petrology Society of Korea, v.17, p.16-35
  7. Failey, M.P., Anderson, D.L., Zoller, W.H., Gordon, G.E. and Lindstrom, R.M. (1979) Neutron-capture prompt gamma-ray activation analysis for multielement determination in complex samples. Analytical Chemistry, v.51, p.2209-2221 https://doi.org/10.1021/ac50049a035
  8. Henry, D.J. and Dutrow, B.L. (1996) Metamorphic tourmaline and its petrologic applications. In Boron- Mineralogy, Petrology and Geochemistry, In Grew, E.S. and Anovitz, L.M.(ed.) Boron-Mineralogy, Petrology and Geochemistry, Reviews in Mineralogy. v.33, Mineralogical society of America, p.503-557
  9. Henry, D.J., Guidotti, C.V. and Thomson, J.A. (2005) The Ti-saturation surface for low-to medium-pressure metapelitic biotites: implications for geothermometry and Ti-substitution mechanism. American Mineralogist, v.90, p.316-328 https://doi.org/10.2138/am.2005.1498
  10. Kawakami, T. (2001) Tourmaline Breakdown in the migmatite zone of the Ryoke metamorphic belt, SW Japan. Journal of Metamorphic Geology, v.19, p.61-75 https://doi.org/10.1046/j.0263-4929.2000.00298.x
  11. Kawakami, T. (2004) Tourmaline and boron as indicators of the presence, segregation and extraction of melt in pelitic migmatites: examples from the Ryoke metamorphic belt, SW Japan. Transactions of the Royal Society of Edinburgh : Earth Sciences, v.95, p.111-123 https://doi.org/10.1017/S0263593304000124
  12. Kawakami, T. and Ikeda, T. (2003) Boron in metapelites controlled by the breakdown of tourmaline and retrograde formation of borosilicates in the Yanai area, Ryoke metamorphic belt, SW Japan. Contributions to Mineralogy and Petrology, v.145, p.131-150 https://doi.org/10.1007/s00410-002-0437-7
  13. Kretz, R. (1983) Symbols for rock forming minerals. American Mineralogist, v.68, p.277-279
  14. Lee, S.M., Kim, H.S. and Oh, I.S. (1986) Metamorphic petrology of Precambrian gneisses in Samcheok- Jukbyeon area. Journal of Geological Society of Korea, v.22, p.257-277
  15. Lee, S.G., Kim, K.H., Song, Y.S., Kim, N.H. and Park, K.H. (2007) Geocheomical implication of rare earth element tetrad effect from a leucocratic granite gneiss in the Imweon area, Gangwon province, Korea. Journal of Petrology Society of Korea, v.16, p.27-37
  16. London, D. and Morgan, G.B. VI, (1996) Boron in granitic rocks and their contact aureoles. In Boron-Mineralogy, Petrology and Geochemistry, In Grew, E.S. and Anovitz, L.M.(ed.) Boron-Mineralogy, Petrology and Geochemistry, Reviews in Mineralogy. v.33, Mineralogical society of America, p.299-330
  17. Mason, B. and Moore, C.B. (1982) Principles of geochemistry. 4th(ed.), John Wiley & Sons, 344p
  18. Moran, A.E., Sisson V.B. and Leeman W.P. (1992) Boron depletion during progressive metamorphism: implications for subduction processes. Earth and Planetary Science Letters, v.111, p.331-349 https://doi.org/10.1016/0012-821X(92)90188-2
  19. Morgan, G.B. VI and London, D. (1989) Experimental reactions of amphibolite with boron-bearing aqueous fluids at 200 MPa: implications for tourmaline stability and partial melting in mafic rocks. Contributions to Mineralogy and Petrology, v.102, p.281–297 https://doi.org/10.1007/BF00373721
  20. Nakano, T. and Nakamura, E. (2001) Boron isotope geochemistry of metasedimentary rocks and tourmalines in a subduction zone metamorphic suit. Physics of the Earth and Planetary Interiors, v.127, p.233-252 https://doi.org/10.1016/S0031-9201(01)00230-8
  21. Patino Douce, A.E. (1993) Titanium substitution in biotite: an empirical model with applications to thermometry, $O_2$ and $H_2O$ barometries, and consequences form biotite stability. Chemical Geology, v.108, p.133-162 https://doi.org/10.1016/0009-2541(93)90321-9
  22. Robert, J.L. (1976) Titanium solubility in synthetic phlogopite solid solutions. Chemical Geology, v.17, p.213-227 https://doi.org/10.1016/0009-2541(76)90036-X
  23. Wilke, M., Nabelek, P.I. and Glascock, M.D. (2002) B and Li in Proterozoic metapelites from the Black Hills, U.S.A.: Implications for the origin of leucogranitic magmas. American Mineralogist, v.87, p.491-500 https://doi.org/10.2138/am-2002-0412
  24. Xu, L. and Rao, Z. (1986) Determination of boron in soils by sequential scanning ICP-AES using side line indexing method. Fresenius' Journal of Analytical Chemistry, v.325, p.534-538 https://doi.org/10.1007/BF00635682