Journal of the Geological Society of Korea (지질학회지)

The Geological Society of Korea (대한지질학회)
권호 표지

Petrologic Studies on the Metamorphic Rocks in Wonju-P'yongch'ang Area

원주-평창 일대에 분포하는 변성암류에 대한 암석학적 연구

Lee, Sang-Man;Kim, Hyung-Shik;Hong, Seong-Tae;Park, Chan-Soo
이상만;김형식;홍성태;박찬수

  • Published : 19900200

⟨ Previous Next ⟩

Abstract

The Wonju-P'yongch'ang area occupies the southeast of the Kyonggi Massif, which is the Precambrian basement together with the Sobaeksan Massif. According to the metamorphic episode and geologic history, the metamorphic rocks of the area could be divided into five groups in stratigraphy, such as the Gneiss Complex, the Schist Group, Sinlim Limestone Formation of Precambrian and Ch'ondungsan Formation of unknown age and the Cambrian rocks. Ch'ondungsan Formation is correlated to Kyemyongsan Formation and overlies the Gneiss Complex unconformably. Also the Schist Group borders on the Gneiss Complex which is basement of this area with unconformity. The Schist Group borders on Ordovician carbonate rocks with a fault on the east side. Regional metamorphism is recognized at least three times, amphibolite facies, greenschist facies, greenschist to epidote-amphibolite facies series and prehnite-pumpellyite to greenschist facies series. The first episode of regional metamorphism occurred before the sedimentation of the Schist Group, while the last two were followed after the sedimentation. The third one was caused by the metamorphism of post-Cambrian. Temperature and pressure conditions of the first stage of the metamorphism are about $650-700^{\circ}C$ and 4-5 kb. Based on garnet-biotite geothermometry by Thompson (1976) and Ferry & Spear (1978), temperature condition of the second stage of metamorphism is about $500-580^{\circ}C$.

원주-평창 지역은 소백산육괴와 함께 선캠브리아기의 기저를 이루는 경기육괴의 남동부에 해당한다. 변성에피소드와 지사에 의하면 본역의 변성암은 층서적으로 선캠브러아기의 편마암복합체, 편암층군, 신림석회암층, 시대미상의 청등산층 그리고 캠브리아기의 암석들이다. 천등산층은 계명산층에 대비되며 부정합의 관계로 편마암복합체의 상부에 놓인다. 또한 편암층군도 기저의 편마암복합체와 부정합의 관계에 있다. 편암층군은 본역의 동측에서 오르도비스기의 회산염암류와 단층으로 접한다. 본역에는 최소한 3회의 광역변성작용이 인지되는데 이들은 각각 앰피볼라이트상, 녹색편암상 내지 녹렴석-앰피볼라이트상 계열, 프레나이트-품펠리아이트상 내지 녹색편암상 계열에 해당한다. 제1차 변성작용이 편암층군의 퇴적 이전에 일어난데 반해 제2차, 제3차 변성작용은 그 퇴적 이후에 일어났다. 제3차 변성작용은 캠브리아기 이후에 일어났다. 제1차 변성작용의 온도와 압력조건은 약 $600-700^{\circ}C$와 4-5kb이며 석류석-흑운모 지온계를 이용한 Thompson(1976)과 Ferry와 Spear(1978) 방법에 의하여 지온을 추정한 결과 제2차 변성작용의 온도는 약 $500-580^{\circ}C$이다.

