The Journal of the Petrological Society of Korea (암석학회지)

The Petrological Society of Korea (한국암석학회)
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SHRIMP U-Pb Ages of the Namwon and Sunchang Granites

남원화강암과 순창화강암의 SHRIMP U-Pb 연령

  • Jo, Hui Je (Division of Earth Environmental System, Pukyong National University) ;
  • Park, Kye-Hun (Department of Earth Environmental Sciences, Pukyong National University) ;
  • Yi, Keewook (Division of Earth and Environmental Science, Korea Basic Science Institute)
  • 조희제 (부경대학교 일반대학원 지구환경시스템과학부 지구환경과학전공) ;
  • 박계헌 (부경대학교 환경해양대학 지구환경과학과) ;
  • 이기욱 (한국기초과학지원연구원 환경과학연구부)
  • Received : 2013.06.05
  • Accepted : 2013.06.26
  • Published : 2013.06.30
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Abstract

The Namwon and Sunchang granites are neighbouring plutons intruding the Yeongnam massif and the Okcheon metamorphic belt, respectively in the southwestern part of the Korean peninsula. In this study, SHRIMP zircon U-Pb ages are determined from these plutons. The results show that the emplacement age of the Namwon granite is $185.8{\pm}0.9(2{\sigma})$ Ma. We obtained $175.0{\pm}2.0(2{\sigma})$ Ma from the northern part and $179.8{\pm}0.9(2{\sigma})$ Ma from the central part of the Sunchang granite, yielding $177.4{\pm}1.3(2{\sigma})$ Ma as the average age of the pluton. Such age results confirm that the Honam shear zone, which cause marked deformation of the Sunchang granite, was active after ca. 175 Ma.

남원화강암과 순창화강암은 한반도의 남서부에서 각각 영남육괴와 옥천변성대를 관입하고 있는 인접암체이다. 이 연구에서는 가장 신뢰도가 높은 연령 분석방법으로 평가되는 SHRIMP를 이용하여 남원화강암과 순창화강암체의 저어콘 U-Pb 연대측정을 실시하였다. 그 결과 남원화강암체로부터 $185.8{\pm}0.9(2{\sigma})$ Ma의 정치연령을 구하였다. 한편 순창화강암체의 북부지역으로부터는 $175.0{\pm}2.0(2{\sigma})$ Ma, 그리고 중부지역으로부터는 $179.8{\pm}0.9(2{\sigma})$ Ma의 연령을 구하였으며, 순창화강암체의 분석자료 전체로부터는 $177.4{\pm}1.3(2{\sigma})$ Ma의 평균연령이 계산되었다. 이러한 결과는 순창화강암에 현저한 변형을 초래한 호남전단대의 활동이 약 175Ma 이후에도 일어났음을 확인해준다.

Keywords

References

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  1. Thermal and Uplift Histories of the Jurassic Granite Batholith in Southern Jeonju: Fission-track Thermochronological Analyses vol.49, pp.5, 2016, https://doi.org/10.9719/EEG.2016.49.5.389
  2. Gwangju Shear Zone : Is it the Tectonic Boundary between the Yeongnam Massif and Okcheon Metamorphic Belt? vol.23, pp.1, 2014, https://doi.org/10.7854/JPSK.2014.23.1.017