Economic and Environmental Geology (자원환경지질)

The Korean Society of Economic and Environmental Geology (대한자원환경지질학회)
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Mineralogy and Geochemistry of Ultramafic Rocks from the Singok Area, Western Part of Chungnam

충남 서부 신곡 지역에 분포하는 초염기성암의 광물조성 및 지구화학

  • 송석환 (중부대학교 환경공학과) ;
  • 송윤섭 (고려대학교 지구환경공학과)
  • Published : 2001.08.01
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Abstract

In the Singok area, western part of Chungcheongnam-Do, two ultramafic ma~ses, Singok mass and Kaewol mass, occur as isolated lenticular bodies in the Precambrian Kyeonggi gneiss complex. The masses extend for several hundred meter to NNE direction, parallel to the main fault line of this area. The rocks are dunite and harzburgite, but partially and absolutely serpentinized. They dominantly show porphyroclastic and recrystallized textures with equigranular-mosaic and protogranular textures. In spite of differences among the alteration and metamorphism, the ultramafic masses are characterized by varying amounts of high fosteritic olivine ($Fo_{0.88-0.93}$), magnesian pyroxene ($En_{0.93-0.97}$), and tremolitic to tschermakitic hornblende with minor spinel, serpentine, chlorite, calcite, magnetite, phlogopite and talc. It is compared with adjacent gneiss complex containing amphibole, biotite, plagioclase, alkali-feldspar and quartz. Geochemically, these rocks show high magnesium number (Mg>90.38), and transitional element (Ni=595-2480, Cr==IOlO-4400, Co=36-120 ppm), low alkali element ($Na_{2}O$<0.3, $K_{2}O$<0.11, $Al_{2}O_3$<2.95 wt%) and depleted incompatible element contents, which is compared with adjacent rocks (Mg < 83.69, $Na_{2}O$=1.02-3.42 wt%, $K_{2}O$=O.67-5.65 wt%, $Al_{2}O_3$=9.15-16.86 wt%, Ni < 435 ppm, Cr < 1440 ppm, Co<59 ppm, enriched incompatible element contents). Overall characteristics of ultramafic rocks from the Singok and Kaewol masses are similar to the those of adjacent ultramafic bodies in Chungnam with worldwide orogenic related Alpine type ultramalic rocks. Calculated geothermometries suggest that the ultramafic rocks have experienced metamorphism in the condition ranging from the greenschist facies to granulite facies.

충남 서부 신곡 및 계월 두 초염기성 암체가 선캠브리아기 경기 편마암 복합체내에서 격리된 안구상 암체로서 산출되고 있다. 이 암체들은 이 지역의 우세한 구조선 반향인 NINE 방향과 평행하게 수백 m 신장되어 분포한다. 이 암석들은 완전히 또는 부분적으로 사문암화 및 활석화 되었고 잔쇄 반상조직이 두드러지며 등립질-모자이크조직 및 원생입상조직을 보이기도 한다. 광물 조성상 듀나이트 또는 하즈버자이트로 변질 및 변성정도에 따른 차이를 보이기도 하지만 높은 포스테라이트 조성의 감람석($Fo_{0.88-0.93}$), 엔스테타이트 조성의 사방휘석($En_{0.93-0.97}$), 트래모라이트질에서 체마카이트질의 각섬석 및 투각섬석을 주로 포함하고 첨정석, 사문석, 녹리석, 방해석, 자철석, 금운모, 활석등을 포함하기도 한다. 이런 특징들은 주변의 각섬석, 흑운모, 사장석, 알칼리 장석, 석영을 포함하는 편마암 복합체와 뚜렸이 구분이 된다. 지화학적으로 이 암석들은 높은 마그네슘비(Mg>90.38) 및 전이 원소(Ni=595-2480, Cr=1010-4400, Co=36-120 ppm) 함량과 낮은 알칼리 원소($Na_{2}O$<0.3, $K_{2}O$<0.11, $Al_{2}O_3$<2.95 wt%) 함량 및 결핍된 비호정성 원소들의 빈도가 특징적이다. 이런 특징들은 주변암이 보이는 것들(Mg<83.69, $Na_{2}O$ = 1.02-3.42 wt%, $K_{2}O$=0.67-5.65 wt%, $Al_{2}O_3$ = 9.15-16.86 wt%, Ni< 435 ppm, Cr < 1440 ppm, Co < 59 ppm, 부화된 비호정 성원소함량)과 차이를 보인다. 이 암체들의 암석학적, 지화학적, 광물학적 결과들은 충남 인접지역 및 전세계의 지구조적으로 노출된 알파인형의 초염기성암과 유사하다. 계산된 지질온도는 이 암석이 상부녹색편암상에서 백립암상에 해당되는 온도범위에서 변성작용을 받았음을 암시한다.