Keywords

References

  1. Neues Jahrb. Mineral. Monat. v.7 An experimental reexamination of the upper stability of muscovite plus quartz Althaus, E.;Karotke, E.;Nitsch, K.H.;Winkler, H.G.F.
  2. PETCAL: A Basic Language Computer Program for Petrologic Calculations;Nevada Bureau of Mines and Geology, Report 28 Bingler, E.C.;Trexler, D.T.;Kemp, W.R.;Bonham, H.F. Jr.
  3. Geol. Soc. Am. Bull. v.83 Genesis of Garnet Hill Skarn, Calaveras County, California Brock, K.J.
  4. Contrib. Mineral. Petrol. v.48 Thermal stability and standard thermodynamic properties of 2Mmuscovite $KAl_2\;[AlSi_5O_{10}\;(OH)_2]$ Chatterjee, N.D.;Johnannes, W.
  5. Geological map of the Pyreongchang and Yeongweol, Sheet 6826-11, Scale 1 :50,000 Cheong, C.H.;Lee, D.Y.;Ryu, Y.S.;Kang, K.W.
  6. Am. Mineralogist v.58 The high-temperature stability of muscovite plus quartz Day, H.W.
  7. Geol. Soc. Am. Bulletin v.90 Mineral chemistry of some Franciscan blueschist facies metasedimentary rocks from the Diablo Range, California Moore, D.E.;Liou, J.G.
  8. Geological Society of American Memoir v.135 Ca-amphibolite paragenesis in the Shirataki district, Central Shikoku, Japan;Studies in Mineralogy and Precambrian geology Ernst, W.G.;Doe, B.R.(ed.);Smith, D.K.(ed.)
  9. Am. J. Sci. v.263 Application of a reaction-rate method to the breakdown equilibria of muscovite and muscovite plus quartz Evans, B.W.
  10. Am. Mineral. v.51 Phase relationships of chlorites in the system $MgO-Al_2O_3-SiO_2-H_2O$ Fawcett, J.J.;Yoder, H.S. Jr.
  11. Contri. Mineral. and petrol. v.66 Experimental calibration of the partitioning of Fe and Mg between biotite and garnet Ferry, J.M.;Spear, F.S.
  12. Am. J. Sci. v.264 Hydrothermal stability of clinozoisite plus quartz Holdway, M.J.
  13. Am. J. Sci. v.271 Stability of andalusite and the aluminum silicate phase diagram Holdaway, M.J.
  14. J. Petrol. v.9 Selected phase relationships in the system AI-Mn-Fe-Si-O-H -A model for garnet equilibria Hsu, L.C.
  15. Am. Jour. Sci. v.284 Polymetamorphic garnet zorning from southeastern vermont Karabinos, P.
  16. Am. Mineralogist v.58 Experimental determination of the muscovite + quartz Kerrick, D.M.
  17. Jour. Geol. Soc. Korea v.9 On Migmatites in Jeonju-Mogpo Area, Korea Kim, H.S.
  18. Jour. Geol. Soc. Korea v.12 Biotites from metapelites of the Ogcheon-Goesan District, Korea Kim, H.S.
  19. Geological Map of the Jecheon Sheet (1 :50,000) Kim, K.W.;Park, B.S.;Lee, H.K.
  20. Jour. Korean Inst. Mining Geol. v.4 Study on the Intrusion Epochs of Younger Granites and their Bearing to Orogenies in South Korea Kim, O.J.
  21. Jour. Korean Inst. Mining Geol. v.12 Petrological study on the Jecheon granite mass Kim, Y.J.
  22. Jour. Korean Inst. Mining Geol. v.18 Petrologic Study on the Basement and the Lowest Part of Ogcheon Zone and Igneous Intrusives in the Pyeong chang-Jucheon Area Lee, D.S.;Na, K.C.;Kim, Y.J.
  23. Jour. Korean Inst. Mining Geol. v.18 Igneous Activity in Ogcheon Geosynclinal Zone;Korea-with Special Reference to the Igneous Activity in its Northeastern Part Lee, D.S.;Kim, Y.J.
  24. Am. J. Sci. v.280-A Significance of FeMg Cordierite stability relations on temperature, pressure, and water pressure in cordierite granulites;The Earth's Crust, Its Nature and Physical Properties Lee, S.M.;Holdaway, M.J.;Heacock , J.G.(ed.)
  25. Geochim. Cosmochim. Acta v.27 Experimentelle Gesteinsmetamorphose-VII, Die Bildung von Talk aus Kieseligem Dolomit Metz, P.;Winkler, H.G.F.
  26. Contrib. Mineral. Petrol. v.18 On phase equilibria in metamorphosed siliceous dolomites Metz, P.;Trommsdorff, V.
  27. Jour. Geo. Soc. Korea v.14 Regional Metamorphism in the Gyeonggi Massif with Comparative Studies on the Yeoncheon and Ogcheon Matamorphic Belts (I) Na, K.C.
  28. Geological map of the Moggye Sheet (1 :50,000) Park, B.S.;Yeo, S.C.
  29. Contrib. Mineral. Petrol. v.27 Lower temperature stability limit of Mg-cordierite in the range 1-7 Kbar water pressure: a redetermination Seifert, F.;Schreyer, W.
  30. Jour. Soc. Mining Geologists, Japan v.33 K-Ar ages of the Jecheon Granite Complex and Related Molybdenite Deposits in South Korea Shibata, K.;Park, N.Y.;Ichimura, S.;Ishihara, S.
  31. Jour. Geo. Soc. Korea v.7 Geology of the Northwestern Part of Pyeongchang District, Gang weon-do, Korea Son, C.M.;Cheong, J.G.
  32. Jour. Petrol. v.3 The composition of garnets from pelitic schists in relation to the grade of regional metamorphism Sturt, B.A.
  33. Am. Jour. Sci. v.276 Mineral reactions in pelitic rocks: II. Calculation of some P-T-X (Fe-Mg) phase relations Thompson, A.B.
  34. Am. Mineral v.61 Garnet composition and zoning in the determination of temperature and pressure of metamorphism, central Messachusetts Tray, R.J.(et al.)
  35. Geological map of Sinlim Sheet, Sheet 6825-IV, Scale 1 :50,000 Won, C.K.;Yu, H.S.;Lee, Y.C.;Kim, J.J.
  36. Jour. Korean Inst. Mining Geol. v.19 Geology and Mineral resources of the Ogcheon Zone: Mineralization in the Pyeongchang-Jucheon Area, Kangwon-Do, Korea Yun, S.K.;So, C.S.;Kim, K.H.