보배광산의 열수변질 점토광상의 K2O - Al2O3 - SiO2 - H2O 계에서의 일라이트 형성

추창오,김수진 ( Chang Oh Choo,Soo Jin Kim ) 한국광물학회 1992 광물과 암석 (J.Miner.Soc.Korea) Vol.5 No.1

보배광산에서 산출하는 열수변질 기원 녹염석의 분광학적 특성 : 적외선 및 뫼스바우어 연구

추창오,김수진 ( Chang Oh Choo,Soo Jin Kim ) 한국광물학회 1996 광물과 암석 (J.Miner.Soc.Korea) Vol.9 No.2

일라이트 , 할로이사이트에 대한 중금속 원소의 흡착특성

추창오,김수진,정찬호,김천수 ( Chang Oh Choo,Soo Jin Kim,Chan Ho Jeong,Chun Soo Kim ) 한국광물학회 1998 광물과 암석 (J.Miner.Soc.Korea) Vol.11 No.1

Characteristics of crystal from and habit of dickite from Deogbong mine, Kimhae

추창오(Chang Oh Choo) 대한지질학회 2001 지질학회지 Vol.37 No.4

Characteristics of crystal form and habit of hydrothermal dickite from the Deogbong clay mine, Kimhae-gun, Kyungsangnam-do, were studied to interpret formation conditions of dickite. The Hinckley index (HI) of dickite varies from 0.56 to 1.2, which is related to the crystal form having different sizes. Dickite varies in its morphology and crystallinity depending on paragenesis and locality. Stacks of crystal plates of dickite produce vermiform or horse’s hoof shape with an U-form. Vermiform is composed of numerous dickite crystals stacked with several hundred microns in length. The occurrence of vermiform stacks suggests that dickite formed under undersaturated solution. Euhedral, well-crystallized dickite indicates that it might have formed by the direct precipitation from hydrothermal solution at acidic conditions.

부산 금정산 일대 지하수공내 공막힘 물질의 특징과 형성원인

추창오 ( Chang Oh Choo ),함세영 ( Se Yeong Hamm ),이정환 ( Jeong Hwan Lee ),이층모 ( Chung Mo Lee ),추연우 ( Youn Woo Choo ),한석종 ( Suk Jong Han ),김무진 ( Moo Jin Kim ),조회남 ( Heuy Nam Cho ) 대한지질공학회 2012 지질공학 Vol.22 No.1

The physical, chemical, and biological properties of clogging materials formed within groundwater wells in the Mt. Geumjeong area, Busan, Korea, were characterized. The particle size distribution (PSD) of clogging materials was measured by a laser analyzer. XRD, SEM, and TEM analyses were performed to obtain mineralogical information on the clogging materials, with an emphasis on identifying and characterizing the mineral species. In most cases, PSI) data exhibited an near log-normal distribution; however, variations in frequency distribution were found in some intervals (bi-or trimodal distributions), raising the possibility that particles originated from several sources or were formed at different times. XRD data revealed that the clogging materials were mainly amorphous ironhy-droxides such as goethite, ferrihydrite, and lapidocrocite, with lesser amounts of Fe, Mn, and Zn metals and silicates such as quartz, feldspar, micas, and smectite. Reddish brown material was amorphous hydrous ferriciron (HFO), and dark red and dark black materials were Fe, Mn-hydroxides. Greyish white and pale brown materials consisted of silicates. SEM observations indicated that the clogging materials were mainly HFO associated with iron bacteria such as Gallionella and Leptothrix, with small amounts of rock fragments. In TEM analysis, disseminated iron particles were commonly observed in the cell and sheath of iron bacteria, indicating that iron was precipitated in close association with the metabolism of bacterial activity. Rock-forming minerals such as quartz, feldspar, and micas were primarily derived from soils or granite aquifers, which are widely distributed in the study area. The results indicate the importance of elucidating the formation mechanisms of clogging materials to ensure sustainable well capacity.