Keywords

References

  1. 한국지질도 1:50,000 광정지질 도폭 강필종;임주환
  2. 광산지질 v.26 울산 철광산지역 사문암의 사문암화작용에 관한 연구 김규환;박재경;양종만;Hiroshi Satake
  3. 지질학회지 v.26 울산 철광산의 탄삼염과 사문암의 성인 김규환;박재경;양종만;Yoshida Naohhiro
  4. 한국지질도 1:50,000 공주 지질 도폭 김서운;유환수;우영균
  5. 한국지질도 1:50,000 대흥지질도폭 및 설명서 엄상호;이민성
  6. 광산지질 v.24 충남 예산지구 활석광산의 성인에 대한 연구 우영균;최석원;박기화
  7. 자연환경지질 v.27 초염기성암 기원의 평안 및 대흥활석광상의 성인과 광물화학 윤상필;문희수;송윤구
  8. 암석학회지 v.3 대흥 활석 광상 주변의 편마암류의 지화학적 특징과 공존광물의 화학적 평형 이상헌;최기주
  9. 한국지질도 1:50,000 홍성지질도폭 및 설명서 이종혁;김성수
  10. 광산지질 v.10 사문석의 활석화과정에 관한 연구 지정만;김규봉
  11. 충남 홍성 및 광첨지역 초염기성 암체의 광물 조성 및 암석지구화학 최선규;송석환;최성호
  12. 지질학회지 v.26 울산사문암체의 광물학적, 지구화학적 연구 최수용;황진연;김정진;이윤종
  13. 광산지질 v.26 안동지역 사문암 광산의 구성광물 및 성인에 관한 연구 황진연;김정진;옥수석
  14. Lithos v.21 Chrome spinels from the Oura layered igneous complex, central Japan Agata, T.
  15. Chemical Geol. v.134 Geochemistry of garnet peridotite massifs from lower Austria and the composition of deep lithosphere beneath a Palaeozoic convergent plate margin Becker, H.
  16. Amer. Miner. v.54 Chemical composition of altered chlomites from the Stillwater Complex, Montana Beeson, M.H.;Jackson, E.D.
  17. Tectonophy. v.149 Geochmistry and petrogenesis of the Lanzo peridotite body, western Alps. Bodinier, J.L.
  18. Geol. soc. Amer. Bull. v.93 Pyroxene orientation within the mantle Christensen, N.I.;Lundquist, S.M.
  19. Minerals and Rocks v.12 Ophiolites-ancient oceanic lithosphere? Coleman, R.G.;Wyllie, P.J.(ed.)
  20. Tectonophy. v.7 Origin of ultramafic rocks, their tectonic setting and history: A contribution to the discussion of the paper Den Tex, E.
  21. Contrib. Miner. Petrol. v.86 Chromian spinel as a petrogenetic indicator in abyssal and Alpine-type Peridotites and Spartially associated lavas. Dick, H.J.B.;Bullen, T.
  22. J. Petrol. v.86 Petrogenesis of ultramafic metamorphic rocks from 3800 Ma isua supracrustal belt, western Greenland Dymek, R.F.;Brothers, S.C.;Schiffries, C.M.
  23. Chemical Geol. v.122 Geochemistry of chromitites and host rocks from the Pindos ophiolite complex, northwestern Greece Economou-Eliopoulos, M.;Vacondios, I.
  24. Contrib. Miner. Petrol. v.69 Spinel-olivine geothermometry in peridotites from ultramafic complexes Fabries, J.
  25. Geochim. Cosmochim. Acta. v.33 Rare earth aboundances in a high-tem-perature peridotite intrusion Frey, F.A.
  26. Tectonophy. v.147 Petrology and texture of the ultramafic rocks of the Xigaze ophiolite(Tibet): Constrains for mantle structure beneath slow-spreading ridges Girardeau, j.;Mercier, J.C.C.
  27. Amer. Miner. v.53 Altered chrome ores from the Coolac serpentinite belt, New South Wales, Australia Golding, H.G.;Bayliss, P.
