Surface Microtopography of Pyrophyllite Crystals from Gussi Deposit, Korea

전남 구시광산에서 산출하는 엽납석 결정의 표면 미세형태

  • Mayumi Jige (Earth and Planetary Systems Science, Graduate School of Science, Hiroshima University) ;
  • Ryuji Kitagawa (Earth and Planetary Systems Science, Graduate School of Science, Hiroshima University) ;
  • Hwang, Jin-Yeon (Department of Geology, College of National Sciences, Pusan National University)
  • Published : 2004.06.01

Abstract

The surface microtopography of pyrophyllite collected from the Gussi deposit, Korea was observed by mean of transmission electron microscopy (TEM) with the gold decoration technique. As results, closed step patterns with malformed circular islands were characteristically observed on the (001) surface of pyrophyllite, contrasting with spiral step patterns common in illite and kaolinite. Gussi pyrophyllite was likely crystallized from hydrothermal solution of higher temperature and/or higher supersaturation than those of other clay minerals. Comparing with micro-topographies of pyrophyllite from the Shokozan and the Uku deposits, southwest Japan, growth mechanism of Gussi pyrophyllite is almost equivalent to those from the Shokozan and the Uku deposits.

한국 전남지역 구시광상에서 채취한 엽납석 시료에 대해 금 부착방법으로 투과전자현미경 (TEM)을 사용하여 결정표면의 미세 형태를 관찰하였다. 그 결과, 일라이트 및 고령석과 같은 점토광물에 일반적인 나선형 계단형태와 달리, 구시광상 엽납석의 (001)표면에는 다소 기형적인 원형의 섬 모양을 가진 폐쇄된 계단형태가 특징적으로 잘 관찰되었다. 이러한 관찰결과로 보아, 구시광상 엽납석은 다른 점토광물에 비하여 상대적으로 높은 온도와 혹은 더 과포화된 열수용액에서 성장한 것으로 사료된다. 구시광상 엽납석의 미세 형태는 서남 일본에 위치하는 쇼코잔광산과 우쿠광산의 엽납석과 매우 유사하므로, 엽납석의 결정성장 매카니즘도 이들과 거의 동일할 것으로 보인다.

Keywords

References

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