경북지역 주요 약수의 지화학과 침전물의 광물학적 특성

추창오 ( Chang Oh Choo ),이진국 ( Jin Kook Lee ) 한국광물학회 2009 광물과 암석 (J.Miner.Soc.Korea) Vol.22 No.2

경북 청도군 유천화강암 내 제올라이트 광물군 스텔러라이트의 산출과 광물학적 특징

추창오 ( Chang Oh Choo ),이진국 ( Jin Kook Lee ),조현구 ( Hyen Goo Cho ) 한국광물학회 2008 광물과 암석 (J.Miner.Soc.Korea) Vol.21 No.4

Because stellerite, belonging to the zeolite group, is much less common mineral than any other minerals in Korea, little mineralogical study has been done so far. Stellerite occurs on open surfaces of fractured zones in the Yucheon Granite associated with flowery tourmaline, Chongdo, Gyeongsangbuk-do. Stellerite with 3~4mm length and 1~2mm width is characterized by an equigranular and euhedral form. Flat and elongated columnar crystals show well developed (010) face. Stellerite shows an intensive alteration process, possibly due to weathering or devitrification, as evidenced by microtextural analysis of Scanning Electron Microscope (SEM). Water loss occurs at 161℃ while dehydroxylation occurs at 467℃ causing decomposition of the structure afterward. From its textural observation, it is concluded that stellerite formed rapidly at small undercooling, precipitated from residual melt during the late stage with relatively constant chemistry.

2004년 가창댐 탁수의 원인과 부유물질의 환경지질학적 특징

추창오 ( Chang Oh Choo ),고은영 ( Eun Young Koh ),오수진 ( Soo Jin Oh ),이성우 ( Seong Woo Lee ),김병기 ( Byoung Ki Kim ),이지은 ( Ji Eun Lee ),김영규 ( Yeong Kyoo Kim ) 한국광물학회 2006 광물과 암석 (J.Miner.Soc.Korea) Vol.19 No.1

화학적 풍화에 의한 결정질 암석내의 미세조직 발달특징과 암반공학적 의미

추창오 ( Chang Oh Choo ),정교철 ( Gyo Cheol Jeong ) 대한지질공학회 2011 지질공학 Vol.21 No.4

Weathering can reduce rock strength and eventually affect the structural stability of a rock mass, which is important in the field of engineering geology. Several methods have been developed lo evaluate the degree of weathering, including the chemical weathering index. In this study, we analyzed the weathering degree and characteristics of microtextures and pores in crystalline tucks (gneiss and granites) based on petrographic observations, the chemical weathering index, mineralogy by XRD, microtextural analysis by SEM/EDS, measurements of pore size and surface area by the BET method, and microporosity by X-ray CT. The formation of secondary minerals and micrutexture in gneiss and granitic rocks are assumed to be affected by complex processes such as dissolution, precipitation, and fracturing. Hence, it is clear that some chemical weathering indices that are based solely on whole-rock chemistry (e.g., C1A and CWI) are unable to provide reliable assessments of the degree of weathering. Great care is needed to evaluate the degree of chemical weathering, including an understanding of the mineralogy and microtexture of the rock mass, as well as the characteristics of micropores.

달성폐광산 산성광산배수의 발달특징과 슈베르트마나이트의 역할

추창오 ( Chang Oh Choo ),정교철 ( Gyo Cheol Jeong ),이진국 ( Jin Kook Lee ) 대한지질공학회 2007 지질공학 Vol.17 No.2

The Dalseong acid mine drainage were studied focused on the characters of schwertmannite that controls geochemistry of the stream. Besides chemical analysis of stream water, particle size analysis, XRD, SEM, and TEM were performed on precipitates of streams and on wasted metalliferous ores. The AMD discharged from the abandoned mine reveals a decrease of pH and EC downward stream. Euhedral sulfur occurs as equigranular aggregates on the altered pyrite while fine acicula goethite coalesces to form cross, star, or starfish-like shapes. Water chemistry plotted on the Eh-pH diagram shows that schwertmannite and ferrihydrite are stable phases. Reddish brown precipitates consist of mostly schwertmannite with less goethite, whereas yellowish brown precipitates are composed of geothite with less schwertmannite. The particle size of precipitates ranges d(0.1) 0.861 μm~3.769 μm, d(0.5) 3.984 μm~15.255 μm, and d(0.9) 9.875 μm~56.726 μm. Schwertmannite is characterized by equigranular spheric form. Pincushion or spicule with 100nm width and 200~300 nm length form on schwertmannite sphere with radial growth patterns. It is highly probable that reddish or yellowish brown precipitates formed in many AMDs may contain schwertmannite. Because it can serve as sink for removing heavy elements by adsorption in AMD system, there is a need to correctly identify schwertmannite in precipitates and to characterize its phase stability.