  28. Geochim. Cosmochim. Acta. v.52 Mantle metasomatism beneath western Victoria, Australia: Ⅱ. Isotopic geochemistry of Cr-diopside lherzolites and Al-augite pyroxenite Griffin, W.L.;O'Reilly S.Y.;Stable, A.
  29. J. Petrol. v.25 Ultramafic xenoliths from Bullenmerri and Gnotuk Maars, Victoria, Australia: petrology of sub-continental crustmantle transition Griffin, W.L.;Wass, S.Y.;Hollis, J.D.
  30. Chemical Geol. v.77 Mineral chemistry of ultramafic tectonites and ultramafic to gabbroic cumulates from the major oceanic basins and northern Apennine ophiolites (Italy): A comparison Herbert, R.;Serri, G.;Herkinian, R.
  31. Crust of The Earth. Geol. Soci. Amer. Spec. Pap. v.62 Serpentines, orogeny and epiogeny Hess, H.H.;Polervaart, A.(ed.)
  32. Miner. Mag. v.30 New review of chlorites Hey. M.H.
  33. The Eastern Australian lithosphere. Geol. Soc. Aust. Spec. Pub. v.17 The Petrological basis for the interpretation of seismological models for continental lithosphere Jackson, I.;Drummond, B.J.(ed.)
  34. Tectonphy. v.101 Laboratory wave velocity measurements on lower crustal xenoliths from Calcutteroo, South Australia Jackson, I.;Arculus, R.J.
  35. Tectonphy. v.173 Measured and calculated elastic wave velocities for xenoliths from the lower crust and upper mantle Jackson, I.;Rudnick, R.L.;O'Reilly S.Y.;Bezant, C.
  36. Contrib. Miner. Petrol. v.121 Contrasting PT conditions recorded in ultramafic high pressure rocks from the Variscan Schwarzland (F.R.G) Kalt, A.;Altherr, R.;Hanel, M.
  37. Amer. J. Sci. v.284 Chromite from the Blue Ridge province of North Calorina Lipin, B.R.
  38. Earth Planet. Sci. Lett. v.101 Constrains on the composition of the continental lithospheric mantle McDonough, W.F.
  39. Geochim. Cosmochim. Acta. v.40 Rare earth geochemistry of fused ophiolitic and alpine lherzolites-l. Othris, Lanzo and Troodos Mezies, M.
  40. Tectonophy. v.190 Emplacement of deep crustal and mental rocks on the West Median valley, Wall of the mark area (MAR), 23°N Mevel, C.;Canat, M.;Gente, P.;Marion, E.;Auzende, J.M.;Karson, J.A.
  41. Ultramafic Rocks of the Appalachian Piedmont (ed.) Geol. Soc. Amer. Spec. Pub. v.231 Mittwede, S.K.;Stoddard, E.F.
  42. Nature v.250 Ophiolites and oceanic crust Moores, E.M.;Jackson, E.D.
  43. Studies in Earth and Space science. Geol. Soc. Amer. Memor. v.132 Types of alpine ultramafic rocks and their implication for fossil plate interactions Moores, E.M.;MacGregor, I.E.;Shagam, R.(et al.)(ed.)
  44. Structures of ophiolites and dynamics of oceanic lithophere Nicolas, A.
  45. Geochim. Cosmochim. Acta. v.52 Mantle metasomatism beneath western Victoria, Australia: Ⅰ. Metasomatic processes in Cr-diopside iherzolites O'Reilly, S.Y.;Griffin, W.L.
  46. J. Petrol. v.35 Melting and melt segregation in the mantle wedge above a subduction zone: Evidence from the chromite-bearing peridotites of the miyamori ophiolite complex, Northeastern, Japan Ozawa, K.
  47. Canadian Miner. v.22 Metamorphism of the ultramafic rocks of the Thompson mine, Thompson nickel belt, Northern Manitovia Paktung, A.D.
  48. J. Geophy. Res. v.86 Rare-Earth Element Geochemistry of the Samail Ophiolite near Ibra, Oman Pallister, J.S.;knights, R.J.
  49. Contrib.Miner. Petrol. v.95 Serpentinization and infiltration metasomatism in the Trinity Periotite, Klamath province, northern California: implications for subduction zones Peacock, S.M.
  50. J. Petrol. v.36 Petrology, mineral and isotope geochemistry of the external Liguride peridotites (Northern Apennines, Italy)ENG Rampone, E.M.;Hofmann A.W.;piccardo, G.B.;Vanuggi. R.;Bottazzi, P.;Ottolini, L.
  51. Metamorphic petrology Raymond, L.A.
  52. Contrib. Miner. Petrol. v.127 Garnet-bearing ultramafic rocks from the Erzgebirge, and their relation to other settings in the Bohemian Massif Schmadicke, E.;Evans, B.W.
  53. Econ. Environ. Geol. v.30 Genetic implications of ultramafic rocks from the Bibong area in the Kyeonggi gneiss complex Song, S.H.;Choi, S.G.;Woo, J.G.
  54. J. Korean Inst. Mining Geol. v.24 Supergene chloritization and vermiculitization in hornblende gneiss, the Cheongyang area Song, Y.;Moon, H.S.
  55. Amer. J. Sci. v.290 The Ropes Creek assemblage: Petrology, geochemistry and tectonic setting of an ophiolitic thrust sheet in the southern Appalachians Spell, T.L.;Norrell, G.T.
  56. Earth Planet. Sci. Lett. v.45 Bay of Islands ophiolite suite, Newfoundland: petrologic and geochemical characteristics with emphasis on rare earth element geochemistry Suen, C.J.;Frey, F.A.;Malpas, J
  57. Magmatism in the Ocean Basins. Geol. Soc. Spec. Publ. v.42 Chemical and isotopic systematics of oceanic basalts: implications for mantle composition and processes Sun, S.S.;McDonough, W.F.;Saunders, A.D.(ed.);Norry, M.J.(ed.)
  58. Contrib. Miner. Petrol. v.132 High pressure breakdown of antigorite to spinifex-textured olivine and orthopyroxene, SE spain Trommsdorff, V.;Sanchez-Vizcaino, V.L.;Gomez- Pugnaire, M.T.;Muntener, O.
  59. Chemical Geol. v.129 interactions between melt and upper-mantlt peridotites in the North Arm Mountain Massif, bay of Island ophiolite, Newfoundland, Canada: Implictions for the genesis of bonintic and related magmas Varfalvy, V.;Herbert, R.;Bedard, J.H.
  60. Korea. Econ. Environ. Geol. v.27 Preliminary study on ultramafic rocks from the Chungnam Province Wee, S.M.;Choi, S.G.;So, C.G.
  61. Amer. Miner. v.55 Chemical differences among the serpentine "Polymorphys" : a discussion Whittaker, E.J.W.;Wicks F.J.